Search

As the number of people with diabetes in the United States continues to rise, so does awareness for the role of nutrition counseling to prevent and treat this condition. Lifestyle changes to prevent chronic diseases are being promoted by many professional organizations. For adults, children, and adolescents with diabetes or at risk to develop diabetes, there is a positive role for moderate nutrition changes and regular physical activity.

After more than 25 years of credentialing dietetic professionals, the Commission on Dietetic Registration is revising the format for logging continuing professional education. As of 2001, the new system will be phased in over 5 years. Each registered dietetic professional will now plan a course of continuing education to meet personal and professional growth needs. This is a very exciting process and one that has many asking questions of "why, how, when, and where." This article is designed to put a perspective on the new process.

The amino acid l-arginine is the precursor of nitric oxide (NO), a powerful vasodilator with antiplatelet properties. The availability of l-arginine has been suggested to be a rate-limiting factor in the production of NO in conditions such as hypercholesterolemia. It was speculated that fluctuations in plasma concentrations of l-arginine during the day may be dependent upon dietary intake of the amino acid, or other variables, and might modify the elaboration of endogenous NO. Over a 24-h period, the plasma concentrations of l-arginine and NO-related compounds (NOx) were measured during an l-arginine and nitrate/nitrite-free diet (diet A) or a nitrate/nitrite-free diet with a fixed amount of l-arginine intake (3.8 g/d) (diet B) in eight healthy volunteers during a 2-day crossover study. Subjects were randomly selected to begin with diet A or diet B and consumed the other diet on the second day. During diet A, plasma l-arginine decreased significantly from 09.00 to 16.00 (21.4 ± 2.0 to 11.9 ± 1.1 mg/ml), rose slightly in the evening (to 16.6 ± 1.7mg/ml) and gradually increased during the night. During diet B, plasma larginine showed a peak after each meal (approximately 23 mg/ml). Plasma NOx concentrations measured by chemiluminescence did not show any circadian variation on either diet. Plasma l-arginine concentrations change during the day and are influenced by dietary intake. Importantly, plasma NOx do not seem to vary with this pattern in healthy individuals.

Abstract We examined the relation between insulin resistance, plasma glucose and insulin responses to meals, lipoprotein lipase (LPL) activity, and postprandial lipemia in a population of 37 healthy nondiabetic individuals. Plasma glucose and insulin concentrations were determined at frequent intervals from 8 am through midnight (breakfast at 8 am and lunch at noon); resistance to insulin-mediated glucose disposal was determined by measuring the steady-state plasma glucose (SSPG) concentration at the end of a 180-minute infusion of glucose, insulin, and somatostatin; LPL activity was quantified in postheparin plasma; and postprandial concentrations of triglyceride (TG)-rich lipoproteins were assessed by measuring the TG and retinyl palmitate content in plasma and the Svedberg flotation index (S f ) >400 and S f 20 to 400 lipoprotein fractions. Significant simple correlation coefficients were found between various estimates of postprandial lipemia and SSPG ( r =.38 to .68), daylong insulin response ( r =.37 to .58), daylong glucose response ( r =.10 to .39), and LPL activity ( r =−.08 to −.58). However, when multiple regression analysis was performed, only SSPG remained independently associated with both postprandial TG and retinyl palmitate concentrations. These data provide evidence that insulin resistance plays an important role in regulating the postprandial concentration of TG-rich lipoproteins, including those of intestinal origin.

The effect of dietary composition on concentrations of postprandial lipoproteins was studied in eight sulfonylurea-treated patients with noninsulin dependent diabetes mellitus. Two diets were consumed by each patient for 2 weeks in random order, one contained (as percent of total calories) 15% protein, 40% fat, and 45% carbohydrate (CHO), whereas the other consisted of 15% protein, 25% fat, and 60% CHO. At the end of each dietary period, patients were given Vitamin A (60,000 U/m2) with their noon meal, and the concentration of triglyceride (TG) and retinyl esters in plasma and two lipoprotein fractions (Sf400 and Sf 20-400) determined over the next 12 h. The results indicated that both postprandial TG and retinyl ester concentrations were higher in plasma (Sf400, and Sf 20-400 lipoproteins), when patients ate the 25% fat/60% CHO diet. Thus, replacing saturated fat with CHO accentuates the magnitude of postprandial lipemia. Since TG-rich lipoproteins may be atherogenic, appropriate dietary advice for patients with type 2 diabetes may deserve reappraisal.

