Low Cholesterol Intake Research Articles

Polymorphisms of the genes encoding apoproteins A-I, B, C-III, and E and LDL receptor, and cholesterol and LDL metabolism during increased cholesterol intake. Common alleles of the apoprotein E gene show the greatest regulatory impact.

Genetic and dietary factors regulate serum cholesterol level, but detailed investigations into their interactions have not been established. We assessed the effects of apoprotein (apo) E phenotype and polymorphic alleles of the apo A-I, apo B, apo C-III, and LDL receptor genes, separately and together, on regulation of serum LDL cholesterol level. The study group consisted of 29 middle-aged men, and cholesterol absorption, bile acid, and cholesterol synthesis and LDL apo B kinetics were studied in these men during low- and high-cholesterol diets. The six apo B alleles were identified on the basis of Xba I, EcoRI, and Msp I restriction fragment length polymorphism (RFLP), the apo A-I alleles with the Msp I RFLP, and the apo C-III and LDL receptor alleles corresponded to the Sst I and PvuII RPLPs of these genes, respectively. During low cholesterol intake, LDL cholesterol levels were similar in all of the genetic groups except for men with apo E2 phenotype. They had significantly (P < .05) lower levels of LDL apo B and cholesterol than men without the epsilon 2 allele. The low values were caused by a significantly higher removal of LDL apo B (apo E2, 0.453 +/- 0.03 versus apo E3, 0.312 +/- 0.01 pools per day, P < .05). High cholesterol intake increased LDL cholesterol levels in all genetic categories except in the apo E2 phenotype irrespective of the combinations with other polymorphisms. Carriers of the apo B R+ allele (EcoRI site present) presented with the most prominent LDL cholesterol rise (from 2.71 +/- 0.14 to 3.37 +/- 0.29 mmol/L). In multiple stepwise regression analysis, apo B EcoRI RFLP and apo E phenotypes were the only variables that explained the variability of high cholesterol intake-induced change in LDL cholesterol levels. In summary, in any genetic combination, individuals with the epsilon 2 allele had the lowest LDL cholesterol values and were nonresponders to dietary cholesterol, whereas subjects with the apo B R+ allele had marked LDL elevations, especially in combination with the epsilon 4.

The 'diet heart' hypothesis in secondary prevention of coronary heart disease.

From this detailed analysis of the main dietary trials conducted over the last 30 years in the secondary prevention of coronary heart disease, it can be said that the older trials were conducted on low risk patients and used high fat diets (about 40% of energy as lipids), comprising low saturated fat and cholesterol intake but very high (15 to 20% of energy) polyunsaturated fat intake, particularly from the omega-6 fatty acid family. These experimental diets were designed to reduce blood cholesterol and failed to improve prognosis. By contrast, recent trials were not primarily designed to reduce cholesterol, were conducted in medium- and high-risk patients and used low fat diets supplemented by omega-3 fatty acids from various sources. In two of these trials, the consumption of natural antioxidants, oligoelements and vegetable proteins was increased. Recurrence rate was reduced in the range of 30 to 70%. One conclusion from these well-conducted recent experiments on more than 3000 patients is that new and more specific dietary recommendations are clearly warranted in secondary prevention of coronary heart disease. They should be more specific and more clearly defined and therefore different from those generally provided in the U.S.A. and Europe at present. In a recent Consensus Panel statement, authors wrote less than one line to describe a cardioprotective diet in patients with coronary heart disease, summarized as < or = 30% fat, < 7% saturated fat, < 200 mg.day-1 cholesterol. This is both too much (too restrictive to hope that white European and American patients will adhere in the long-term) and insufficient because dietary counselling cannot be restricted to three factors. Ulbricht and Southgate recently emphasized that the relationship between diet and coronary heart disease is more complex than the current cholesterol hypothesis. They identified at least seven major dietary factors, including fibres, although the evidence of an effect on coronary heart disease is weak. However, they did not mention vegetable and fish proteins which are rich in arginine and L-glutamine, major regulators of cardiovascular function. Thus, new dietary advice should include: reduce intake of total (not more than 30% of energy) and saturated (less than 10%) fats maintain intake at least minimally, of the essential omega-6 fatty acids augment consumption of oleic acid and moderately increase consumption of omega-3 fatty acids augment intake of natural antioxidants and oligo-elements maintain sufficient intake of vegetable proteins As conceptualized in the 'Mediterranean' and 'Asian-vegetarian' types of diet, it is very important that a healthy diet should be thought of as a whole rather than as a recitation of good and bad components. Although these protective dietary modifications should probably all be used in each patient to obtain maximal efficacy, these scientifically quantitated principles should be adapted to the culture, ethnic origin and 'image of the world' of each patient in order to create an environment favourable to the perception of positive associations between various foods and healthy habits.

