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Experimental and human studies describe the adverse effect of iron or vitamin B6 deficiencies on polyunsaturated fatty acid metabolism. Iron is present in end proteins of the δ6-desaturase enzyme complex, and vitamin B6 deficiency can affect the transmethylation reaction of proteins. Plasma polyunsaturated fatty acid content was estimated in apparently healthy subjects of the general population with no consumption of fish and low vitamin B6 serum levels (<3 μg/l; n = 21) or with low iron serum levels (men: <12 μmol/l; women: <10 μmol/l; n = 16) and compared to a control group (n = 22) with normal vitamin B6 and iron serum levels (in reference range). The activities of the δ6-desaturase enzyme complex were calculated as product/precursor (conversion indices). In groups of subjects with low vitamin B6 and low iron levels, δ6-desaturase activity together with δ5-desaturase activity (conversion of α-linolenic/18:3,n–3/ into eicosapentaenoic acid/20:5,n–3/) as well as the conversion index of docosahexaenoic acid formation (22:6,n–3) from 22:5,n–3 (second δ6-desaturase activity) were significantly reduced. The inhibition effect on fatty acid synthesis was more pronounced in subjects with low iron levels than in those with low vitamin B6 levels. The conversion indices correlated significantly positively with vitamin B6 or iron levels. Copyright © 2004 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Folic acid (vitamin B9) rich sources are leafy green vegetables, legumes, whole grains, egg yolk, liver, and citrus fruit. In winter and early spring, there could be insufficient supply of vegetables and fruit and thus lower intake of folic acid and possible deficient folic acid blood concentrations. The aim of the study was to assess serum vitamin B9 concentrations depending on the season (the last third of winter - March, the last third of spring - May/June and the beginning of autumn - September) and different nutritional habits (apparently healthy adults non-smoking, non-obese 366 subjects; 204 persons of general population on traditional mixed diet; and 162 long-term lacto-ovo vegetarians). In general population group, the mean concentration of folate in March was low (narrowly above lower reference limit) with high incidence of deficient values - 31.5%. In May/ June vs. March was folate concentration significantly higher with deficient values in 13.2% of individuals. The highest serum values were observed in September with 11.1% of deficient values. In vegetarian vs. non-vegetarian group, significantly higher folate concentrations were found in each season with no deficient values. Folate and vitamin B12 are the regulators of homocysteinemia; plant food lacks of vitamin B12. The deficient folate serum values in March caused the mild hyperhomocysteinemia in 12.3% of individuals vs. only 5.9% and 4.8% of subjects in groups investigated in May/June and September. In spite of high folate concentrations in all investigations and no deficient value, 19.6-22.8% of vegetarians suffer from mild hyperhomocysteinemia as a consequence of deficient vitamin B12 concentrations in one quarter of subjects. As far as the general population is concerned, our findings suggest that winter and early spring are critical seasons in regards to optimal serum folate concentrations.

Background: A long-term vegetarian diet is generally poor in vitamin B group. The lack of vitamin B(12) together with vitamin B(6) and folate deficiency is closely related to homocysteine metabolism. Hyperhomocysteinemia was found to be associated with increased bone turnover markers and increased fracture risk. Thus, hyperhomocysteinemia, vitamin B(12) and folate deficiency may be regarded as novel risk factors for micronutrient deficiency-related osteoporosis., Aim of the Study: To assess the possible impact of a vegetarian diet on bone mineral density in cohort of Slovak vegetarian women., Methods: Fasting serum glucose, albumin, calcium, phosphorous and creatinine as well as bone markers, serum vitamin B(12), folate and plasma levels of total homocysteine were assessed in two nutritional groups (vegetarians vs. nonvegetarians) of apparently healthy women (age range 20-70 years). Bone mineral density of the femoral neck, trochanter, total femur and lumbar spine was measured in all subjects., Results: Vegetarians had a significantly lower weight (p < 0.05), higher PTH (p < 0.01) and homocysteine (p < 0.001). Vitamin B(12) was significantly higher in nonvegetarians (p < 0.001). No differences were observed in folate levels. Univariate analysis showed significant association between homocysteine and B(12) (p < 0.01), folate (p < 0.001), creatinine (p < 0.001), total proteins (p < 0.049), age (p < 0.001) and vegetarian food intake (p < 0.001). Vegetarians had a significantly lower TrFBMD (p < 0.05) and ToFBMD (p < 0.05). Age and CTx were significant predictors in all sites of measured BMD and PTH. A strong correlation between homocysteine and FNBMD (r = -0.2009, p < 0.002), TrFBMD (r = -0.1810, p < 0.004) and ToFBMD (r = -0.2225, p < 0.001) was found in all subjects., Conclusion: Homocysteine is one of the predictors of bone mineral density, and hyperhomocysteinemia is associated with lower bone mineral density. In healthy adults, homocysteine levels are dependent on age as well as on nutritional habits. Thus, elderly women on a vegetarian diet seem to be at higher risk of osteoporosis development than nonvegetarian women.

A vegetarian diet results in higher intake of vitamins and micronutrients, which - although providing antioxidant defence - may lead to deficiency in other micronutrients involved in DNA metabolism and stability (such as vitamins belonging to the B group). The principal difference among various vegetarian diets is the extent to which animal products are avoided. We have performed a pilot study to determine the relationship between the micronucleus frequency in lymphocytes and diet, and we compared the levels of Vitamins C and E, beta-carotene, B(12), folic acid, homocysteine and total antioxidant capacity in healthy vegetarians and non-vegetarians. The vegetarian group, consisting of 24 volunteers (13 women and 11 men), were matched for age and sex with 24 volunteers (12 women and 12 men) with a traditional dietary habit. Among the vegetarians were 13 lacto-ovo-vegetarians with average duration of vegetarian diet 10.8 years (ranging from 5 to 26 years) and 11 lacto-vegetarians with average duration of vegetarian diet 8.2 years (ranging from 3 to 15 years). Homocysteine, Vitamins C and E and beta-carotene levels in plasma were assayed by HPLC, and serum folate and Vitamin B(12) were determined with Elecsys Immunoassay tests. The total antioxidant capacity of plasma was estimated by measuring the ferric-reducing activity in a spectrophotometric assay. Micronuclei were measured in cytokinesis-blocked lymphocytes. Vegetarians had significantly higher levels of Vitamin C and beta-carotene (but not Vitamin E) in plasma compared with non-vegetarians (P<0.001). There were no significant differences in serum levels of folic acid and Vitamin B(12) between the monitored groups. Levels of folic acid in vegetarians correlated with length of vegetarianism (r=0.62, P=0.001, N=24). Vegetarians had elevated levels of homocysteine compared with non-vegetarians (P=0.007), as did vegetarian women compared with non-vegetarian women (P=0.031). We did not find any differences in total antioxidant capacity or in micronucleus frequency between the groups. Micronuclei correlated with age (r=0.62, P<0.001, N=48), women having higher frequencies than men. Multifactorial regression analysis showed significant effects of age, sex and total antioxidant capacity on micronucleus frequency (N=48, P<0.001).