In this paper we have compared the postprandial increase in triglyceride (TG) rich lipoproteins of intestinal origin in 10 patients with noninsulin-dependent diabetes mellitus (NIDDM) and 10 subjects with normal glucose tolerance. The two groups were matched for age, sex distribution, body mass index, and plasma TG concentration. Breakfast was consumed at 0800 h and lunch at 1200 h, at which time vitamin A was also administered. Blood was sampled frequently from 1200 h to 2400 h, and measurements made of glucose, insulin, and TG concentrations. Furthermore, the retinyl palmitate (RP) content of plasma, the Sf400 lipoprotein fraction, and the Sf 20-400 lipoprotein fraction was also determined, and differences compared by two-way analysis of variance. Fasting and postprandial (from 1200 h to 2400 h) TG concentrations in the plasma and the two lipoprotein fractions were not significantly different in normal subjects and patients with NIDDM. In addition, the postprandial RP concentration of the two groups was not different in the chylomicron containing Sf400 lipoprotein fraction. However, the postprandial Sf 20-400 RP concentration was significantly higher (P0.001) in patients with NIDDM, estimated as hourly values over time, peak value, or total integrated response area. Significant correlation coefficients (r = 0.60-0.75, P0.080.02) were seen in patients with NIDDM between the total integrated insulin response and both the TG and RP responses in the Sf400 and Sf 20-400 fractions. In addition, fasting high density lipoprotein-cholesterol concentration in patients with NIDDM was significantly correlated with the postprandial TG response in the Sf400 (r = -0.64, P0.05) and the Sf 20-400 (r = -0.68, P0.05) lipoprotein fractions. In summary, the postprandial RP concentration in the Sf 20-400 lipoprotein fraction was higher than normal in patients with NIDDM. In addition, associations have been defined in patients with NIDDM between postprandial insulin response, fasting TG and high density lipoprotein-cholesterol concentrations, and magnitude of postprandial increase in TG-rich lipoproteins of intestinal origin.

A classification of carbohydrate-containing foods based on their glycemic response to 50-g carbohydrate portions has recently been developed. The relative glycemic potency of many of these carbohydrate-containing foods have been compared, and these data have been published in the form of a glycemic index. It has been suggested that meals containing low glycemic index foods will result in a lower postprandial glucose response than meals with a higher glycemic index. However, whether or not these data will lead to a clinically useful reduction in postprandial hyperglycemia in individuals with carbohydrate intolerance remains controversial. In this review, we will try to delineate why we believe that the glycemic index, as currently developed, may be a specious issue. In addition, we will briefly discuss a number of factors that may explain the apparent discrepancy in viewpoints on this issue.Key words: glycemic index, noninsulin-dependent diabetes mellitus, glycemic response, dietary carbohydrate.

Nutritional status was monitored in two groups of patients infected with human immunodeficiency virus (HIV) for up to 16 months. Twenty-six subjects were recruited from patients enrolled in acquired immunodeficiency syndrome treatment protocols in the early stages of the disease. Body weight, percent body fat, serum albumin, total protein concentration, hemoglobin, hematocrit, and total lymphocyte count were monitored monthly. Four-day food intake records were kept every 4 months. In the 19 patients followed for 16 months (Group 1), a significant (p

