Search

Summary Background & aim Several studies explored the association of vitamin B6 intake with the risk of cancers. However, it is unclear whether different doses of vitamin B6 have distinct effects on the prognosis of nasopharyngeal carcinoma (NPC) patients. This study investigated the relationship between different doses of B6 intake and the prognosis of NPC patients. Methods This retrospective cohort analysis included 792 newly diagnosed NPC patients with a median follow-up of 62.05 months. Restricted cubic spline and maximally selected rank statistics were performed to determine the cut-off value of vitamin B6 during treatment (VB6DT). Kaplan–Meier method and log-rank tests were performed to analyze survival outcomes. A multivariable Cox proportional hazard model was performed to determine the independent prognostic factors. Results NPC patients were divided into three groups according to the cut-off value of VB6DT: non-users (0 mg/d), VB6DT > 8.6 mg/d, and VB6DT ≤ 8.6 mg/d. Patients with VB6DT > 8.6 mg/d had significantly lower 5-year overall survival (OS) (83.5% vs. 90.8%, p = 0.006), distant metastasis-free survival (DMFS) (83.5% vs. 91.0%, p = 0.004), and progression-free survival (PFS) (73.7% vs. 81.7%, p = 0.011) and slightly but not significantly lower 5-year local recurrence-free survival (LRFS) (87.7% vs. 90.7%, p = 0.214) than the non-users. Patients with VB6DT ≤ 8.6 mg/d had slightly but not significantly better 5-year OS (93.3% vs. 90.8%, p = 0.283) than the non-users, while all other primary endpoints were similar (p > 0.50). Multivariable analyses confirmed that VB6DT > 8.6 mg/d was an independent negative prognostic factor of OS (p = 0.010), DMFS (p = 0.017), and PFS (p = 0.030) but not of LRFS (p = 0.428). Conclusions Excessive VB6DT higher than the cut-off value is an independent negative prognostic factor for NPC patients. Additionally, low dose intake improved OS only slightly but not significantly.

Previous evidence suggests a potential dual impact of aging and vitamin B6 (B6) deficiency on polyunsaturated fatty acid (PUFA) metabolism; gender may influence PUFA biosynthesis. Perturbation of PUFA compositions during B6 deficiency could be linked to age-related health outcomes. However, little is known about the interrelationships between vitamin B6, PUFA, and gender in the older population. Therefore, we investigated whether gender-specific associations of B6 intake and plasma pyridoxal 5’-phosphate (PLP) concentration, respectively, with plasma PUFA concentrations and ratios (eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), arachidonic acid (AA), EPA + DHA, EPA/AA, and (EPA + DHA)/AA) existed in older adults. We further examined the relationships of adequate B6 status (PLP ≥ 20 nmol/L) with high (above median) plasma PUFA relative to deficient B6 status. This cross-sectional study analyzed 461 participants aged ≥60 years from NHANES 2003–2004. Nutrient intakes were assessed using two 24-h recalls and supplement questionnaires. PLP and PUFA concentrations were measured. Multivariate linear regression assessed the association of B6 intake and PLP with PUFA; multivariate logistic regression evaluated the relationship of adequate B6 status with high plasma PUFA, adjusting for demographic, socioeconomic, and dietary factors; physical activity; smoking; alcohol; medication; and BMI. There were interactions between gender and B6 intake on EPA (P-interaction = 0.008) and AA (P-interaction = 0.004) only, whereas no interaction existed between gender and PLP on PUFA. PLP was directly associated with EPA (β = 0.181, P = 0.002), DHA (β = 0.109, P = 0.005), EPA + DHA (β = 0.14, P = 0.002), EPA/AA (β = 0.186, P = 0.004), and (EPA + DHA)/AA (β = 0.13, P = 0.026). The odds of having high plasma EPA (adjusted (a) OR: 2.03, P = 0.049) and EPA/AA (aOR: 3.83, P < 0.0001) were greater in those with adequate B6 status compared to those with deficient B6 status. In conclusion, in US older adults, a higher PLP level was associated with a greater level of EPA, DHA, EPA + DHA, EPA/AA, and (EPA + DHA)/AA. Adequate B6 status was associated with high EPA and EPA/AA status. These findings suggest that sufficient vitamin B6 status may positively influence PUFA metabolism in older adults.