Conditions predisposing to metabolic syndrome (MetS) are associated with increased oxidative stress and inflammation. We studied, in vegetarians (n = 90) and omnivores (n = 46), the impact of the dietary regimen on the occurrence of MetS risk factors (RFs: BMI, blood pressure, glucose metabolism and lipid profile) in relation to oxidative status (advanced glycation end products (AGEs), advanced oxidation protein products (AOPPs), malondialdehyde, ferric reducing ability of plasma, vitamins A, E, C, beta-carotene and superoxide dismutase activity) and microinflammation (C-reactive protein, leukocytes and neopterin). The proportion of subjects without/positive for one or two MetS RFs was comparable between the groups. From the components of MetS only immunoreactive insulin levels differed significantly (95% CI: omnivores: 5.0-7.1 microU/mL, vegetarians: 4.5-5.4, p = 0.03). Omnivores had lower AOPP (omnivores: 0.29-0.36 micromol/g albumin, vegetarians: 0.36-0.52, p = 0.01) and beta-carotene levels than vegetarians, they consumed more calories, proteins, fat and saturated fatty acids, and less fibres, beta-carotene and vitamin C. Multiple regression analysis revealed vitamin E and AOPP levels as the most important independent determinants of MetS RFs. The vegetarian diet seems to exert beneficial effects on MetS RFs associated microinflammation. Whether the vegetarian diet may counteract the deleterious effects of elevated AOPPs and AGEs, remains to be elucidated.

Background: Diets rich in carbohydrates with a low glycemic index and with high fiber content are associated with flat post-prandial rises of blood glucose, minimal post-prandial insulin secretion and maintenance of insulin sensitivity. Protective food commodities in the prevention of cardiovascular disease, insulin resistance syndrome or diabetes are crucial components of the vegetarian diet., Aim of the Study: Insulin resistance values were assessed in relation to different nutrition. Metabolic abnormality is a predictor of age-related diseases and can be more pronounced in obese subjects. Insulin resistance values in normal weight subjects of two different nutritional habits were correlated with age., Methods: Fasting concentrations of glucose and insulin as well as calculated values of insulin resistance IR (HOMA) were assessed in two nutritional groups of apparently healthy adult subjects (age range 19 - 64 years) with normal weight (body mass index 18.6 - 25.0 kg/m(2)): a vegetarian group (95 long-term lacto-ovo-vegetarians; duration of vegetarianism 10.2 +/- 0.5 years) and a non-vegetarian control group (107 subjects of general population on traditional western diet). Intake of energy and main nutrients (fats, saccharides, proteins) was similar in both groups., Results: Glucose and insulin concentrations and IR (HOMA) values were significantly lower in vegetarians (glucose 4.47 +/- 0.05 vs. 4.71 +/- 0.07 mmol/l; insulin 4.96 +/- 0.23 vs. 7.32 +/- 0.41 mU/l; IR (HOMA) 0.99 +/- 0.05 vs. 1.59 +/- 0.10). IR (HOMA) dependence on age was only significant in subjects on a western diet. A significant increase of IR was found already in the age range 31-40 years, compared to vegetarians and it continued in later age decades. Age independent and low insulin resistance values in vegetarians are a consequence of an effective diet prevention by long-term frequent consumption of protective food. Vegetarians had a significantly higher consumption of whole grain products, pulses, products from oat and barley., Conclusion: The results of age independent and low values of insulin resistance document a beneficial effect of long-term vegetarian nutrition in prevention of metabolic syndrome, diabetes and cardiovascular disease.

Oxidative stress plays an important role in the pathogenesis of numerous chronic age-related free radical-induced diseases. Improved antioxidant status minimizes oxidative damage to DNA, proteins, lipids and other biomolecules. Diet-derived antioxidants such as vitamin C, vitamin E, carotenoids and related plant pigments are important in antioxidative defense and maintaining health. The results of long-term epidemiological and clinical studies suggest that protective vitamin C plasma concentration for minimum risk of free radical disease is higher than 50 micromol/l. Products of oxidative damage to DNA (DNA strand breaks with oxidized purines and pyrimidines), proteins (carbonyls) and lipids (conjugated dienes of fatty acids, malondialdehyde) were estimated in a group of apparently healthy adult non-smoking population in dependence on different vitamin C plasma concentrations. Under conditions of protective plasma vitamin C concentrations (>50 micromol/l) significantly lower values of DNA, protein and lipid oxidative damage were found in comparison with the vitamin C-deficient group (<50 micromol/l). The inhibitory effect of higher fruit and vegetable consumption (leading to higher vitamin C intake and higher vitamin C plasma concentrations) on oxidation of DNA, proteins and lipids is also expressed by an inverse significant correlation between plasma vitamin C and products of oxidative damage. The results suggest an important role of higher and frequent consumption of protective food (fruit, vegetables, vegetable oils, nuts, seeds and cereal grains) in prevention of free radical disease.

Determinants of total homocysteine involve demographic (age, sex, ethnic origin), genetic (enzymatic defects of metabolic homocysteine pathways) and acquired factors (deficiency of B-group vitamins, state of health, lifestyle). Plasma levels of total homocysteine and serum levels of vitamin B12, folic acid, vitamin B6 were measured in adult apparently healthy Romany minority subjects (n=119) and compared with those levels in apparently healthy subjects of majority Slovak population (n=146). Mean homocysteine level was similar in both groups (9.92 micromol/l in the Romany vs. 9.61 micromol/l in majority group). Hyperhomocysteinemia was only observed in 3% of both ethnic probands. Vitamin B12 level was equal (301 micromol/l in the Romany and 311 micromol/ in majority group). Deficient levels were found in 4% of the Romany subjects and 9% of the majority subjects. Folic acid level was significantly lower in Romany group (11.3 nmol/l vs. 14.8 nmol/l) with deficiency in 42% of the Romany subjects vs. 28% in the majority subjects. This finding is a consequence of lower consumption of fruit, vegetables, pulses and whole grain products in the Romany group. Vitamin B6 deficiency was found in 68% of the Romany subjects and 40% of majority subjects. This vitamin is homocysteine determinant under excessive methionine intake (overnutrition with predominance of animal protein intake). As was demonstrated in a dietetic questionnaires, the Romany subjects are more frequent consumers of meat and eggs. This nutrition regime should indicate an increased homocysteine level under vitamin B6 deficiency. The results of normal homocysteine levels in the Romany population under condition of higher folic acid and vitamin B6 deficiencies, smoking and higher alcohol consumption may suggest a more effective homocysteine metabolism in relation to different ethnic origin.