Eighteen residents with non-insulin-dependent diabetes mellitus (NIDDM) from two skilled nursing facilities were monitored for glycemic control on diabetic and regular diets provided by the institution. Weekly fasting plasma glucose and 1-d dietary intake were followed for 16 wk: 4 wk on diabetic diets before and after an 8-wk regular-diet period. All residents were in good glycemic control (fasting plasma glucose 7.0 +/- 0.6 mmol/L) at entry into the study. During the regular-diet period, fasting plasma glucose increased an average of 0.6 mmol/L for all residents. Caloric intake increased during the regular-diet period although body weight did not change significantly. In both study periods nutrient intake of the residents met or exceeded the Recommended Dietary Allowances for the age group. These results indicate that the short-term substitution of regular for diabetic diets did not result in gross deterioration of glycemic control in patients with NIDDM confined to chronic-care facilities.

Obesity has reached what some scientists see as epidemic proportions. Clearly, a rethinking of the medical nutritional therapeutic approach is needed. Treatment programs must include a variety of health professionals to facilitate the lifestyle changes needed to treat this condition. There is a role in obesity management for registered dietitians, behaviorists, physicians, exercise physiologists, and geneticists. A chronic disease treatment model is being proposed. Are dietitians ready for the challenge? J Am Diet Assoc. 1998;98(suppl 2):S6–S8 .

Background A variety of food combinations can be used to meet national U.S. guidelines for obtaining 30% of energy or less from total fat and 10% of energy or less from saturated fat. Objective To contrast plasma lipid responses to 2 low-fat diet patterns. Design Randomized clinical trial. Setting 4-week outpatient feeding study with weight held constant. Participants 120 adults 30 to 65 years of age with prestudy low-density lipoprotein (LDL) cholesterol concentrations of 3.3 to 4.8 mmol/L (130 to 190 mg/dL), body mass index less than 31 kg/m2, estimated dietary saturated fat at least 10% of calories, and otherwise general good health. Measurements Plasma lipid levels. Intervention Two diets, the Low-Fat diet and the Low-Fat Plus diet, designed to be identical in total fat, saturated fat, protein, carbohydrate, and cholesterol content, consistent with former American Heart Association Step I guidelines. The Low-Fat diet was relatively typical of a low-fat U.S. diet. The Low-Fat Plus diet incorporated considerably more vegetables, legumes, and whole grains, consistent with the 2000 American Heart Association revised guidelines. Results Four-week changes in the Low-Fat and Low-Fat Plus groups were -0.24 mmol/L (-9.2 mg/dL) versus -0.46 mmol/L (-17.6 mg/dL) for total cholesterol (P = 0.01) and -0.18 mmol/L (-7.0 mg/dL) versus -0.36 mmol/L (-13.8 mg/dL) for LDL cholesterol (P = 0.02); between-group differences were -0.22 mmol/L (-9 mg/dL) (95% CI, -0.05 to -0.39 mmol/L [-2 to -15 mg/dL]) and -0.18 mmol/L (-7 mg/dL) (CI, -0.04 to -0.32 mmol/L [-2 to -12 mg/dL]) for total and LDL cholesterol, respectively. The 2 diet groups did not differ significantly in high-density lipoprotein cholesterol and triglyceride levels. Limitations 4-week duration. Conclusions Previous national dietary guidelines primarily emphasized avoiding saturated fat and cholesterol; as a result, the guidelines probably underestimated the potential LDL cholesterol-lowering effect of diet. In this study, emphasis on including nutrient-dense plant-based foods, consistent with recently revised national guidelines, increased the total and LDL cholesterol-lowering effect of a low-fat diet.

Insulin resistance and type 2 diabetes are complex conditions which carry with them major health risk of increased morbidity and mortality. Insulin resistance is a genetic predisposition in which the normal actions of insulin are impaired. Only in the face of environmental stress of such factors as decreased physical activity or excess body weight, this genetic trait presents as an abnormal condition called the metabolic syndrome, or insulin resistance syndrome, or syndrome X. The insulin resistance syndrome or metabolic syndrome is a clustering of cardiovascular risk factors, namely, glucose intolerance, dyslipidemia (elevated plasma triglyceride [TG] concentration, decreased high-density lipoprotein cholesterol [HDL-C]), abdominal obesity, hypertension, and elevated coagulation factors. Prevalence differed little among men (24%) and women (23.4%). Women with insulin resistance are prone to develop gestational diabetes during pregnancy and both men and women who have insulin resistance can progress to type 2 diabetes primarily prompted by age, increased body weight, and decreased physical activity.