Abstract. Objective: The prevalence of depression and anxiety is increasing worldwide. Diet as a modifiable factor for mental health has received great attention. The aim of the present study was to evaluate the association of vitamin B6 intake with depression and anxiety. Methods: This cross-sectional study was performed among 3362 adults in 2011. Anxiety and depression were evaluated using an Iranian validated version of the Hospital Anxiety and Depression Scale (HADS) questionnaire. Dietary intakes were evaluated by a validated 106 item self-administered Willett-format dish-based semi quantitative food-frequency questionnaire (DFQ). Results: The mean intake of vitamin B6 (mg/day) was significantly lower in anxious (1.93 ± 0.74 vs. 2.0 ± 0.74; P = 0.02) and depressed (1.86 ± 0.72 vs. 1.99 ± 0.74; P = 0.001) people than healthy participants. The lower level of vitamin B6 intake (tertile 1), after adjustment for the impacts of various confounding variables, in total population and women was associated with the higher odds of depression (OR = 1.41; 95% CI: 1.19, 2.31; P

Introduction: Palpable breast lumps are one of the most prevalent breast problems in women who visit a doctor. Most of these lumps are benign, and many of these benign lumps, have cystic nature. One of the suggested treatments for breast cyst is vitamin B6 intake. So, this study aimed to determine the effect of vitamin B6 on reducing the number and the size of breast cysts and reducing the amount of recurrence after aspiration. Materials and Methods: This study is a double-blind randomized clinical trial. Patients simply divided into two groups randomly, intervention group (receiving 150 mg vitamin B6 twice a day for two months) and control group (placebo). After data collection, the database produced, and information came in by SPSS-22 software. Descriptive results extracted in the form of tables and graphs. In all cases was used α=0.05. Results: At the end of the study, 65 patients (34 people in the intervention group, and 31 people in the control group) studied. At the end of the survey in the non-palpable cysts, was observed a significant decrease in the number and the size of breast cysts in each group receiving vitamin B6 or placebo. Still, the difference was not significant in comparing the two groups. 19 patients (2.29%) had palpable cysts that aspiration performed in all cases. After the study period, no recurrence of cysts observed in any of the intervention and control groups. Conclusion: The study showed that vitamin B6 had no effect on reducing the size and the number of non-palpable breast cysts and prevent recurrence of palpable cysts after aspiration.

Objectives: There are conflicting results for the association between vitamin B6 intake with reduced pancreatic carcinoma risk. Thus, a meta-analysis was performed to summarize the evidence...

Heart disease results from a continuous process, the heart gradually loses its ability to function normally. Early in the heart disease compensates for its inability to function and maintains normal blood circulation through an enlarged and increased pulse (compensated heart disease) (Inayati, 2014). The aim of the study was to determine the relationship between vitamin B6 intake and LDL levels in patients with coronary heart disease. This study was observational with a cross sectional design. Data on vitamin B6 intake obtained by the food recall method for 3 days. Data processing is done by person correlation test. The results showed that vitamin B6 intake of coronary heart disease (CHD) patients in hospitals. Dr. Pringadi Medan is 60% good and 35% is not good. Chronic LDL levels vary, 10% are normal, 65% are mid and 25% are high. The results of statistical tests showed that there was no relationship between vitamin B6 intake and LDL levels.