Oxidative stress plays an important contributory role in the pathogenesis of age-related chronic diseases. Increased lipid peroxidation process is caused by an enhanced free radical formation together with a higher supply of substrates and by an insufficient defense by antioxidants as well. Levels of malondialdehyde to content of lipid peroxidation substrates (polyunsaturated fatty acids), promoters (homocysteine--hydroxyl radical producer) and inhibitors (essential vitamins C and E) were estimated in a group (n=92) of subjective healthy adults randomly selected from general population. The relationship of malondialdehyde levels to values of peroxidisability index of fatty acids as well as to levels of homocysteine is significantly positive linear A significant inverse linear correlation between malondialdehyde levels and natural antioxidant levels (vitamin C, vitamin E) was recorded. Lipid peroxidation products (conjugated dienes of fatty acids--initial, malondialdehyde--secondary) are significantly increased in groups of subjects with deficient levels of vitamin C (below the limit from antioxidative point of view), vitamin E and both vitamins, if compared to group with normal vitamin levels (over limit in accordance with antioxidative criterion). The results document that the deficiency in two key antioxidants for lipid peroxidation inhibition means the insufficient defense against free radicals and the increased lipid peroxidation.

Background: The vegetarian lifestyle is supposedly healthy, and differences between vegetarians and non-vegetarians in biomarkers related to diseases such as cancer might be expected., Aim of the Study: To investigate the possible role of different diets in maintaining genomic stability., Methods: The vegetarian group, consisting of 24 volunteers (13 women and 11 men), were matched for age and sex with 24 volunteers (12 women and 12 men) with a traditional dietary habit. Among vegetarians there were 13 lacto-ovo-vegetarians (8 women, 5 men) with average length of vegetarian diet 10.8 years (ranging from 5 to 26) and 11 lacto-vegetarians (5 women, 6 men) with average length of vegetarian diet 8.2 years (ranging from 3 to15). All volunteers were nonsmokers, non-consumers of alcohol and had similar education and patterns of physical activity. Chromosome aberrations, micronuclei and DNA damage (strand breaks, oxidised bases and H(2)O(2)-sensitivity) were examined in peripheral blood lymphocytes of vegetarians and non-vegetarians. Plasma antioxidant status was assessed with the FRAP assay., Results: We did not find any differences in percentage of cells with chromosome aberrations or in the frequency of micronuclei between vegetarians and non-vegetarians or between lacto-ovo and lacto-vegetarians. There was no statistically significant difference in total antioxidant capacity between the groups. The group with traditional dietary habits had significantly higher levels of oxidative DNA damage (strand breaks and oxidised purines, P = 0.005) compared with vegetarians. A significant positive correlation between age and oxidative DNA damage (net FPG-sensitive sites) was found in non-vegetarians, while there was an opposite trend towards a negative association in vegetarians. On the other hand chromosome aberrations correlated with age in vegetarians (r = 0.48, P = 0.017) but not in non-vegetarians., Conclusions: Our results indicate that a vegetarian diet can lead to a slight decrease in oxidative DNA damage in lymphocytes, but other markers of genetic stability are not affected. The lowest level of DNA damage was found in lymphocytes of lactovegetarians, (especially oxidised pyrimidines, P = 0.0017), suggesting that this diet provides some protection against oxidative stress.

Levels of conjugated dienes of fatty acids (first peroxidation product) in relation to their substrates and promotors (triacylglycerols, homocysteine, iron) as well as to their inhibitors (essential antioxidative vitamins) were assessed in a vegetarian group (n=24) and compared with subjects on a mixed diet (traditional nutrition, n=24). Positive significant linear correlation between conjugated dienes and triacylglycerols, homocysteine, iron as well as inverse relationship between conjugated dienes and vitamin E, vitamin C, beta-carotene were observed in pooled groups. Lipid peroxidation risk in vegetarians seems to be caused predominantly by hyperhomocysteinemia, whereas in a mixed diet group this was due to a higher supply of substrates or risk iron values. The incidence of only 8 % of risk conjugated diene values in vegetarians in contrast to 42 % in the group with traditional diet indicates that vegetarians have a better antioxidative status as a consequence of regular consumption of protective food.

Experimental and human studies describe the adverse effect of iron or vitamin B6 deficiencies on polyunsaturated fatty acid metabolism. Iron is present in end proteins of the delta6-desaturase enzyme complex, and vitamin B6 deficiency can affect the transmethylation reaction of proteins. Plasma polyunsaturated fatty acid content was estimated in apparently healthy subjects of the general population with no consumption of fish and low vitamin B6 serum levels (< 3 microg/l; n = 21) or with low iron serum levels (men: < 12 micromol/l; women: < 10 micromol/l; n = 16) and compared to a control group (n = 22) with normal vitamin B6 and iron serum levels (in reference range). The activities of the delta6-desaturase enzyme complex were calculated as product/precursor (conversion indices). In groups of subjects with low vitamin B6 and low iron levels, delta6-desaturase activity together with delta5-desaturase activity (conversion of alpha-linolenic/18:3,n-3/ into eicosapentaenoic acid/20:5,n-3/) as well as the conversion index of docosahexaenoic acid formation (22:6,n-3) from 22:5,n-3 (second delta6-desaturase activity) were significantly reduced. The inhibition effect on fatty acid synthesis was more pronounced in subjects with low iron levels than in those with low vitamin B6 levels. The conversion indices correlated significantly positively with vitamin B6 or iron levels., (Copyright 2004 S. Karger AG, Basel)

Oxidative DNA damage in humans could arise also from incorrect nutritional habit and life style. DNA strand breaks with apurinic/apyrimidinic sites, oxidized purines and oxidized pyrimidines were assessed in 24 subjectively healthy vegetarians (plant food, dairy products, eggs) and compared with 24 non-vegetarians (traditional diet, general population). DNA strand breaks + oxidized purines are significantly reduced in vegetarians (p<0.05), DNA strand breaks are nonsignificantly decreased. The sufficient antioxidative status (overthreshold values of natural essential antioxidants, which mean a reduced risk of free radical disease) is crucial in free radical defense. Intake of protective food commodities (fruit, vegetables, dark grain products, grain sprouts, oil seeds) is significantly higher in vegetarians. Alternative nutrition subjects have a significantly increased plasma levels of vitamin C, vitamin E, beta-carotene with high incidence of overthreshold values (92% vs. 42% - vitamin C, 67% vs. 33% - vitamin E, 67% vs. 17% - beta-carotene). There is recorded a significant inverse linear correlation between values of DNA strand breaks + oxidized purines and vitamin C or beta-carotene levels (p<0.01, p<0.05). Vegetarian diet is significantly more rich source of antioxidants. The results of reduced endogenous DNA damage and higher antioxidative status in vegetarians document that a correct vegetarian nutrition might represent an effective cancer prevention.

Prevalence of mild hyperhomocysteinemia in vegetarians and vegans is a consequence of vitamin B12 deficiency. Clinical study of homocysteine reduction by vitamin B12 consisted of subjective healthy adults on alternative nutrition (n = 9) with vitamin B12 deficiency and with mild hyperhomocysteinemia. Vitamin B12 treatment was implemented by 5 intramuscular cyanocobalamin injections of a total content of 2200 micrograms during two weeks. Homocysteine level was significantly reduced (from 22 mumol/l to 11.7 mumol/l; individual reduction 29-55%). Vitamin B12 concentration in blood was significantly increased (from 152 pmol/l to 277 pmol/l; individual % of increase 63-150). The results show a high effect of vitamin B12 treatment in homocysteine value reduction of subjects on alternative nutrition.