Insulin resistance is an increasingly common metabolic abnormality characterized by an impaired physiological response to insulin. The constellation of insulin resistance and several other metabolic and vascular disorders is known as the insulin resistance syndrome. The characteristic features of the insulin resistance syndrome include central obesity, hypertension, dyslipidemia, glucose intolerance and specific abnormalities of both endothelial cell and vascular function. Although insulin resistance can arise in response to aging, obesity and inactivity, there is a clear genetic component. Insulin resistance is not generally attributable to a single genetic defect. Indeed, it is very likely to be a polygenic disorder in most individuals. A genetic predisposition is suggested to be the demonstration of increased insulin resistance in first-degree relatives of patients with diabetes and by a high incidence of insulin resistance in specific populations. Epidemiological data have demonstrated a strong association between a clustering of specific factors and the risk of cardiovascular disease. The diagnosis of the insulin resistance syndrome remains a significant clinical challenge. At present, clinicians are faced with establishing a clinical diagnosis despite varying definitions of the disorder and controversy regarding how many components presage clinical events. A proposed approach to the management of patients with the insulin resistance syndrome is discussed.

A wealth of nutrition information has been published during the past decade on the healthful nature of nuts. As nut consumption increases, cardiovascular disease risk decreases. This cardioprotective effect of nut consumption is beyond what would be predicted from the fatty acid profile alone. Nuts are a rich source of many other nutrients and bioactive compounds, similar to other whole-plant foods, such as fruits and vegetables. Additional studies during the next decade will delineate additional healthful nutrients of these foods.

Diabetes mellitus is a group of metabolic disorders characterized by hyperglycemia resulting from defects in insulin secretion, insulin action, or both. The hyperglycemia of diabetes increases the risk of a variety of complications including cardiovascular disease, stroke, visual impairment, and blindness, nephropathy leading to renal failure, and neuropathy. Duration and degree of obesity can affect insulin secretion rates. Reduced energy intake and moderate weight loss improve insulin sensitivity and lower blood glucose levels in type 2 patients. Nutrition therapy is an important part of the overall management of diabetes. Current nutrition recommendations to achieve and maintain glucose, lipid, and blood pressure goals are simple to state, but difficult to initiate and even more difficult to maintain. In this chapter, nutrient components of the diet are discussed in relation to the impact they have on diabetes treatment. The entire disease management process is enhanced due to the advances in oral medications for glucose and lipid control. In addition, with an increased focus on near-normal glycemic control in this population, all health care team members are more closely involved in assisting the patients with disease management.

Diabetes mellitus is a serious and fairly common metabolic disorder that affects carbohydrate, protein and fat metabolism. Indications for nutritional support are no different for patients with diabetes than in any other patient group. The setting may be recovery from surgery or trauma and transition to solid food is anticipated, or, as a result of permanent injury or stroke, enteral feeding may be the permanent manner of nutrition delivery. Attention must be given to the selection of a macronutrient intake that will optimize blood glucose and lipid control. It is vital that blood glucose concentration be carefully monitored and that over- and underfeeding be avoided.