A School-Based Cardiovascular Exercise and Nutrition Program With Parent Participation: An Evaluation Study

This study examined the efficacy of a school-based exercise and nutrition program with a parent component. Second-grade and fourth-grade classrooms were assigned randomly to a treatment and a control group. The school-based treatment program focused on decreasing fat and cholesterol intake and increasingly physical activity with a parent educational component. Children in the treatment group scored significantly higher and demonstrated greater improvement on fitness/nutrition knowledge and on vegetable and fruit servings. Parents who participated in the intervention increased their scores on the fitness/nutrition knowledge test. There also was a significant association between degree of family involvement, higher grain servings, and lower cholesterol intake. The results within the study limitations were interpreted to suggest that the program was primarily effective in enhancing knowledge changes for both children and their parents.

Increased messenger RNA levels for low-density lipoprotein receptor and 3-hydroxy-3-methylglutaryl coenzyme a reductase in rat liver after long-term ethanol ingestion

Because long-term alcohol intake leads to severe alterations of cholesterol metabolism resulting in both elevated serum cholesterol levels and increased hepatic concentrations of cholesterol esters, we investigated the effect of long-term ethanol consumption on the hepatic messenger RNA (mRNA) content of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase and low-density lipoprotein receptor, two major regulatory factors in cholesterol metabolism, and of apoprotein E. Twenty-four male Sprague-Dawley rats were pair-fed nutritionally adequate liquid diets containing 36% of total calories as either ethanol or isocaloric carbohydrates for 3 wk. In addition, the lipid content of the diets was varied, resulting in 35%, 17.5%, and 8.8% of total calories corresponding to a daily intake of cholesterol of between 1.2 and 6.3 mg/kg body wt. Although increasing dietary cholesterol intake resulted in a significant decrease of hepatic mRNA for low-density lipoprotein receptor and HMG-CoA reductase (p < 0.05), long-term ethanol consumption led to a significant increase of the mRNA for both proteins (p < 0.01), and this increase was predominantly obvious in animals fed a low-cholesterol diet. In contrast, mRNA content of apoprotein E was found to be significantly lower in livers from rats fed ethanol for a prolonged period of time as compared with controls (p < 0.01), and this effect was found to be still present, although less pronounced, after low cholesterol intake.(ABSTRACT TRUNCATED AT 250 WORDS)

Cholesterol absorption and excretion in ileostomy subjects on high- and low-dietary-cholesterol intakes

Six healthy ileostomy subjects were given [3H]cholesterol and [14C]beta-sitosterol in a single meal together with two controlled diets containing 150 or 450 mg cholesterol/d. Each diet was eaten for 3 d. Cholesterol absorption and excretion of cholesterol, bile acids, fat, energy, and nitrogen were analyzed. Fractional cholesterol absorption increased from 44 +/- 2.6% (mean +/- SE) to 61 +/- 3.4% (P < 0.05), but absolute cholesterol absorption decreased from 191 +/- 11 to 94 +/- 9 mg/d (P < 0.05) on low cholesterol intake compared with high cholesterol intake. Weight of ileostomy effluent, or excretion of energy, nitrogen, fat, and bile acids did not differ between periods. Endogenous cholesterol excretion remained unchanged whereas net cholesterol excretion (output minus intake) was 37% higher (P < 0.05) on low compared with high cholesterol intake.