Background: Vitamin B12, folate and vitamin B6 are the main determinants of homocysteinemia. These B-group vitamins influence two metabolic pathways of homocysteine reduction, which prevail in dependence to methionine intake. Transsulfuration (vitamin B6) dominates under condition of overnutrition with prevalence of animal food sources, remethylation (vitamin B12 and folic acid) is decisive under conditions of malnutrition, alternative nutrition or optimal traditional diet., Methods and Results: Plasma homocysteine and folic acid, vitamins B12 and B6 in serum were measured in alternative nutrition groups of adults (vegans, vegetarians (lacto + lactoovo), semivegetarians, n = 39) and compared with those values in group consuming traditional diet--control group, general population (n = 35). In alternative nutrition groups, the average homocysteine level is significantly higher (vegans 17.2 mumol/l, vegetarians 12.9 mumol/l, semivegetarians 10.1 mumol/l, control group 9.9 mumol/l); the frequency of hyperhomocysteinemia (over 15 mumol/l) is 50%, 32%, 14% vs. 6% in control group. Vegetarians and vegans have a significantly higher levels of vitamin B6 and folic acid; the frequency of vitamin B6 deficit is 60% and 57% in control group and semivegetarian group vs. 16% and 0% in vegetarian and vegan group. Folate deficit was found in 16% of traditional group vs. 0% in alternative groups. Serum levels of vitamin B12 are significantly reduced in subjects consuming alternative nutrition with deficiency observed in 67% of vegans, 32% of vegetarians, 14% of semivegetarians vs. 0% in control group., Conclusions: Vitamin levels in relation to nutritional regime and metabolic pathways of homocysteine show that the mild hyperhomocysteinemia in alternative nutrition is a consequence of vitamin B12 deficiency. In traditionally fed population, higher plasma homocysteine values is caused by folate deficiency. These conclusions are supported by a significantly negative linear correlation of homocysteine--folic acid levels (traditional nutrition) and homocysteine--vitamin B12 levels (alternative nutrition). In case of vitamin B6, a similar correlation was not found.

Advanced glycation end products (AGEs) may play an important adverse role in process of atherosclerosis, diabetes, aging and chronic renal failure. Levels of N(epsilon)-carboxymethyllysine and fluorescent AGE values were estimated in two nutritional population groups--alternative group (vegetarians--plant food, milk products, eggs) and traditional group (omnivorous subjects). Vegetarians have a significantly higher carboxymethyllysine content in plasma and fluorescent AGE values. Intake of proteins, lysine and monosaccharides as well as culinary treatment, consumption of food AGEs (mainly from technologically processed products) and the routes of Maillard reaction in organism are the substantial sources of plasma AGEs. Vegetarians consume less proteins and saccharides. Lysine intake is significantly reduced (low content in plant proteins). Subjects on alternative nutrition do not use high temperature for culinary treatment and consume low amount of technologically processed food. Fructation induced AGE fluorescence is greater as compared with that induced by glucose. It is due to higher participation of a more reactive acyclic form of fructose. Intake of vegetables and fruit with predominance of fructose is significantly higher in vegetarians. Comparison of nutrition and plasma AGEs in vegetarian and omnivorous groups shows that the higher intake of fructose in alternative nutrition of healthy subjects may cause an increase of AGE levels.

Background: Evidence indicates that food-derived Maillard's reaction products are absorbed and yet can be detected in the circulation., Aim of the Study: We postulated that consumption of the heat-treated food by omnivores could be reflected by higher plasma levels of advanced glycation end products (AGEs) in comparison with vegetarians, who in cooking (by keeping away from meat) use lower temperatures and less time for heating., Methods: Plasma fluorescent AGEs (350/450 nm) and N(epsilon)-(carboxymethyl)lysine (CML, competitive ELISA) levels were investigated in 3 groups of healthy vegetarians (9 vegans-V, 19 lactoovo-vegetarians--VLO and 14 semi-vegetarians--VS) and compared with those of age-matched omnivores (O, n=19). Mean duration of vegetarian diet was V: 7.2 +/- 1.0,VLO: 8.2 +/- 0.8 and VS: 7.9 +/- 1.1 years., Results: Both fluorescent AGE (O: 9.9 +/- 0.5; V: 10.8 +/- 0.7, LO: 13.1 +/- 0.8* and SV: 11.6 +/- 1.2 x 10(3) AU), and CML levels (O: 427.1 +/- 15.0,V: 514.8 +/- 24.6*, LO: 525.7 +/- 29.5**, SV: 492.6 +/- 18.0* ng/ml) were significantly lower in omnivores than in vegetarians. Plasma glucose, parameters of renal function (plasma concentration of creatinine and cystatin C, calculated glomerular filtration rate--GFR) as well as C-reactive protein levels were within the normal range and did not differ significantly between the groups. Thus, neither decline of kidney function nor inflammatory processes contributed to the rise in plasma AGEs., Conclusion: Enhanced plasma AGE levels in vegetarians in comparison to omnivores are herein presented for the first time. Mechanisms of AGE elevation and potential pathophysiological relevance of this finding are to be elucidated in prospective studies.

The oxidation of low-density lipoproteins (LDL) and high-density lipoproteins (HDL) and fatty acid composition, which may affect the resistance of lipoproteins to oxidation, were determined in 24 lacto-ovo vegetarians. Vegetarian diets contain more essential polyunsaturated fatty acids (PUFAs). Therefore, the relationship between LDL and HDL oxidation resistance measured by the kinetics of the formation of fatty acid conjugated dienes (lag time, maximal rate of oxidation and maximal amount of conjugated dienes), LDL and HDL fatty acid composition and vitamin E content were evaluated. All parameters of in vitro oxidation were significantly lower in HDL when compared with LDL. The relative values of arachidonic, dihomo-gamma-linoleic and docosahexaenoic acid were significantly higher in HDL, alpha-linolenic acid content significantly lower, when compared with LDL; the peroxidizability index was significantly higher in HDL. The content of vitamin E was found more than 2-fold lower in HDL particles. The results show the importance of fatty acid composition in the resistance of LDL and HDL to oxidation and from this aspect, the composition of LDL isolated from vegetarians seems to be more favourable compared to HDL., (Copyright 2001 S. Karger AG, Basel)

Values of homocysteine and lipid parameters were measured in groups of adults consuming alternative nutrition (vegetarians/lactoovo/, vegans) and compared with a group consuming traditional diet (omnivores, general population). Frequency of hyperhomocysteinemia was 53% in the vegans group, 28% in vegetarians vs. 5% in omnivores. In conditions of lower methionine intake (reduced content in plant proteins), the remethylation pathway of homocysteine metabolism prevails and it is vitamin B12 and folate-dependent. The intake of vitamin B12 is equal to zero in vegans; vegetarians consume 124% of the RDA vs. 383% in omnivores. Serum vitamin levels are significantly lower in subjects consuming alternative nutrition with deficiency observed in 24% of vegetarians, 78% of vegans vs. 0% in omnivores. Serum folate levels are within the reference range in all groups. Mild hyperhomocysteinemia in the groups consuming alternative diet is a consequence of vitamin B12 deficiency. Vegetarians and vegans meet the RDA for energy and fat, and have a favourable proportion of saturated, mono- and polyunsaturated fatty acids on total energy intake; the ratio of linoleic/alpha-linolenic acid in their diet corresponds with the recommendations. They have low cholesterol consumption and higher vitamin E and C intake. Optimal fat intake of correct composition is reflected in lower values of atherosclerosis risk factors (cholesterol, LDL-cholesterol, atherogenic index, saturated fatty acids, triacylglycerols), and significantly higher levels of protective substances (linoleic acid, alpha-linolenic acid, HDL-cholesterol, vitamin E, vitamin E/cholesterol, vitamin C). Low lipid risk factors but higher findings of mild hyperhomocysteinemia in vegetarians mean a diminished protective effect of alternative nutrition in cardiovascular disease prevention.