In the United States, the notion that low-fat, high-carbohydrate diets are essential for health has grown into an obsession, driven largely by an effort to reduce heart disease and, more recently, certain types of cancer. We know that saturated fatty acids are more closely associated with risk factors for heart disease than are unsaturated fatty acids. Many people believe that plant-based diets are healthy because they are low in fat. However, plant-based diets are not necessarily low-fat. In true plant-based diets, unsaturated fatty acids predominate, whereas saturated fatty acids come largely from animal sources such as dairy products and eggs. Plant-based diets include foods that contain fats, such as nuts and seeds and oils from grains and seeds. The fats in these foods are not associated with increased risk for heart disease. In addition, for people with insulin resistance, higher-fat diets protect against the heart disease risk factors of low HDL-cholesterol concentration, hypertriglyceridemia, hyperglycemia, and hyperinsulinemia. Because humans can synthesize fat from dietary carbohydrate, and because our adipose stores and circulating fatty acids reflect dietary intake, scientists understand the relations between the amounts and types of dietary fats and the types of fats found in body fat depots. Consuming dietary fats that are not associated with increased risk of disease can be a part of a healthful diet.

The relation between the self-reported intake of various dietary constituents and insulin-mediated glucose disposal was evaluated in 52 healthy volunteers. Insulin-mediated glucose uptake was independently associated with degree of obesity (inversely) and estimates of level of physical activity (directly). An independent relation between increased intake of vitamin A and insulin action was shown, ie, the greater the intake of vitamin A, the more effective was insulin in stimulating glucose disposal. However, there was no independent relation noted between insulin-mediated glucose disposal and estimates of the intake of carbohydrate, protein, amount or kind of fat, fiber, or vitamins C and E. Furthermore, the 20 individuals with estimates of vitamin A consumption > 10 000 IU/d had significantly lower plasma glucose (P < 0.01) and insulin (P < 0.05) responses to oral glucose, and insulin-mediated glucose disposal values that were higher (P < 0.005) than those of the 20 individuals whose estimated vitamin A intake was < 8000 IU/d. These results suggest that vitamin A intake, but not intakes of vitamin C and E, fiber, fat, or carbohydrate is associated with enhanced insulin-mediated glucose disposal.

Objective To identify older adults with poor nutritional status among the independent-living elderly applying for meals-on-wheels, and to compare how a self-assessment tool and more traditional criteria identify nutritional risk. Design Descriptive study. Subjects/setting Meals-on-wheels applicants (n=230) between 60 and 90 years of age (mean age=77.4±7 years) who were free from terminal illness. Nutrition assessment data were collected in the home of each participant. Main outcome measures Risk assessment for poor nutritional status was determined using anthropometric, dietary, and laboratory data and with a Nutrition Screening Initiative (NSI) self-assessment tool — the "DETERMINE Your Nutritional Health" checklist. Statistical analyses Differences were assessed using Student's t test for unpaired data. Results Seventy-four percent of study participants were found to be at risk for poor nutritional status according to the study criteria, and 98% were at risk for poor nutritional status according to the NSI self-assessment tool. Conclusions The majority of the applicants for meals-on-wheels were at risk for poor nutritional status. Thus, many independent-living older adults may need additional nutrition assessment and intervention to remain independent and in good nutritional status. J Am Diet Assoc. 1996; 96:570-573.

It has been shown that addition of fructose to an oral fat load results in higher postprandial concentrations of triglyceride. The present study, performed in 11 healthy volunteers, was initiated to see whether the effect of fructose on fat-induced lipemia also involved changes in postprandial concentrations of triglyceride-rich lipoproteins of intestinal origin. Vitamin A was used to label intestinal lipoproteins, and the retinyl palmitate concentrations were determined in plasma and in the Sf > 400 and Sf 20-400 lipoprotein fractions (Sf denotes the Svedberg flotation index). Addition of fructose (50 g) to a standard (40-g oral) fat load resulted in higher postprandial concentrations of triglyceride and retinyl palmitate in plasma and the Sf > 400 lipoprotein fraction (P < 0.001, analysis of variance), and the higher the fasting plasma triglyceride concentration, the greater the magnitude of the fructose effect (r = 0.83, P < 0.002). These data show that triglyceride-rich lipoproteins of intestinal origin play a role in the fructose-induced accentuation of postprandial lipemia.