Preschool children need optimal nutrition, including a variety of nutrient-dense foods, for growth and development. The purpose of this study was to determine differences in foods and nutrients consumed at childcare and home environments. Children ages 3-to-5 years (n = 90, 3.8 ± 0.7 years; 56% female) from 16 childcare centers participated in this cross-sectional study from 2011 to 2014. Lunches at childcare were observed for two days; three days of dinners at home were reported by caregivers. Nutrient-dense and energy-dense foods were counted and nutrient content of meals was determined using FoodWorks®. More servings of fruit (0.92 ± 0.82 vs. 0.15 ± 0.26; p ≤ 0.0001), vegetables (1.47 ± 1.43 vs. 0.62 ± 0.60; p ≤ 0.0001), and low-fat dairy (0.83 ± 0.32 vs. 0.07 ± 0.19; p ≤ 0.0001) were consumed at childcare than at home. More servings of high-fat, high-sugar foods (0.08 ± 0.18 vs. 0.43 ± 0.39, p ≤ 0.0001) and sugary drinks (0.22 ± 0.41 vs. 0.39 ± 0.35. p ≤ 0.001) were consumed at home than at childcare. There were no differences between environments in whole-grains, high-fat meats, or high-fat high-sugar condiments consumed. On average, children consumed 333.0 ± 180.3 kcal at childcare and 454.7 ± 175.3 at home (p ≤ 0.0001). There were no differences in macronutrient profiles or in iron, zinc, folate, or vitamin B6 intake. More calcium (86.2 ± 44.6 vs. 44.6 ± 22.2 mg/kcal, p ≤ 0.0001) and vitamin A/kcal (56.1 ± 36.9 vs. 26.5 ± 24.2 RAE/kcal, p ≤ 0.0001) were consumed at childcare than at home. Preschool children are consuming more nutrient-dense foods and a more servings of fruit and vegetables at childcare during lunch than at home during dinner. Childcare and parents should work together to provide early and consistent exposure to nutrient-rich foods to ensure optimal nutrition for developing children., Highlights • More fruits, vegetables, and low fat dairy are consumed at childcare than at home. • More high-fat high-sugar foods and drinks are consumed at home than childcare. • More energy is consumed at home than childcare. • Childcare and families can work together to ensure optimal nutrition for children.

Objectives: We performed this meta-analysis to estimate the association between vitamin B6 intake and colorectal cancer risk. Methods: Prospective cohort studies on vitamin B6 intake and colorectal cancer risk were identified by searching databases from the period of 1960 to 2016. Results from individual studies were synthetically combined using Stata 13.0 software. Results: A total of 10 prospective cohort studies including 13 data sets were included in our meta-analysis, containing 7,817 cases and 784,550 subjects. The combined relative risks (RR) of colorectal cancer for the highest vitamin B6 intake compared with the lowest vitamin B6 intake was 0.88 [95% confidence intervals (CIs): 0.77–1.02]. Dose-response meta-analysis based on five eligible studies showed that for each additional 3 and 5 mg of vitamin B6 intake, the risk would decrease by 11% (RR: 0.89, 95%CI: 0.81–0.98) and 17% (RR: 0.83, 95%CI: 0.71–0.97), respectively. Little evidence of publication bias was found. Conclusion: This meta...

The interaction of levodopa and vitamin B6 is a well-known issue. This study investigated the incidence of unacceptable intake levels of vitamin B6 among levodopa users by means of a systematic review. We searched two databases (PubMed and "Igaku Chuo Zasshi") for articles about adverse events due to the interaction of levodopa and vitamin B6 published up to August 2017. Of 98 citations retrieved, 11 studies met the selection criteria. The results indicated that a vitamin B6 intake level of more than 50 mg/day could reduce the efficacy of levodopa. The recommended intake of vitamin B6 for Japanese adults is 1.4 mg/day for men and 1.2 mg/day for women. Therefore, the acceptable intake of vitamin B6 for levodopa patients would be within the range of the recommended intake level, which is also within the usual range in foods in Japan, except for dietary supplements or health foods. Levodopa users should be cautious about taking dietary supplements and over-the-counter drugs.