Background: In comparison to food habits of non-vegetarians alternative nutrition bears several risks, but it also has beneficial effects. Considering risks represent a significant age aspect. Nutritional risk and protective factors were evaluated in a adolescent group., Methods and Results: Food habits of 53 lactoovovegetarians (mean duration of vegetarianism 3.2 y) assessed by analysis of dietary questionnaires were compared to those of 55 nonvegetarians and evaluated with respect to basic biochemical indicators (iron, hemoglobin, calcium, total protein, cholesterol, fatty acids, vitamin A, beta-carotene, vitamin C, vitamin 3). Vegetarians consume less fat, and they have higher intake of plant fat, which is reflected din more favourable lipid levels, i.e. lower risk parameters of atherosclerosis (cholesterol, LDL-cholesterol, atherogenic index, saturated fatty acids) and higher values of factors with antisclerotic effect (32.9% ratio of HDL-cholesterol vs. 30.6% in non-vegetarians, polyunsaturated fatty acids, vitamin E/cholesterol ratio, vitamin C). Total plasma protein levels are balanced in both groups (intake of full value mixture of amino acids from grains, legumes (soya), and mild in vegetarians, similar intake of total proteins with a small difference in plant protein consumption). Iron and calcium absorption is inhibited in vegetarians as a consequence of presence of plant food--physic acid, oxaloacetic acid (20.7% hyposiderinemia vs. 0% in non-vegetarians, high iron intake in both groups, iron from plant sources represented 82% in vegetarian boys and 95% in vegetarian girls, hypocalcemia in 28% of vegetarians vs. 7.3% of non-vegetarians). Vegetarians have significantly higher levels of all antioxidant vitamins. This is result of higher consumption of vegetables, fruit, plant fat and sprouts. Higher intake and higher levels of antioxidants are reflected in significantly lower lipoperoxidation values., Conclusions: Lactoovovegetarian nutrition represents risk for adolescents if the values of iron and calcium are considered, however it has positive aspects on lipid parameters, protein values, and antioxidant parameters.

Plasma carnitine levels were measured in two alternative nutrition groups--strict vegetarians (vegans) and lactoovovegetarians (vegetarians consuming limited amounts of animal products such as milk products and eggs). The results were compared to an average sample of probands on mixed nutrition (omnivores). Carnitine levels were correlated with the intake of essential amino acids, methionine and lysine (as substrates of its endogenous synthesis), since the intake of carnitine in food is negligible in the alternative nutrition groups (the highest carnitine content is in meat, lower is in milk products, while fruit, cereals and vegetables contain low or no carnitine at all). An average carnitine level in vegans was significantly reduced with hypocarnitinemia present in 52.9% of probands. Similarly, the intake of methionine and lysine was significantly lower in this group due to the exclusive consumption of plant proteins with reduced content of these amino acids. Carnitine level in lactoovovegetarians was also significantly reduced, but the incidence of values below 30 micromol/l was lower than in vegans representing 17.8% vs. 3.3% in omnivores. Intake of methionine and lysine was also significantly reduced in this group, but still higher compared to vegans (73% of protein intake covered by plant proteins). Significant positive correlation of carnitine levels with methionine and lysine intake in alternative nutrition groups indicates that a significant portion of carnitine requirement is covered by endogenous synthesis. Approximately two thirds of carnitine requirement in omnivores comes from exogenous sources. The results demonstrate the risks of alternative nutrition with respect to the intake of essential amino acids, methionine and lysine, and with respect to the intake and biosynthesis of carnitine.

Background: Low protein quality and quantity is reported to be a possible risk of alternative nutrition. Pulses contain 18-41% of methionine in relation to reference protein, moreover, its content in cereals is by one half lower. Therefore vegetarians and vegans may have an insufficient intake of sulphur-containing amino acids that may subsequently affect glutathione values (precursors of its synthesis)., Methods and Results: In groups of adults on an alternative diet--lactoovovegetarians (n = 47) and vegans (n = 44) aged 19-62 years with average duration on a vegetarian or vegan diet of 7.6 and 4.9 years, respectively, glutathione levels (GSH) were measured in erythrocytes (spectrophotometrically), as well as the activity of GSH-dependent enzymes. As nutritional control (n = 42) served an average sample of omnivores selected from a group of 489 examined, apparently healthy subjects of the same age range living in the same region. One to low protein intake (56% of RDA) exclusively of plant origin significantly lower levels of total proteins were observed in vegans with a 16% frequency of hypoproteinaemia (vs 0% in omnivores). In comparison to omnivores a significantly lower glutathione level was found (4.28 +/- 0.12 vs 4.84 +/- 0.14 mumol/g Hb, P < 0.01). Lactoovovegetarians because of their protein intake in adequate amounts with a 27% proportion of animal proteins (dairy products, eggs) consume a balanced mixture of amino acids, which is reflected in total protein levels similar to omnivores and significantly higher values of glutathione -5.26 +/- 0.12 mumol/g Hb, P < 0.05 (intake of glutathione in diet, higher consumption of fruit and vegetable in comparison to omnivores). A sufficient supply of glutathione as the substrate for enzymatic reactions of hydrogen peroxide or lipid hydroperoxide catabolism, as well as for detoxication of xenobiotics, was reflected in lactoovovegetarians in a significantly higher activity of glutathione-peroxidase and glutathione-S-transferase in erythrocytes., Conclusions: Low protein intake exclusively of plant origin, significantly lower protein levels with 16% frequency of hypoproteinaemia, significantly lower glutathione values in blood in comparison to omnivores and lactoovovegetarians confirm the risk of a vegan diet also in adult age.

The aim of the present study was to assess serum levels of copper and zinc levels and erythrocytes Cu,Zn-SOD activity and to determine probable changes in gastric and colorectal precancerous diseases, benign breast diseases, gastric, colorectal and breast cancer. The study included 165 subjects with cancer, 348 subjects with precancerous (atrophic gastritis, gastric adenoma, colon adenoma, rectal adenoma) and/or benign diseases (weak dysplasia, severe dysplasia, fibroadenoma, cystic disease) and 161 randomly selected healthy controls. Our results suggest that while in gastric and colorectal cancer there were mostly increased copper levels, in breast cancer they were not changed. Zinc levels were weakly decreased in atrophic gastritis, gastric adenoma and breast cancer. There was a strong positive correlation between zinc levels and SOD activity in fibroadenoma and a weak positive correlation in colorectal adenoma and colorectal cancer without any correlation between SOD activity and copper in these groups. In gastric precancerous disease there was a positive correlation between SOD and copper. The results of this study suggest that serum trace element levels and activity of related enzymes might be different in various neoplastic processes. This variation in neoplastic processes might be influenced by other factors that have to be considered in complex relationships between the whole body and neoplastic cells.