This study compared use of unconventional remedies in two groups of HIV-positive men (N = 63). Employing a multiple-choice questionnaire, the authors assessed the use of and attitudes toward unconventional remedies among two groups of white HIV-positive men similar in age, socioeconomic status, and severity of illness, all of whom lived in Northern California. One group (n = 36) participated in AIDS clinical trial protocols; the other group (n = 27) received health care at a community health center. Participants at all sites expressed positive views upon increasing unconventional remedies. Individuals enrolled in the clinical trial protocols for investigational drugs used unconventional remedies significantly less than the community health center participants, who were enrolled in an open clinical trial of hypericin, an unproven remedy.

OBJECTIVE To understand why low-fat high-carbohydrate (CHO) diets lead to higher fasting and postprandial concentrations of triglyceride (TG)-rich lipoproteins in patients with non-insulin-dependent diabetes mellitus (NIDDM). RESEARCH DESIGN AND METHODS Patients with NIDDM were placed randomly on diets containing either 55% CHO, 30% fat, and 15% protein or 40% CHO, 45% fat, and 15% protein for 6 weeks, followed by crossover to the other diet. Test meals at the end of each diet period were consumed at 8:00 A.M. and 12:00 P.M. (noon) and contained 20 and 40% of daily calories, respectively. Vitamin A was also given at noon, and TG-rich lipoproteins of intestinal origin were identified by the presence of vitamin A esters. Frequent measurements were made throughout the 24-h study period of plasma glucose, insulin, and TG concentrations. Plasma samples obtained from 12:00 P.M. (noon) until 12 A.M. (midnight) were subjected to ultracentrifugation, and measurements were made of TG and vitamin A ester concentrations in plasma and in both the Svedberg flotation constant (Sf) >400 (chylomicron) and Sf 20-400 (chylomicron remnant) lipoprotein fractions. In addition, very-low-density lipoprotein (VLDL)-TG turnover rate was estimated by following the decay of [3H]VLDL-TG. Finally, postheparin lipoprotein lipase and hepatic lipase activities were measured at the end of each dietary period. RESULTS Mean ± SE hourly concentrations of glucose (8.0 ± 0.8 vs. 7.5 ± 0.7 mmol/1), insulin (184 ± 26 vs. 158 ± 19 pmol/1), and TG (2.8 ± 0.2 vs. 2.1 ± 0.2 mmol/1) were higher (P < 0.05-0.001) after the 55% CHO diet. The 55% CHO diet also led to an increase (P < 0.05-0.01) in the mean ± SE hourly concentrations of vitamin A esters in plasma (2.3 ± 0.3 vs. 1.6 ±0.1 μmol/l) and in both the chylomicron (2.0 ± 0.3 vs. 1.4 ±0.1 μmol/l) and chylomicron remnant fractions (0.36 ± 0.04 vs. 0.14 ± 0.03 μmol;/l). In addition, the VLDL-TG production rate was higher (17.2 ± 1.4 vs. 12.8 ± 1.0 mg · kg−1 · h−1, P < 0.003) and the VLDL-TG fractional catabolic rate lower (0.22 ± 0.02 to 0.28 ± 0.02 l/h, P < 0.005) after the 55% CHO diet. Finally, there was an increase in lipoprotein lipase activity (7.0 ± 0.8 to 8.1 ± 0.7 μmol free fatty acids released · ml−1 · h−1, P < 0.02) in response to the CHO-enriched diet. CONCLUSIONS A low-fat high-CHO diet in patients with NIDDM led to 1) higher day-long plasma glucose, insulin, and TG concentrations; 2) postprandial accumulation of TG-rich lipoproteins of intestinal origin; 3) increased production of VLDL-TG; and 4) increased postheparin lipoprotein lipase activity. These data provide a mechanism for the hypertriglycer-idemic effect of CHO-enriched diets in patients with NIDDM and demonstrate that multiple risk factors for coronary heart disease are accentuated when these individuals consume diets recommended to reduce this risk.