This paper explores the prevalence and predicting factors of depression in older Korean community-dwelling adults, giving special attention to nutrition and social support. Data from male (n = 123) and female (n = 135) older adults were collected in two senior centers in 2009. We found that depression was present in 17.1%. No significant gender difference was found in the prevalence of depression although the predicting factors were gender specific. In male participants, deficient protein intake, having more chronic diseases, and having a subjective perception of difficulties in mastication were predicting factors for depression, whereas deficient vitamin B6 intake, lower cognition, and lack of social support were predicting factors in female participants. The high prevalence of depression, regardless of gender, highlights the urgent need to screen depressed elders. The different predicting factors for depression in male and female older adults suggest a need to develop gender-specific interventions to alleviate depressive symptoms.

BACKGROUND/OBJECTIVES Recent research regarding vitamin B6 status including biochemical index is limited. Thus, this study estimated intakes and major food sources of vitamin B6; determined plasma pyridoxal 5'-phosphate (PLP); and assessed vitamin B6 status of Korean adults. MATERIALS/METHODS Three consecutive 24-h diet recalls and fasting blood samples were collected from healthy 20- to 64-year-old adults (n = 254) living in the Seoul metropolitan area, cities of Kwangju and Gumi, Korea. Vitamin B6 intake and plasma PLP were analyzed by gender and by vitamin B6 supplementation. Pearson's correlation coefficient was used to determine associations of vitamin B6 intake and plasma PLP. RESULTS The mean dietary and total (dietary plus supplemental) vitamin B6 intake was 1.94 ± 0.64 and 2.41 ± 1.45 mg/day, respectively. Median (50th percentile) dietary intake of men and women was 2.062 and 1.706 mg/day. Foods from plant sources provided 70.61% of dietary vitamin B6 intake. Only 6.3% of subjects consumed total vitamin B6 less than Estimated Average Requirements. Plasma PLP concentration of all subjects was 40.03 ± 23.71 nmol/L. The concentration of users of vitamin B6 supplements was significantly higher than that of nonusers (P < 0.001). Approximately 16% of Korean adults had PLP levels < 20 nmol/L, indicating a biochemical deficiency of vitamin B6, while 19.7% had marginal vitamin B6 status. Plasma PLP concentration showed positive correlation with total vitamin B6 intake (r = 0.40984, P < 0.0001). CONCLUSIONS In this study, vitamin B6 intake of Korean adults was generally adequate. However, one-third of subjects had vitamin B6 deficiency or marginal status. Therefore, in some adults in Korea, consumption of vitamin B6-rich food sources should be encouraged.

Objectives This study estimated dietary vitamin B6 intake and its food sources in young Koreans by using a modified Korean vitamin B6 database. Methods Dietary vitamin B6 intake and food sources were estimated from a 3-d recall method for 294 Korean college undergraduates (149 men and 145 women, age range 17∼25 y) who had no health problems. Food portions were estimated by using standard household measurements and published average portions. Results Average daily intakes of vitamin B6 were 1.57 mg/d in men and 1.44 mg/d in women. Average consumptions of vitamin B6 were 104% of the Korean recommended dietary allowance in men for vitamin B6 and 102% in women. However, 37% of men and 32% of women subjects consumed less than 75% of the Korean recommended dietary allowance for vitamin B6. Major dietary sources of vitamin B6 for Korean young men were pork, rice, onion, potatoes, garlic, mackerel, spinach, egg, carrot, and chicken. Major dietary sources of vitamin B6 for young Korean women were rice, pork, kimchi , beef, bean sprout, potatoes, dumplings, and onions. As for major dietary sources of vitamin B6, the top 20 foods provided nearly 89% of total vitamin B6 in men and 70% of total vitamin B6 in women. Conclusions Intake of vitamin B6 by young Koreans was adequate in general, but the supply of vitamin B6 for Koreans should be based on sufficient amounts and specific food sources because fewer foods contribute to vitamin B6 intake of Koreans and these foods are mainly of plant origin and less bioavailable.

