Nutritional modulators of lipoprotein metabolism in patients with risk factors for coronary heart disease: diet and moderate exercise trial.

To study the role of diet as a risk factor for coronary heart disease (CHD), 463 adults (25-65 years, 419 males) at risk of or with CHD were assigned to group A (n = 231) receiving a cardiovasoprotective diet or group B (n = 232) receiving a normal diet in a randomized, single-blind fashion. Age, sex, risk factors and incidence of CHD were comparable between the two groups. Group A received a significantly higher percentage of calories in relation to complex carbohydrates, vegetable proteins, polyunsaturated fatty acids, and had a higher polyunsaturated:saturated fatty acid (P:S) ratio compared to control group B, which received more saturated fat and cholesterol. Group A also received more soluble dietary fiber and magnesium (Mg) and was physically more active than group B. Exercise and dietary adherence were tested by a questionnaire. After 12 weeks, results indicated a significant decrease in mean serum total cholesterol (9.0 vs 3.1%), low-density-lipoprotein cholesterol (LDL-C) (9.8 vs 3.8%) and triglyceride (11.1 vs 5.4%), and an increase in serum Mg (8.5%) in the intervention group compared to initial levels. No significant changes in mean levels were noted in the control group. Body weight significantly decreased and physical activity was significantly higher in the intervention group compared to the control group during the 12-week followup on similar intakes of energy. There were insignificant changes in high-density-lipoprotein cholesterol (HDL-C) in both groups.(ABSTRACT TRUNCATED AT 250 WORDS)     

Dietary modulators of lipid metabolism in the Indian diet-heart study (I.D.H.S.).

Of the 621 adults (25 to 65 years of age, 531 males) with either risk factors or with coronary heart disease (CHD) 310 subjects were given a cardiovasoprotective (CVP) diet (group A) and 311 subjects a normal diet (group B) in a randomized, single blind and controlled fashion. Risk factors and incidence of CHD were comparable between the two groups. The intervention group received a significantly higher percentage of calories in relation to complex carbohydrates, vegetable proteins, polyunsaturated fatty acids and high P:S ratio diet as compared to the control group. The control group received higher saturated fat and cholesterol. Compliance was assessed by dietary questionnaire during the follow-up. After 8 weeks of dietary trial, there was a significant decrease in mean serum total cholesterol (8.2 vs 2.1%), low density lipoprotein (LDL) cholesterol (9.8 vs. 2.7%) and triglyceride (11.2 vs 5.8%) in the intervention group compared to baseline levels and changes in control subjects. Body weight and physical activity at the entry to study and during the trial were similar in both groups. The decrease in mean HDL cholesterol were insignificant both in the intervention (4.3%) and control group (5.0%). There were no adverse effects of diet during the 8 weeks of trial. It is possible that a diet with 27.5% energy from total fat including 10.1% energy from monounsaturated fatty acids, P:S ratio 1.38, 120 mg dietary cholesterol, 26.0 g dietary fibre per 1000 kcal would modulate the lipid metabolism resulting in a significant reduction in serum total cholesterol, LDL cholesterol and triglyceride with no reduction in HDL cholesterol. This diet may be capable of reducing CHD incidence and mortality in the long term Indian diet-heart study (IDHS).     

Simple Nutrient-Based Rules vs. a Nutritionally Rich Plant-Centered Diet in Prediction of Future Coronary Heart Disease and Stroke: Prospective Observational Study in the US