Estimates of nutrient intake from a food frequency questionnaire: The 1987 National Health interview Survey

Nutrient intake data are reported from a 60-item food frequency questionnaire administered in the 1987 National Health Interview Survey to a representative sample of US adults 18 to 99 years of age (n = 22,080). These data provide for the first time an estimate of the distribution of usual nutrient intakes in a national probability sample. For several nutrients, 10% to 25% of respondents may habitually consume substantially less than the Recommended Dietary Allowance, despite apparently adequate group means. Hispanics reported higher energy and carbohydrate intakes and a lower percentage of energy from fat than blacks or whites (35.6%, 38.4%, and 38.7% of energy from fat for Hispanics, blacks, and whites, respectively.) Whites had lower cholesterol intake than the other two groups, and blacks had a higher intake of sweets. Alcohol intake was lower among women and persons older than 65 years, but no other differences in alcohol intake emerged. Use of adjustment factors improved nutrient intake estimates from this shortened questionnaire to levels similar to those obtained from other national dietary surveys. The nutrient intake data from this research can be used to compare demographic subgroups and to describe the mean and distribution of nutrient intake. Furthermore, this research provides national reference data to investigators who use this or related questionnaires in nutrition research.

Exclusive Breast-Feeding and Weaning: Effect on Serum Cholesterol and Lipoprotein Concentrations in Infants During the First Year of Life

The total serum cholesterol concentration of infants was investigated at birth (n = 193) and at the ages of 2 (n = 192), 4 (n = 192), 6 (n = 190), 9 (n = 188), and 12 months (n = 196). Concentrations of cholesterol--very-low-density lipoprotein (VLDL), low-density lipoprotein (LDL), high-density lipoprotein-2 (HDL2), HDL3--and apoprotein B were analyzed in 36 infants at 2, 6, 9, and 12 months of age. Serum cholesterol concentration rose significantly more slowly in the weaned infants compared with exclusively breast-fed infants. The mean difference in total serum cholesterol value between the exclusively breast-fed and weaned infants was largest at ages 2 (0.9 mmol/L, P less than .001), 4 (0.6 mmol/L, P less than .01), and 6 months (0.5 mmol/L, P less than .01). The LDL cholesterol concentration was lower in weaned infants compared with exclusively breast-fed infants at age 2 and 6 months; the mean difference in LDL cholesterol value was 0.9 mmol/L at age 2 months (P less than .001) and 0.7 mmol/L at age 6 months (P less than .025). Also, the apoprotein B concentration was lower in weaned infants; the mean difference was 24 mg/dL at age 2 months (P less than .01) and 30 mg/dL at age 6 months (P less than .05). The apoprotein B-LDL cholesterol ratio was stable and similar in both feeding groups through the year. The HDL2 cholesterol concentration was lower in the formula-fed than in breast-fed infants at 2 months of age while the VLDL and HDL3 cholesterol concentrations were independent of the diet.(ABSTRACT TRUNCATED AT 250 WORDS)

Prevalence of cardiovascular risk factors in rural and urban Costa Rica.