Dietary intakes and sources of vitamin B_6 in 72 healthy Korean elderly subjects (29 men, 43 women, ≥57 years of age) living in the Seoul area were estimated using a modified Korean vitamin B_6 database. The dietary vitamin B_6 intake and food sources were estimated by the three day recall method with the help of a trained interviewer. Food portion sizes were estimated using standard household measures and published average portion sizes. The average daily vitamin B_6 intake was 2.06±0.46 mg/d in elderly men, and 1.94±0.47 mg/d in elderly women. Less than 5% of elderly men and 15% of elderly women consumed less than the Korean Recommended Dietary Allowance (RDA) of vitamin B_6. The average ratios of vitamin B_6 intake to daily protein intake were 0.03±0.01 mg/g in both elderly men and women. The intake of vitamin B_6 was significantly (p＜0.01～p＜0.001) and positively correlated to intakes of all other nutrients in elderly women, but was not significantly correlated to intakes of several nutrients in elderly men. Foods from animal and plant sources provided 24% and 76%, respectively, of the total vitamin B_6. Major dietary sources of vitamin B_6 in Korean elderly were rice, soybean sprout, kimchi, pork, beef, potatoes, garlic, onion, anchovy and kochujang. The major sources accounted for most of the vitamin B_6 intake with the top 20 foods providing nearly 75～76% of the total vitamin B_6 in Korean elderly.

This study tried to examine, from epidemiological and physiologic anthropological (Japanese culture on breakfast) points of view, the integrated effects of the amount of tryptophan and vitamin B6 intake and the following exposure to sunlight on the circadian typology and sleep habits in young Japanese children aged 2 to 6 years, using the newly-evaluated calculating system of tryptophan (Tryptophan Index 2009) and vitamin B6 intake (VitaminB6 Index 2009) at breakfast. The positive and significant correlation was shown between the Morningness-Eveningness (M-E) score and the Tryptophan Index and also the Vitamin B6 Index. This positive correlation between M-E score and amount of tryptophan intake was shown only by children who were exposed to sunlight for longer than 10min after breakfast. These results might support the following hypothesis: higher tryptophan and vitamin B6 intake at breakfast could promote the synthesis of serotonin via light stimulation in the morning in children.

The moisture, protein and vitamin B6 contents of foods commonly consumed in Nigeria were determined. Subsequently, dietary protein and vitamin B6 consumption of 41 adolescents resident in a post primary Institution were assessed over a 7-day period. The vitamin B6 content of the foods as estimated by chemical method correlated strongly (r = 0·8562, P < 0·001) with values obtained from microbiological assay (using Saccharomyces uvarum as test organism). Likewise, a strong and positive correlation existed between protein and vitamin B6 content as determined by chemical assay (r = 0·3927, P < 0·02) or by microbiological assay (r = 0·7161, P < 0·002). Vitamin B6 intake of the adolescents also correlated significantly (r = 0·8741, P < 0·001) with protein intake. The daily mean vitamin B6 and protein intake was 1·5 ± 0·34 mg and 62·1 ± 13·1 g, respectively. The findings indicate that population groups that consume staple diets based on roots and tubers or those who do not meet their needs for protein would have poor vitamin B6 status. Since institutional diets are often better than diets consumed in many homes, an extensive study of vitamin B6 consumption patterns of other population groups is suggested.