To better understand nutrition paradigm shift from nutrients to foods and dietary patterns, we compared associations of a nutrient-based blood cholesterol-lowering diet vs. a food-based plant-centered diet with risk of coronary heart disease (CHD) and stroke. Participants were 4701 adults aged 18–30 years and free of cardiovascular disease at baseline, followed for clinical events from 1985 and 86 to 2018. A plant-centered diet was represented by higher A Priori Diet Quality Score (APDQS). A blood cholesterol-lowering diet was represented by lower Keys Score. Proportional hazards regression was used to calculate hazard ratios (HR). Higher APDQS showed a nutrient-dense composition that is low in saturated fat but high in fiber, vitamins and minerals. Keys Score and APDQS changes were each inversely associated with concurrent plasma low-density lipoprotein cholesterol (LDL-C) change. Over follow-up, 116 CHD and 80 stroke events occurred. LDL-C predicted CHD, but not stroke. APDQS, but not Keys Score, predicted lower risk of CHD and of stroke. Adjusted HRs (95% CIs) for each 1-SD higher APDQS were 0.73 (0.55–0.96) for CHD and 0.70 (0.50–0.99) for stroke. Neither low dietary fat nor low dietary carbohydrate predicted these events. Our findings support the ongoing shift in diet messages for cardiovascular prevention.     

Dietary fat and cardiovascular disease risk: quantity or quality?

When considering dietary fat quantity, there are two main factors to consider, impact on body weight and plasma lipoprotein profiles. Data supporting a major role of dietary fat quantity in determining body weight are weak and may be confounded by differences in energy density, dietary fiber, and dietary protein. With respect to plasma lipoprotein profiles, relatively consistent evidence indicates that under isoweight conditions, decreasing the total fat content of the diet causes an increase in triglyceride and decrease in high-density lipoprotein (HDL) cholesterol levels. When considering dietary fat quality, current evidence suggests that saturated fatty acids tend to increase low-density lipoprotein (LDL) cholesterol levels, whereas monounsaturated and polyunsaturated fatty acids tend to decrease LDL cholesterol levels. Long-chain omega-3 fatty acids, eicosapentaenoic acid (EPA) (20:5n-3) and docosahexaenoic acid (DHA) (22:6n-3), are associated with decreased triglyceride levels in hypertriglyceridemic patients and decreased risk of developing coronary heart disease (CHD). Dietary trans-fatty acids are associated with increased LDL cholesterol levels. Hence, a diet low in saturated and trans-fatty acids, with adequate amounts of monounsaturated and polyunsaturated fatty acids, especially long-chain omega-3 fatty acids, would be recommended to reduce the risk of developing CHD. Additionally, the current data suggest it is necessary to go beyond dietary fat, regardless of whether the emphasis is on quantity or quality, and consider lifestyle. This would include encouraging abstinence from smoking, habitual physical activity, avoidance of weight gain with age, and responsible limited alcohol intake (one drink for females and two drinks for males per day).     

Diet and coronary heart disease

The controversy over the role of diet in the development of coronary heart disease (CHD) continues. Most studies of dietary involvement have concentrated on the possible nutritional basis of the accepted risk factor - raised serum cholesterol. In animals, although high fat diets, particularly high saturated fatty acid diets, cause raised serum cholesterol levels, myocardial infarction rarely occurs. In human studies initial insight into the importance of dietary fat level and fatty acid composition was gleaned from international studies. Within population studies supported the association of raised serum cholesterol concentration with CHD in males up to 60years of age, and recognised the significance of the type of serum cholesterol, currently thought to be under genetic control. Although intervention studies have shown that high serum cholesterol levels can be reduced by dietary means, there has been no convincing evidence of a reduction in total mortality. An imbalance in the formation of inhibitors and promoters of platelet aggregation from polyunsaturated fatty acids in the diet is postulated as a possible nutritional basis for the formation of a thrombus in the coronary artery.     

Coconut fat and serum lipoproteins: effects of partial replacement with unsaturated fats