Vegetarian food with a higher content of natural antioxidants may decrease the risk of developing cardiovascular diseases. The oxidative modification of low-density lipoprotein (LDL) has been implicated in the pathogenesis of atherosclerosis. The objectives of this study were to investigate in vitro resistance of LDL against oxidation and antioxidative status of plasma in 19 lactoovovegetarians and nonvegetarians (n = 19). The kinetics of conjugated diene formation (lag time and maximal rate of oxidation, Vmax) and thiobarbituric acid reacting substances (TBARS) were determined as indices of LDL oxidation. No significant differences in lag time and Vmax were observed between vegetarians and nonvegetarians, while TBARS in native and oxidatively modified LDL were significantly lower in vegetarians. Plasma vitamin (C, E, beta-carotene) levels were increased in vegetarians, but only the vitamin C increase was statistically significant. Vegetarians also had a significantly increased plasma total antioxidant status (TAS) and molar ratio vitamin E/cholesterol which indicates a more effective protection of lipoproteins against oxidation. A significant positive correlation was observed between lag time and plasma TAS in both vegetarians and nonvegetarians. We conclude that although the resistance of LDL to in vitro oxidation, as measured by the kinetics of conjugated diene formation was not altered in vegetarians, the effect of vegetarian nutritional habits favorably affected TBARS levels in LDL and total plasma antioxidant capacity.

The authors summarize the health risks and advantages of alternative nutrition-lactovegetarian, lactoovovegetarian and vegan. These dietary patterns involve risk in particular during pregnancy, lactation and for the growing organism. Veganism excluding all foods of animal origin involves the greatest risk. General nutritional principles for the prevention of cardiovascular diseases, oncological diseases and diabetes are fully met by the vegetarian diet. Vegetarians and vegans have low risk factors of atherosclerosis and conversely higher levels of antisclerotic substances. Overthreshold values of essential antioxidants in vegetarians imply a protective action against reactive metabolic oxygen products and toxic products of lipid peroxidation and may reduce the incidence of free radical diseases. The authors also draw attention to some still open problems of vegetarianism (higher n-3 fatty acids, taurine, carnitine). In the conclusion semivegetarianism is evaluated.

To evaluate the health and nutritional status of children with two different nutritional habits, the authors examined 26 vegetarians (lacto- and lacto-ovo; an average period of vegetarianism 2.8 years) and 32 individuals on mixed diet (omnivores) in the age range 11-14 years. Vegetarian children had significantly lower erythrocyte number as well as reduced levels of haemoglobin and iron compared to omnivores. The average level of iron did not reach the lower limit of the physiological range and hyposiderinemia was found in 58% of vegetarians vs 9% of omnivores. Reduced iron levels were observed in spite of increased intake of vegetable iron sources and vitamin C (which facilitates the conversion to ferro-form). This reduction can be attributed to the absence of animal iron sources with high utilizability and to lower iron utilization in the presence of phytic acid (higher intake of grains compared to omnivores). The incidence of hypoalbuminemia and hypoproteinemia in vegetarian children was 38 and 12%, respectively, compared to 0% in omnivores. The protein mixture from milk, eggs and vegetable sources is complete, but vegetarian children had significantly reduced intake of milk and dairy products. Favourable lipid and antioxidant parameters in vegetarian children reflect the optimal nutrition composition with respect to the prevention of free radical diseases. Such a nutrition results in significantly lower levels of cholesterol and LDL-cholesterol compared to omnivores and significantly higher and over threshold values of essential antioxidants--vitamin C, vitamin E/cholesterol (more effective protection against LDL oxidation), beta-carotene, vitamin A.

The plasma profile of fatty acids has been observed in 27 vegetarian adults, their age ranging from 20 to 63 years (13 men, 14 women) with the average period of vegetarian dietary pattern being 8.8 years. A third of the men and a half of the women were lacto-vegetarians, the rest of them were lacto-ovo-vegetarians. The contents of saturated and monounsaturated fatty acids insignificantly decreased in vegetarians when compared with non-vegetarians (n = 26, 12 men, 14 women, average group of non-smokers with mixed nutrition). The results of parameters regarded as positive factors in vegetarian diet and effective in prevention of atherosclerosis are as follows: significantly higher values of linoliec acid C 18:2, a significantly higher ratio of linoliec/leic acids C 18:2/C18:1 and insignificantly higher value of linolenic acid C 18:3, together with an unchanged, or moderately decreased contents of poly-unsaturated fatty acids C 20:4 (arachidonic acid) and C 22:6 (n3; docosahexaenoic acid). Further prooxidative-antioxidative parameters were selected in regard to the theoretical anticipation of risk brought about by increased lipoperoxidation in vegetarians (poly-unsaturated fatty acids-substrate of the process) which is significant in the etiology of cardio-vascular and oncologic diseases. Their favourable values (significantly lower plasma contents of conjugated dienes of fatty acids, significantly higher plasma value of vitamin C, Beta-carotene, vitamin E/cholesterol-protection of LDL, vitamin E/triacylglycerols-protection of fatty acids, 3.5 times more significant positive linear correlation of vitamin E/triacylglycerol versus plasma contents of C 18:2) eliminate the risk of increased lipoperoxidation in vegetarians. (Tab. 3, Fig. 1, Ref. 29.)

Parameters of lipid metabolism (triacylglycerols TG, cholesterol CH, HDL-CH, LDL-CH, atherogenic index AI, profile of fatty acids) were measured in blood samples of 81 healthy lacto and lacto-ovo vegetarians (42 males, 39 females; age range 19-39 years). The average period of being on a vegetarian diet was 6.2 years. Low levels of TG, CH, LDL-CH, AI and HDL-CH values on the borderline between standard and reduced risk (1.4 mmol.l-1) can be considered as favourable from the atherosclerosis prevention aspect. Compared with non-vegetarians (n = 62), the levels of TG, CH, LDL-CH, and AI are significantly reduced in the vegetarian group. As opposed to non-vegetarians, vegetarians showed a higher total sum of polyunsaturated fatty acids, a significantly higher content of linoleic acid (C 18:2) and linolenic acid (C 18:3), unchanged content of oleic acid (C 18:1), stearic acid (C 18:0) and other polyunsaturated fatty acids. The process of lipoperoxidation (with polyunsaturated fatty acids as substrate) is involved in the etiology of cardiovascular and oncological diseases. Favourable values of prooxidative-antioxidative parameters demonstrated a reduced risk of lipoperoxidation in vegetarians, compared to non-vegetarians (significantly reduced content of conjugated dienes of fatty acids in plasma, significantly higher plasma levels of vitamin C, beta-carotene, vitamin E/cholesterol ratio--and indicator of LDL protection, vitamin E/triacylglycerols ratio--an indicator of fatty acid protection--, selenium and glutathione-peroxidase activity).