The purpose of this study was to assess vitamin B(6) intake and status in Korean patients with newly diagnosed type 2 diabetes. Sixty-four patients with newly diagnosed type 2 diabetes and 8-11% glycated hemoglobin (A1C), along with 28 age-matched non-diabetic subjects, participated. Dietary vitamin B(6) intake was estimated by the 24 hour recall method and plasma pyridoxal 5'-phosphate (PLP) was measured. There was a significant difference in daily total calorie intake between the diabetic and non-diabetic groups (1,917 ± 376 vs 2,093 ± 311 kcal). There were no differences in intake of total vitamin B(6) (2.51 ± 0.91 vs 2.53 ± 0.81 mg/d) or vitamin B(6)/1,000 kcal (1.31 ± 0.42 vs 1.20 ± 0.32 mg) between the diabetic and non-diabetic groups, andI intakes of total vitamin B(6) were above the Korean RDA in both groups (180.0 ± 57.9 vs 179.0 ± 65.4). There was a higher percentage of diabetic subjects whose plasma PLP concentration was30 nmol/L compared to non-diabetic group. Plasma PLP levels tended to be lower in the diabetic subjects than in the non-diabetic subjects, although the difference was not statistically significant due to a large standard deviation (80.0 ± 61.2 nmol/L vs 68.2 ± 38.5 nmol/L). Nevertheless, plasma PLP levels should be monitored in pre-diabetic patients with diabetic risk factors as well as in newly diagnosed diabetic patients for long-term management of diabetes, even though this factor is not a major risk factor that contributes to the development of degenerative complications in certain patients.

Background: Vitamin B6 may influence colorectal carcinogenesis through its role in one-carbon metabolism related DNA synthesis and methylation. However, observational studies have been inconclusive and no studies have investigated when in the natural history vitamin B6 intake may prevent colorectal cancer. Method: We followed 86,440 women in the Nurses' Health Study and 44,410 men in the Health Professionals Follow-up Study for up to 28 years. We assessed vitamin B6 intake every 4 years using validated food frequency questionnaires. We evaluated whether higher vitamin B6 intake in the remote past is strongly associated with a lower risk of colorectal cancer than intake in the recent past. Cox proportional hazards regression models were used to estimate multivariable relative risks (MV RRs, 95%CIs). Results: Comparing top with bottom quintiles of total vitamin B6 intake, the mean plasma pyridoxal 5–phosphate (PLP, the active form of vitamin B6) levels were 98.3 pmol/mL and 38.9 pmol/mL in women and were 183.2 pmol/mL and 66.0 pmol/mL in men. Total vitamin B6 intake was significantly associated with an approximately 20–30% lower risk of colorectal cancer in age-adjusted results but these significant associations became attenuated and non-significant after adjustment for other colorectal cancer risk factors. Compared extreme quintiles of cumulative intake of total vitamin B6, the MV RRs (95%CIs) for colorectal cancer were 0.98 (0.80, 1.22; P trend = 0.79) in women and 0.98 (0.76, 1.26; P trend = 0.60) in men. For the same comparison, the MV RRs were 0.92 (0.73, 1.16) for total vitamin B6 intake 0–4 year before diagnosis, 0.99 (0.78, 1.26) for intake 4–8 year before diagnosis, 0.93 (0.71, 1.21) for intake 8–12 year before diagnosis, and 0.93 (0.69, 1.26) for intake 12–16 years before diagnosis. The corresponding MV RRs for men were 0.85 (0.63, 1.16), 0.98 (0.70, 1.37), 0.90 (0.63, 1.28), and 1.19 (0.78, 1.83), respectively. Additionally, results did not differ by cancer sub-site, sources of vitamin B6 (food or supplement), or intake of alcohol and folate. Conclusion: Although a small effect cannot be excluded, our results do not support a strong role of vitamin B6 intake in adulthood in colorectal carcinogenesis among middle-aged U.S. health professionals.

Vitamin B6 intake and 4-pyridoxic acid excretions of 22 children were determined. Mean intake of vitamin B6 per day was 1.10 mg +/- 0.47. Mean percentage of vitamin B6 intake excreted as 4-pyridoxic acid was 48% +/- 23. Excretion of 4-pyridoxic acid was significantly correlated to vitamin B6 intake but not to vitamin B6/protein ratios or vitamin B6/kilocalorie levels. Excretions of 4-pyridoxic acid equal to or below 0.15 mg appeared to be indicative of poor vitamin B6 intake for the children which was similar to the excretions found by others for depleted adults.