The aim of the present study was to examine the effect of reducing saturated fat in the diet, or partly replacing it with unsaturated fat, on the serum lipoprotein profile of human subjects. The study had two intervention periods, 8 weeks (phase 1) and 52 weeks (phase 2). In phase 1, total fat was reduced from 31 to 25% energy (polyunsaturated fatty acids (PUFA):saturated fatty acids (SFA) ratio increased from 0.2 to 0.4) by reducing the quantity of coconut fat (CF) in the diet from 17.8 to 9.3% energy intake. In phase 2, subjects were randomised to groups A and B. In group A total fat was reduced from 25 to 20% energy (PUFA:SFA ratio increased from 0.4 to 0.7) by reducing the quantity of CF in the diet from 9.3 to 4.7% total energy intake. In group B, the saturated fat content in the diet was similar to group A. In addition a test fat (a mixture of soyabean oil and sesame oil, PUFA:monosaturated fatty acids ratio 2) contributed 3.3% total energy intake and total fat contributed 24% energy intake (PUFA:SFA ratio increased from 0.7 to 1.1). At the end of phase 1, there was a 7.7% reduction in cholesterol (95% CI -3.6, -12.2) and 10.8% reduction in LDL (95% CI -4.9, -16.5) and no significant change in HDL and triacylglycerol. At the end of phase 2, the reduction in cholesterol in both groups was only about 4% (95% CI -12, 3.2) partly due the concomitant rise in HDL. The reduction in LDL at 52 weeks was significantly higher in group B (group A mean reduction 11%, 95% CI -20.1, -2.0 and group B mean reduction 16.2% 95% CI -23.5, -8.9). In phase 2, triacylglycerol levels showed a mean reduction of 6.5% in group 2A and a mean increase of 8.2% in group 2B. The reduction of saturated fat in the diet is associated with a lipoprotein profile that would be expected to reduce cardiovascular risk. The reduction of dietary saturated fat with partial replacement of unsaturated fat brings about changes in total cholesterol, HDL- and LDL-cholesterol that are associated with a lower cardiovascular risk.     

Low-fat and high-monounsaturated fatty acid diets decrease plasma cholesterol ester transfer protein concentrations in young, healthy, normolipemic men

BACKGROUND: Cholesterol ester transfer protein (CETP) mediates the transfer of cholesteryl esters from HDL to apolipoprotein (apo) B-containing lipoproteins. The possible atherogenic role of this protein is controversial. Diet may influence plasma CETP concentrations. OBJECTIVE: The objective was to determine whether the changes in plasma lipids observed after consumption of 2 lipid-lowering diets are associated with changes in plasma CETP concentrations. DESIGN:: We studied 41 healthy, normolipidemic men over 3 consecutive 4-wk dietary periods: a saturated fatty acid-rich diet (SFA diet: 38% fat, 20% saturated fat), a National Cholesterol Education Program Step I diet (NCEP Step I diet: 28% fat, 10% saturated fat), and a monounsaturated fatty acid-rich diet (MUFA diet: 38% fat, 22% monounsaturated fat). Cholesterol content (27.5 mg/MJ) was kept constant during the 3 periods. Plasma concentrations of total, LDL, and HDL cholesterol; triacylglycerol; apo A-I and B; and CETP were measured at the end of each dietary period. RESULTS: Compared with the SFA diet, both lipid-lowering diets significantly decreased plasma total and LDL cholesterol, apo B, and CETP. Only the NCEP Step I diet lowered plasma HDL cholesterol. Positive, significant correlations were found between plasma CETP and total (r = 0.3868, P < 0.0001) and LDL (r = 0.4454, P < 0.0001) cholesterol and also between changes in CETP concentrations and those of total (r = 0.4543, P < 0.0001) and LDL (r = 0.4554, P < 0.0001) cholesterol. CONCLUSIONS: The isoenergetic substitution of a high-saturated fatty acid diet with an NCEP Step I or a high-monounsaturated fatty acid diet decreases plasma CETP concentrations.     