Coronary artery disease (CAD) is becoming more prevalent in developing countries, particularly in the urban areas, in contrast to the CAD mortality trends observed in some industrialized nations. We determined the prevalence of cardiovascular risk factors (hypertension, diabetes, smoking, obesity, total cholesterol greater than or equal to 240 mg/dl and greater than or equal to 200 less than or equal to 239 mg/dl, low density lipoprotein (LDL) cholesterol greater than or equal to 160 mg/dl and greater than 130 less than or equal to 159 mg/dl, and high density lipoprotein (HDL) cholesterol less than 35 mg/dl) in 222 men and 243 women from rural and urban areas of Puriscal, Costa Rica, using the American Cholesterol Education Program guidelines. Urban Puriscal men had a significantly (p less than 0.05) higher prevalence of borderline high-risk total cholesterol (26% versus 14%), borderline high-risk LDL cholesterol (21% versus 11%), smoking (32% versus 13%), and higher prevalence of low HDL cholesterol (34% versus 24%), hypertension (16% versus 13%), diabetes (4.5% versus 2.7%), obesity (21% versus 14%), and saturated fat intake greater than 15% of calories (14% versus 7%) than rural men from Puriscal. No significant differences between rural and urban women were found for any of the cardiovascular risk factors. Urban Puriscal residents were also more sedentary than rural Puriscal residents. These data indicate that modifiable risk factors are more prevalent in urban than in rural Puriscal, Costa Rica, particularly in men.

Black-white differences in exercise blood pressure. The Lipid Research Clinics Program Prevalence Study.

After exclusion of persons on blood pressure medication or with prevalent cardiovascular disease, we studied 83 black and 2,548 white men and 113 black and 1,519 white women 20-69 years old from the Lipid Research Clinics population sample who had performed a standardized treadmill exercise test. Resting systolic and diastolic blood pressures were similar in black and white men, but the diastolic pressure was significantly higher in black than in white women (81.4 vs 77.4 mm Hg). Body weight was higher in black than in white women, and reported physical activity was higher in black than in white men. The proportion of smokers was somewhat higher in blacks than in whites. During the treadmill exercise test with a modified Bruce protocol, mean systolic blood pressure at stage 2 was 174 mm Hg in black men and 166 mm Hg in white men (p less than 0.02), but stage 2 blood pressures did not differ between black and white women (153 and 152 mm Hg, respectively). Even after adjustments were made for levels of baseline characteristics (age, weight, resting systolic blood pressure, smoking, low density lipoprotein cholesterol, physical activity, and alcohol intake), black men responded with a 7-mm Hg higher systolic blood pressure during exercise than white men (p less than 0.01). Another new finding was a highly significant positive association between stage 2 systolic blood pressure and low density lipoprotein cholesterol in men. The findings suggest a higher systemic vascular resistance during exercise in the selected sample of black men, which is consistent with the higher incidence of hypertension in black men.

Dietary lipids and thrombosis. Relationships to atherosclerosis.

A high intake of saturated fatty acids and cholesterol is associated with a high incidence of occlusive arterial lesions involving both atherosclerosis and thrombosis. The evidence is based on epidemiological, experimental, and clinical studies. Such dietary habits increase serum low density lipoprotein cholesterol, a main risk factor for atherosclerosis. The mechanisms by which dietary saturated fatty acids are connected to arterial thrombogenesis are only partly known. Experimental and epidemiological studies also indicate an association between dietary saturated fatty acids and venous thrombosis; however, the chain of evidence lacks documentation from prospective clinical studies. When unsaturated fatty acids of the (n-9), (n-6), or (n-3) families replace saturated fatty acids in the diet, risk factors related to atherosclerosis may be reduced and the development of atherosclerosis, inhibited. This potential is related both to the reduction of saturated fatty acids and, in varying degrees, to the individual unsaturated fatty acids. The very long-chain fatty acids of the (n-3) family and probably also linoleic acid of the (n-6) family have the potential to inhibit thrombogenesis. In this respect, the effect of the individual fatty acids seems even more important. To obtain an optimal dietary lipid composition for the prevention of atherosclerosis and thrombosis, it is important to appreciate the metabolic and structural effects of the individual fatty acids. The interaction between the various dietary fatty acids and their effects on lipid biosynthesis is still only partly known. The present nutritional recommendations include a low intake of saturated fatty acids and cholesterol and a balanced content of the unsaturated fatty acids and represent a well-documented approach to the prevention of both processes.