In order to study the influence of varying vitamin B6 intake levels on the reproductive performance and the vitamin B6 status of fetuses and reproductive organs, 30 pregnant rats

SummaryUpon the basis of the data presented, it is concluded that desoxypyridoxine exerts its inhibiting effect by being first converted into desoxypyridoxine phosphate which then competes with pyridoxal phosphate for the apoenzyme. This conclusion offers an explanation for the observation that in the animal, desoxypyridoxine exerts its antagonistic effect primarily under conditions of restricted vitamin B6 intake.

The influence of the level of vitamin B6 intake on the content of the vitamin in milk was studied in 19 healthy subjects whose stages of lactation ranged from 3 weeks to 30 months. Total vitamin B6 intakes, including extra-dietary sources of the vitamin, ranged from 1.3 to 12.5 mg per day with six subjects consuming less than the recommended allowance of 2.5 mg per day (RDA, 1974). Subjects consuming less than 2.5 mg of vitamin B6 per day had significantly less vitamin B6/liter milk (129 mug) than groups consuming 2.5 to 5.0 or greater than 5.0 mg per day (239 and 314 mug, respectively). Among subjects consuming greater than 2.5 mg of vitamin per day the stage of lactation did not influence the levels of protein or vitamin B6 in milk. Vitamin B6 intakes two to five times the recommended allowance did not significantly elevate the level of the vitamin in milk compared to values for subjects whose intakes approximated the allowance. The vitamin B6/protein ratio in milk of subjects consuming less than 2.5 mg vitamin B6 per day was 13 mug/g and was significantly lower than that observed for the other two groups (23 and 28 mug/g). Daily and weekly variations of the vitamin B6 and protein content in milk of individuals were small. However, marked diurnal variations in the vitamin B6 content were found in milk of individuals taking daily supplements of the vitamin with peak levels occurring in the afternoon 3 to 5 hr after supplements were taken in the morning.

Plasma pyridoxal phosphate concentrations were measured in 178 hospitalised neonates. A reference interval for neonates less than 7 day old, of 25 to 78 nmol/l has been established. Vitamin B6 intakes did not correlate well with plasma pyridoxal concentrations despite 26 neonates receiving less than the Recommended Allowance (0.3 mg/d) and 19 receiving amounts below which convulsions have been associated (0.1 mg/d). Ten percent of those infants fed breast milk had plasma pyridoxal phosphate levels below the reference interval compared with only 4% of those fed milk formulae. Breast milk from mothers with babies less than 14 days old had a total vitamin B6 contents reference interval of 5 to 40 micrograms/l. Twenty percent of breast milk samples had virtually no vitamin B6 detected.

Vitamin B6 is critical to normal development; however, the requirement for adequate nutriture of the human infant is based on limited experimental data. In this study vitamin B6 intakes of breast-fed (BF) and formula-fed (FF), healthy, term infants were related to levels of pyridoxal phosphate (PLP) in their plasma at 1, 2, 4, and 6 mo of age. Mothers of BF infants were supplemented with either 2.5 or 15.0 mg pyridoxine . hydrochloride (PN . HCl)/d. Growth was similar for FF and BF infants and was within normal ranges over the 6 mo period. Plasma PLP in cord blood was similar in BF and FF infants; however, at 1-5 d of age and at each subsequent age studied, levels of plasma PLP were significantly higher in FF infants than in BF. Lowest PLP values were for BF infants of mothers who received 2.5 mg PN . HCl/d. Mean plasma PLP decreased with age and was not correlated to vitamin B6 intakes except at 1 mo of age. At this age, vitamin B6 intake of BF infants whose mothers received 2.5 mg PN . HCl/d was only 0.1 mg B6/d. The consequences of this are uncertain; however, plasma PLP levels of the infants were low and reflected their intakes of vitamin B6.