The effect of cadmium intake (100 micrograms/kg body weight/day as cadmium chloride over a period of three months) on the prooxidative-antioxidative state of liver was studied in 30 days old weaned male rats. Animals were fed a nutritionally balanced lacto-vegetable diet containing high-quality amino acid mixture (casein + gluten 1:1), lipids in form of either pork fat PF (% of polyunsaturated fatty acids PUFA = 11.9; unsaturation index UI = 72), margarine MA (% PUFA = 21.9; UI = 98), or soybean oil SO (% PUFA = 61.2; UI = 156) and vitamin E at amount of 60 mg/kg of food (groups PF, PF + Cd, MA, MA + Cd, SO, SO + Cd) or 600 mg (groups PF + Cd + E, MA + Cd + E, SO + Cd + E) in form of alpha-tocopheryl acetate. The following parameters were measured: conjugated dienes of fatty acids (CD), activities of superoxide dismutase (SOD), catalase (CAT) (as relative generation of H2O2) and glutathione peroxidase (GSH-Px). A direct relation between lipoperoxidation values and unsaturation index of lipids was found both in spontaneous (PF, MA, SO-control) and cadmium-induced generation of free oxygen radicals. Cadmium intake resulted in a disbalance in prooxidative-antioxidative processes which was manifested in a significant increase of CD in all fat sources (the degree of increase was directly proportional to UI and PUFA), in similar values of relative H2O2 generation and in a nonsignificant increase of GSH-Px in animals with most developed lipoperoxidation (SO). A tenfold increase in the administered dose of vitamin E restored a prooxidative-antioxidative equilibrium disturbed by cadmium intake in the liver of rats fed the diet with animal fat (PF + Cd + E) and margarine (MA + Cd + E) (reduction of CD to the level of control groups, decrease of relative generation of H2O2-significant in MA). In animals fed with soybean oil, a vitamin E-induced reduction of CD was significantly over the control level simultaneously with significant stimulation of GSH-Px activity. No changes in H2O2 generation together with CD levels and GSH-Px activity indicated that a synergic effect of several antioxidants is essential in the case of high lipoperoxidation. Presented results are important with respect to possible control or regulation of the equilibrium between prooxidative and antioxidative processes by nutrition.

Age dependence of lipid peroxidation levels estimated as conjugated dienes (CD) of plasma fatty acids was investigated in vegetarian and non-vegetarian males and females aged 11-14, 15-18, 19-39 and 40-60 years. The increase of CD levels with age was found in probands on both types of nutrition up to the age of 40 years. In the first three age groups, lipid peroxidation was insignificantly lower in vegetarians when compared to nonvegetarians. The increase of conjugated dienes was on the level of significance (p < 0.05) in the oldest vegetarians vs nonvegetarians. Therefore, content of defense parameters--antioxidative vitamin and enzyme--was estimated in blood of vegetarians aged 40-60 years. Significantly higher levels of vitamin C and catalase activity were found in vegetarians (C-63.6 and 86.5 mumol/l; CAT-1497 and 1313 U/ml for males and females, respectively) when compared to nonvegetarians (C-41.3 and 54.4 mumol/l; CAT-1192 and 1086 U/ml). A significant negative linear correlation (p < 0.001) for CD-C and CD-CAT was found in both sexes of vegetarians and in nonvegetarian females (p < 0.05 for nonvegetarian males). Important finding is a more pronounced in vegetarians (2.5-3.4 times higher slope of regression lines) indicating positive effect of vegetarian nutrition on efficiency of protection system.

Fatty acid profile in plasma was examined in 12 adult vegetarians (lacto and lacto-ovo) aged 41-63 years with an average period of vegetarian nutrition of 9.8 years. Difference in the content of saturated and monounsaturated fatty acids in vegetarians was insignificant (compared to non-vegetarians). Positive factor of vegetarian nutritional habit with respect to atherosclerosis included significantly elevated content of linoleic acid (C 18:2) and linolenic acid (C 18:3), as well as unchanged or only slightly reduced content of polyunsaturated fatty acids--arachidonic acid (C 20:4) and docosahexaenoic acid (C 22:6, n = 3). Favourable values of prooxidative-antioxidative parameters (significantly reduced content of conjugated dienes of fatty acids in plasma, significantly higher plasma levels of vitamin C, beta-carotene, vitamin E/cholesterol--indicator of LDL protection and vitamin E/triacylglycerols--indicator of fatty acid protection) demonstrated a reduced risk of lipoperoxidation in vegetarians.

The authors subdued 183 vegetarians to examination, the aim of which was to judge the state of health and nutrition of the vegetarian population. The examined group was composed of people with their age ranging from 19-60 years, out of which 102 were of younger (19-39 years) and 81 were of older age. Their average period of vegetarian food consumption was 4.2 years. One third of men and a half of women were lacto-vegetarians, the rest were lacto-ovo-vegetarians. The results were compared with 160 nonvegetarians (64 of younger and 96 of older age). The detected values of lipid parameters were evaluated as favourable for vegetarians (low values of cholesterol, triacylglycerols, atherogenic index, LDL-cholesterol, the share of HDL-cholesterol was 28-33% (vs 24-26% in nonvegetarians) with values converging to 1.4 mmol.l-1--i.e. reduced risk). Additional favourable factors in prevention of atherosclerosis include the absence of obesity in vegetarians and values of antisclerotic active substances in blood (high values of vitamin C, in comparison with nonvegetarians a significantly higher molar ratio of vitamin E/cholesterol and vitamin E/triacylglycerols--more effective protection against peroxidation of lipids). Vegetarian mode of food consumption may be favourably evaluated regarding prooxidative-antioxidative parameters which play an important role in the process of atherogenesis, and carcinogenesis. Significantly lower values of conjugated dienes in plasma of vegetarians and vice versa high values of antioxidant substances (vitamin C, vitamin E/lipid components, catalase activity) were detected. A more pronounced system of detoxication in vegetarians is important due to a possible risk of an increased intake of xenogenous substances. (Tab. 3, Ref. 27.)