CHD and its risk factors in the People's Republic of China

Mortality data obtained from the Health Statistics Office of the Ministry of Health, People's Republic of China (PRC), were compared to data for other countries taken from the World Health Statistics Annual. The crude death rate for coronary heart disease (CHD) in China in 1984 is estimated to be about one-tenth of that for North America and Australia. However, a high stroke to CHD ratio of about 5.0 was observed in China. The age-standardized CHD mortality rates were significantly higher for Beijing in north China than for Shanghai and Guangzhou in the south, and for urban than rural populations in all years from 1976 to 1986. Data on hospital admissions and autopsy material provide evidence for an increase in CHD incidence and prevalence in the last three to four decades. A low mean serum total cholesterol, related to a low habitual dietary intake of fat and cholesterol, is considered to be the main cause underlying low CHD mortality rates in China.

Effects of Dietary Proteins on Plasma Lipoprotein Levels in Normal Subjects

We have compared the effects of dietary soy protein and casein in diets low in cholesterol (less than 100 mg/d) and in diets enriched in cholesterol (500 mg/d) to examine whether the level of cholesterol intake affects the response of plasma lipoproteins to dietary proteins of plant and animal origin. Normal men and women consumed formula diets containing 20% of calories as soy protein or casein, 27% as fat and 53% as carbohydrate in 2 crossover studies. The dietary periods lasted for 31 days and were separated by a month-long interim period on self-chosen food. Following an initial reduction of plasma total cholesterol and low-density lipoprotein-cholesterol (LDL-C) levels on all diets, the plasma lipid and lipoprotein concentrations stabilized. On low-cholesterol diets the concentration of each of the major lipoprotein classes were similar during the soy and the casein dietary periods. On cholesterol-enriched diets, the concentration of LDL-C stabilized at a 16% lower level on soy protein than on the casein diet (p less than 0.02), while the concentration of high-density lipoprotein-cholesterol (HDL-C) was 16% higher (p less than 0.01). Since the difference in LDL-C (p less than 0.05) and in HDL-C (p less than 0.025) levels on casein and on soy protein diets were significantly greater on the high than on the low cholesterol intake, the findings indicate that the level of dietary cholesterol may determine whether plant and animal dietary proteins have similar or different effects on plasma LDL-C and HDL-C concentrations.

A low-fat diet decreases high density lipoprotein (HDL) cholesterol levels by decreasing HDL apolipoprotein transport rates.

Diets that reduce atherosclerosis risk lower levels of HDL cholesterol (HDL-C), but the significance of this is unclear. To better understand the mechanism of this phenomenon we studied the turnover of HDL apolipoproteins A-I and A-II in 13 subjects on two contrasting metabolic diets. Upon changing from high to low intake of saturated fat and cholesterol the mean HDL-C decreased 29% from 56 +/- 13 (SD) to 40 +/- 10 mg/dl, while apo A-I levels fell 23% from 139 +/- 22 to 107 +/- 22 mg/dl (both P less than 0.001). Mean apo A-II levels did not change. The fractional catabolic rate (FCR) of apo A-I increased 11% from 0.228 +/- 0.048 to 0.254 +/- 0.063 pools/d, while its absolute transport rate (TR) decreased 14% from 12.0 +/- 2.7 to 10.3 +/- 3.4 mg/kg per d (both P = 0.005). The decrease in HDL-C and apo A-I levels correlated with the decrease in apo A-I TR (r = 0.79 and 0.83, respectively; P less than 0.001), but not with the increase in apo A-I FCR (r = -0.04 and -0.02, respectively). In contrast, within each diet the HDL-C and apo A-I levels were inversely correlated with apo A-I FCR both on the high-fat (r = -0.85 and -0.77, P less than 0.001 and = 0.002, respectively) and low-fat diets (r = -0.67 and -0.48, P = 0.012 and 0.098, respectively) but not with apo A-I TR. In summary, diet-induced changes in HDL-C levels correlate with and may result from changes in apo A-I TR. In contrast, differences in HDL-C levels between people on a given diet correlate with and may result from differences in apo A-I FCR. Therefore, the mechanism of dietary effects on HDL levels differs substantially from the mechanism explaining the differences in levels between individuals on a fixed diet. In assessing coronary heart disease risk, it may be inappropriate to conclude that diet-induced decreases in HDL are equivalent to low HDL within a given diet.