The relationship of dietary fat and cholesterol to mortality in 10 years: the Honolulu Heart Program

This report examines the relationship of dietary fat and dietary cholesterol to mortality during a 10-year surveillance of a cohort of men of Japanese descent residing in Hawaii. The consumption of dietary fat (measured in grams) is related inversely and significantly to total mortality. No significant relationships exist between grams of dietary fat and any of the specific causes of death examined. No significant relationships are found between dietary saturated fatty acids (SFA, measured in grams) or dietary cholesterol (measured in milligrams) and any of the specific causes of death examined. In contrast, percentage of calories as fat is related inversely not only to total mortality, but to cancer mortality and to stroke mortality; and it is related directly to coronary heart disease (CHD) mortality. Percentage of calories as SFA is related inversely to cancer mortality and to stroke mortality, and it is related directly to CHD mortality. Only the relationship to stroke mortality remains significant in multivariate analysis if calories from alcohol are excluded from the computation. Dietary cholesterol per 1000 calories is related directly to CHD mortality. While these data provide support for the diet-heart hypothesis, they also suggest that men with low fat intakes have a higher total mortality rate than men with higher fat intakes. This increased risk, due to an excess risk of death from stroke and cancer, indicates that there is no overall beneficial effect from a low fat diet in this cohort.     

Effects of diets rich in monounsaturated fatty acids on plasma lipoproteins--the Jerusalem Nutrition Study. II. Monounsaturated fatty acids vs carbohydrates.

Seventeen male Yeshiva students were randomly allocated to a crossover study with two 12-wk dietary periods of monounsaturated fatty acids (MUFAs) vs a carbohydrate (CHO)-rich diet while concentrations of saturated (SFAs) and polyunsaturated (PUFAs) fatty acids were kept similar. Total plasma cholesterol (TC) decreased significantly by approximately 7.7% and low-density-lipoprotein cholesterol (LDL-C) by 14.4% on the MUFA diet, whereas on the CHO diet no significant change in cholesterol concentrations occurred, in contrast to that predicted by the equations of Keys and Hegsted. Concentrations of high-density-lipoprotein cholesterol (HDL-C) did not change significantly on either diet. On the MUFA diet there was a significantly lower proneness to peroxidation of plasma and LDL lipids and less extensive metabolism of conditioned LDL by peritoneal macrophages. We conclude that dietary MUFAs lower TC and LDL-C concentrations, independently of other dietary fatty acids and in addition may reduce the susceptibility of LDL to oxidative stress.     

Coronary-heart-disease risk-factor status of the Cretan urban population in the 1980s

The traditional Cretan diet has been associated with low coronary-heart-disease (CHD) mortality rates. This study reports on the prevalence of CHD risk factors among 387 Cretan bank employees. Mean cholesterol concentration has risen by 36% over 26-y; dietary intake has changed: consumption of meat, fish, and cheese has increased and consumption of bread, fruit, and potatoes has decreased. Although the percentage contribution of fat to total energy intake has decreased from 40% to 36%, there has been a reduction in monounsaturated fatty acid consumption and an increase in the consumption of saturated fatty acids whereas the consumption of polyunsaturates has not been altered. Exception for diminished physical activity, the prevalence of other risk factors (smoking, blood pressure, and body mass index) remained relatively stable over this period. These changes in the CHD risk-factor status of the Cretan urban population occurred over a period in which CHD mortality rates are reported to have increased.     

The effect of diet and aspirin on patient outcome after myocardial infarction.

Recent studies show that diet and aspirin therapy inhibit platelet aggregation and may independently reduce complications and mortality in patients after acute myocardial infarction (AMI). To compare the effects of diet and aspirin, 140 patients, who were 4-6 wk post acute myocardial infarction, were assigned either to Group A (placebo with cardiovasoprotective diet) or Group B (aspirin [180 mg daily]) with fat-modified control diet in a single-blind controlled fashion. Of the 140 patients, 7 left the trial before it was completed. Of the remaining 133 patients, 68 in Group A and 65 in Group B were followed for one year. When the study began, the following factors were comparable for both groups: mean age, sex, risk factors, complications of myocardial infarction, electrocardiographic changes, and laboratory data. Group A received a significantly higher caloric intake (P less than 0.02) from complex carbohydrates, vegetable proteins, polyunsaturated fats, and larger amounts of dietary fibers, potassium, magnesium, and vitamin C compared with Group B, which received significantly larger amounts of saturated fats and cholesterol (P less than 0.01). The rehabilitation program, which included reduced smoking, increased exercise and drug therapy, was comparable in both groups. After one year, mean serum cholesterol (223.2 +/- 32.0 mg/dl) and triglyceride (156.2 +/- 13.5 mg/dl) levels in Group A, but not in Group B, were significantly (P less than 0.02) lower compared with mean serum cholesterol (241.2 +/- 39.5 mg/dl) and triglyceride (175.5 +/- 18.5 mg/dl) levels at the beginning of the study.(ABSTRACT TRUNCATED AT 250 WORDS)     