In the conditions of physiological nutrient content and variable amino-acid mixtures made of casein K, gluten G and KG combination (1:1, standard diet), the 10-week effect of amino acids (until the age of 105 days, end of maturation stage) was investigated in growing rats with respect to protein utilization (net protein ratio) and to the values of lipid parameters at the end of the experiment (cholesterol, triacylglycerols, atherogenic indexes, cholesterol distribution into lipoprotein classes). A significant decrease in NPR for gluten, an insignificant decrease for casein in the growth period are related to the amino acid score of limiting amino acids--they determine rate of proteosynthesis and potential biological value--amount percentage of amino acids of the given diet for plastic processes of proteins (AS for KG 69, for K 67, for G 28; BHp for KG 83.1, for K 70.0, for G 54.1). Since day 105 amino acid utilization is balanced in all groups, hence it does not depend upon the quality of aminograms (lower rate of proteosynthesis in comparison with the growth period, for which the values of limiting amino acids are sufficiently high). Significantly decreased values of cholesterolemia and triacylglycerolemia for gluten food, insignificantly higher values for casein food, are in direct correlations with the values of Lys/Arg, Met/Arg, Met, Lys, and in indirect correlations with Arg and Arg+Glu+Gly. Distribution of HDL-cholesterol as a cholesterol percentage in HD lipoproteins is higher by 8.7% for gluten and all atherogenic indexes are significantly decreased in contrast to casein food, in which a slight decrease in HDL-cholesterol and insignificantly higher atherogenic indexes were recorded.

For the purpose of judgement of the vegetarian population state of health and nutrition 41 vegetarians were examined, namely university students in the age of 18-24 years, 36% of which were lacto-vegetarians and 64% lacto-ovo-vegetarians, 22 men and 19 women. Low values of cholesterol and triacylglycerols, content of HDL-cholesterol to 32% (close to the value 1.4 mmol per litre), low atherogenic index, low values of blood pressure and no case of obesity are favourable factors in the prevention of atherosclerosis. The only exception is represented by low values of vitamin C which neither in autumn period achieved the bottom value of the physiological range (low intake of fruit and vegetables). Saturation of organism with proteins is good (intake of full-value mixture of aminoacids in the form of plant and milk proteins), the values of glycemia were on the level of the bottom border of the physiological range. Low values of hematological parameters were detected. The erythrocyte count and levels of hemoglobin and hematocrit were on the bottom border of the physiological range; the values of serum iron in the bottom half of the physiological standard. The vegetarians consumed less fruit and vegetables (vitamin C facilities the conversion of the ferri-form into ferro-form), more cerials (linkage of iron with the phytic acid), and only scarcely the foliage vegetables. The incidence of anemias was equal with that in non-vegetarians in the age of 17-18 years (epidemiologic study of the institute). The supply of organism by vitamins B1,B2 and B6 were within the physiological standard.(ABSTRACT TRUNCATED AT 250 WORDS)

Lipid parameters (cholesterol CH, HDL-, LDL-cholesterol, triacylglycerols TG, atherogenic index AI) were estimated in four age groups of vegetarians, 82 males and 80 females, aged 15 to 60 years. The period of consumption of vegetarian food was 1.4 to 1.9 years for adolescents (15-18 years old) or 2.4 to 5.4 years for adults (age groups 19-29 years, 30-39 years and 40-60 years). Lacto-vegetarians constituted one half of females and one third of males. Vitamin C content, lipid peroxidation levels (conjugated dienes, CD) and the activities of catalase (CAT) and glutathione peroxidase (GSH-Px) were estimated in the oldest age group of males and females. Low levels of TG and glutathione peroxidase (GSH-Px) were estimated in the oldest age group of males and females. Low levels of TG and CH (in the lower half of the reference range), low calculated values of LDL-CH and AI, as well as values of HDL-CH in the upper region of the standard risk zone or over 1.4 mmol/l (reduced risk level) in males and females of all age groups are the positive factors of vegetarian nutrition in prevention of atherosclerosis. High levels of vitamin C in blood, absence of obesity and low blood pressure should be mentioned here as additional positive factors as well. When considered as a single isolated factor, the nearly significantly elevated values of CD (linked to increased intake of unsaturated fatty acids) could be a negative factor of vegetarian nutrition.(ABSTRACT TRUNCATED AT 250 WORDS)

Male weaning rats were put on a diet with a physiological nutrient combination adjusted for age, milk casein (E/N = 0.79) and wheat gluten (E/N = 0.30) being the sources of protein. The net protein ratio (NPR) was evaluated weekly until 140 days of age. On days 70 and 140, L-(U-14C)-tyrosine was administered intraperitoneally and 12 h later specific tyrosine activity was determined in the protein fraction of liver and muscle by measuring the incorporation of the labeled amino acid in order to assess protein synthesis over the corresponding time period. Regression lines describing the relationship between animals' weight, age and protein source suggested that the daily weight increase was 6.99 g between days 30-77, 2.97 g between days 77-105 and 0.64 g between days 105-140. Muscle tyrosine levels in rapidly growing animals aged 70 days were 91.0 micrograms/g/12 h for casein and 65.6 micrograms/g/12 h for gluten. Liver tyrosine levels were 336.4 and 189.6 micrograms/g/12 h, respectively. The differences observed at this age were highly significant. In adult animals (140 days old) there were non-significant differences between tyrosine levels in the casein- and gluten-fed groups. The isotope study clearly showed that protein synthesis was reduced in growing and developing animals on vegetable nutrition, which is deficient in essential amino acids, (especially the limiting amino acid lysine, crucial for the utilization of all other amino acids in peptide chain synthesis). The low rate of amino acid utilization found in animals younger than 105 days is consistent with the findings obtained by the isotope method.

Male len rats at the age of 30-140 days were administered a diet with an optimum content of nutrients in dependence on their age in which the source of proteins was this: milk casein (essential acid to nonessential acid ratio E/N = 0.79), soya (defatted and without inhibitors of digestive enzymes, E/N = 0.73), wheat gluten (E/N = 0.30), and their mixture (with one-third portions of each protein, E/N = 0.54). The dietary protein values were adjusted to optimum values according to the quality with respect to casein (without amino acid fortification). Protein utilization (net protein ratio NPR) was determined in weekly intervals, triacylglycerol and cholesterol concentrations in the blood serum were determined on the 70th and 140th day of age. A proteosynthesis rate was determined isotopically as L-/U-14C/-tyrosine incorporation in the protein fractions of liver and muscle in 12 hours after intraperitoneal application of the isotope in the rats in the period of rapid growth and in the adult rats on a casein--gluten diet. The isotopically determined values of tyrosine in the liver and muscles are significantly lower for the age of 70 days and gluten diet in comparison with the casein values. The proteosynthesis rate at the age of 140 days is identical. A direct relation was also found between protein utilization and the values of the amino acid score of limiting amino acids AS and the potential biological value of the diet BHp in growing rats at the age of 30-98 days (AS-K/Met + Cys/2/67, S/Met + Cys/2/63, G/Lys/28, mixture/Met + Cys/2/67; BHp-K 70.0; S 65.1; G 54.1; mixture 77.0; NPR/70 days/-K 2.00; S 1.48; G 1.22; mixture 2.07). In adult rats (from the age of 105 days) the utilization of the diet from vegetable sources is equalized with the utilization of the diet from animal sources, hence it does not depend on the aminogram quality. The results demonstrate the insufficiency of vegetable sources of food with respect to proteosynthesis and the content of limiting amino acids (decisive for the synthesis of peptide chains) in the period of the organism development. In adult rats the values of the aminograms of food vegetable sources are sufficiently high with respect to the lower rate of proteosynthesis (not for the growth but for the organism maintenance, tissue regeneration).(ABSTRACT TRUNCATED AT 400 WORDS)