The Dietary Impacts of the School Breakfast Program

AbstractThis study examines the dietary impacts of the School Breakfast Program based on twenty‐four‐hour dietary recall data collected during the 1980–81 school year. An important finding is that program availability has no significant relationship with the likelihood of eating breakfast, suggesting that a major program policy objective—to provide a breakfast to children who would not otherwise eat one—is not being achieved. Principal findings from the nutrient intake analysis are: (a) calcium intake, both at breakfast and over twenty‐four hours, is positively related to program participation; (b) participation in the program is associated with lower intakes of cholesterol, both at breakfast and over twenty‐four hours; and (c) iron intake at breakfast is negatively related to program participation.

Absorption and metabolism of cholesterol in familial hypercholesterolaemia.

1. The present study investigated the role of intestinal cholesterol absorption in the regulation of cholesterol metabolism and serum lipoprotein levels in 22 patients with heterozygous familial hypercholesterolaemia on low to normal cholesterol intake. 2. The results showed that the higher the dietary cholesterol absorption, the lower was the overall synthesis of cholesterol. Efficient cholesterol absorption actually reduced the elimination of cholesterol as faecal neutral sterols but not consistently as bile acids. 3. In multifactorial analysis, body mass index and dietary plant sterols were negatively associated with cholesterol absorption, but were unrelated to cholesterol synthesis. 4. Fractional cholesterol absorption was related only to the serum very-low-density triacylglycerol level. It was not associated with the total or low-density lipoprotein cholesterol levels. On the other hand, cholesterol synthesis was significantly associated with the serum concentrations of very-low-density lipoprotein and intermediate-density lipoprotein cholesterol and triacylglycerols, and with those of low-density lipoprotein triacylglycerols. 5. In conclusion, dietary cholesterol absorption is an essential regulator of cholesterol homoeostasis in familial hypercholesterolaemia, even in patients on low cholesterol intake.

CHD and Its Risk Factors in the People's Republic of China

Mortality data obtained from the Health Statistics Office of the Ministry of Health, People's Republic of China (PRC), were compared to data for other countries taken from the World Health Statistics Annual. The crude death rate for coronary heart disease (CHD) in China in 1984 is estimated to be about one-tenth of that for North America and Australia. However, a high stroke to CHD ratio of about 5.0 was observed in China. The age-standardized CHD mortality rates were significantly higher for Beijing in north China than for Shanghai and Guangzhou in the south, and for urban than rural populations in all years from 1976 to 1986. Data on hospital admissions and autopsy material provide evidence for an increase in CHD incidence and prevalence in the last three to four decades. A low mean serum total cholesterol, related to a low habitual dietary intake of fat and cholesterol, is considered to be the main cause underlying low CHD mortality rates in China.

CHD and Its Risk Factors in the People's Republic of China

Mortality data obtained from the Health Statistics Office of the Ministry of Health, People's Republic of China (PRC), were compared to data for other countries taken from the World Health Statistics Annual. The crude death rate for coronary heart disease (CHD) in China in 1984 is estimated to be about one-tenth of that for North America and Australia. However, a high stroke to CHD ratio of about 5.0 was observed in China. The age-standardized CHD mortality rates were significantly higher for Beijing in north China than for Shanghai and Guangzhou in the south, and for urban than rural populations in all years from 1976 to 1986. Data on hospital admissions and autopsy material provide evidence for an increase in CHD incidence and prevalence in the last three to four decades. A low mean serum total cholesterol, related to a low habitual dietary intake of fat and cholesterol, is considered to be the main cause underlying low CHD mortality rates in China.

Concern about cholesterol and its association with diet in a group of healthy elderly

The association between diet and degree of concern about dietary cholesterol was examined in a group of 244 healthy elderly persons. Specifically, it was thought that a concern about cholesterol might result in diets that exclude essential nutrients, such as calcium and vitamin D, that are found in foods that also contain cholesterol. 70% of this group indicated a concern about dietary cholesterol; 18% were “very concerned”. Over half of these elderly thought that dietary cholesterol contributed to heart disease, atherosclerosis and high blood pressure. Many indicated that they were restricting their intake of certain foods because of cholesterol. This response was strongly associated with degree of concern about cholesterol. It was found that those who were concerned about cholesterol had lower intakes of cholesterol, total fat, saturated fat and total calories, and greater intakes of vitamin D. However, no other significant associations with diet were found.

Dietary studies of children from a biracial population: intakes of fat and fatty acids in 10-and 13-year olds

Dietary intakes of fat and fatty acids were examined in children randomly selected from a biracial community, Bogalusa, LA. Between two 10-yr-old groups examined 3 yr apart, temporal trends of 1) higher intakes of polyunsaturated fatty acids, linoleic and linolenic acids, and 2) lower intakes of animal fat, saturated fatty acids, and palmitic acid were documented. No racial differences were found, and the only difference between sexes was for myristic acid (boys > girls). Longitudinal comparisons of a cohort of 148 children examined at both 10 and 13 yr showed higher intakes over time of unsaturated fatty acids, polyunsaturated fatty acids, vegetable fat, oleic, linoleic, and linolenic acids, and lower intakes of cholesterol, saturated fatty acids, animal fat, and myristic acid. The percentage of energy intake from fat, saturated fatty acids and polyunsaturated fatty acids was quite similar to other reports of US children and adults. Few children's intakes of cholesterol, fat, and fatty acids were compatible with current recommendations for prudent diets. Patterns of dietary fat and fatty acid intake of Bogalusa children reflect reported food market trends of increased use of vegetable fats.

Reduction of risk factors for atherosclerosis in diabetic patients treated with a high-fiber diet

A protective effect of dietary fiber against atherosclerosis could be mediated through the influence of fiber on risk factors such as hyperlipidemia and hyperglycemia. To clarify this matter 14 diabetic patients (6 insulin-dependent and 8 noninsulin-dependent) were submitted, in metabolic ward conditions, to three weight maintaining diets for 10 days each: Diet A (carbohydrates 53%, lipids 30%, proteins 17%, fiber 20 g); Diet B, identical to diet A except for its fiber content (54 g); Diet C, lower in fiber and carbohydrates (carbohydrates 42%, lipids 37%, proteins 21%, fiber 20 g). The three diets were similar in their P S ratio and were composed only of natural foodstuffs. The 2-hr postprandial blood glucose concentration and the daily blood glucose were significantly lower during the high-fiber diet than during either diet A or C as were total and low-density lipoprotein (LDL) cholesterol. Very low-density lipoprotein triglyceride (VLDL-TG) was significantly lower during the high-fiber diet in comparison with diet A, but then did not change during diet C. The hypolipidemic effect of a fiber-rich diet was then evaluated in hyperlipidemic patients (type II) with diabetes ( n = 5) and without diabetes ( n = 6). LDL cholesterol was significantly reduced by the high-fiber diet in both groups. However, in diabetic patients LDL reduction was significantly higher than in nondiabetic patients ( P < 0.01). In conclusion, a high-fiber diet with lipid composition similar to southern Italian diets, composed only of natural foodstuffs, is able to reduce blood glucose and blood lipids in diabetic patients, over and above the effects of low saturated fat and low cholesterol intake. Moreover, it significantly reduces LDL-cholesterol in patients with type II hyperlipidemia and therefore can be utilized for prevention of atherosclerosis in the general population.