Dietary fat intake and risk of coronary heart disease: the Strong Heart Study

BACKGROUND: The results of previous studies on the association between dietary fat intake and coronary heart disease (CHD) incidence are inconsistent. OBJECTIVE: The aim of this study was to examine the association between dietary fat intake and CHD incidence in American Indians in the Strong Heart Study. DESIGN: A total of 2938 participants aged 47-79 y and free of CHD at the second examination (1993-1995) were examined and followed for CHD, nonfatal CHD, and fatal CHD events to 31 December 2002. Dietary intake was assessed by using a 24-h diet recall and was calculated as percentages of energy. RESULTS: Participants were followed for a mean (+/-SD) of 7.2 +/- 2.3 y. During follow-up, 436 incident CHD cases (298 nonfatal CHD and 138 fatal CHD events) were ascertained. Participants aged 47-59 y in the highest quartile of intake of total fat, saturated fatty acids, or monounsaturated fatty acids had higher CHD mortality than did those in the lowest quartile [hazard ratio (95% CI): 3.57 (1.21, 10.49), 5.17 (1.64, 16.36), and 3.43 (1.17, 10.04), respectively] after confounders were controlled for. These associations were not observed for those aged 60-79 y. CONCLUSIONS: Total fat, saturated fatty acid, and monounsaturated fatty acid intake were strong predictors of CHD mortality in American Indians aged 47-59 y, independent of other established CHD risk factors. It may be prudent for American Indians to reduce their fat intake early in life to reduce the risk of dying from CHD.     

Plasma lipid changes in young adult couples consuming polyunsaturated meats and dairy products.

Twenty-five young couples consumed either a saturated or polyunsaturated fat diet for a 20-week period. The polyunsaturated beef, lamb and dairy products, high in linoleic acid, were produced by feeding ruminant animals "protected lipid" feeds which prevent hydrogenation of fats in the rumen. The experimental design provided for four dietary groups: A) saturated diet for 20 weeks; B) polyunsaturated diet for 20 weeks; C) saturated diet for 10 weeks then polyunsaturated diet for 10 weeks; and D) polyunsaturated for 10 weeks then saturated diet for 10 weeks. Polyunsaturated-to-saturated ratios (linoleic: total saturated fatty acids) for the diets were: prestudy, 0.43-0.56; saturated 0.11-0.14; polyunsaturated, 0.56-0.62. Factors other than diet that appeared to affect cholesterol responses were carefully considered. During the initial 3 weeks (regimentation period) plasma cholesterol concentration decreased in all groups irrespective of diet. This was followed by two experimental periods in which the effects of the prescribed diets were readily apparent (response periods I and II). The final 4 weeks of the study were characterized by diminishing compliance with the dietary discipline (abatement period). Subjects in each group (A,B,C,D) were subdivided into high and low on a basis of each group's initial median cholesterol level. Those in the high subgroups were very responsive to dietary changes whereas those in the low subgroups were not. Combined responses of high subjects were: polyunsaturated diet, -10.7 mg/dl (P less than 0.025), saturated diet, d8 mg/dl (P less than 0.05). Combined difference between saturated and polyunsaturated diets was 18.5 mg/dl or approximately a 10% cholesterol difference between the experimental polyunsaturated and saturated diets.     

Modern fat technology: what is the potential for heart health?

Saturated and trans-fatty acids raise total cholesterol and LDL-cholesterol and are known to increase the risk of CHD, while dietary unsaturated fatty acids play important roles in maintaining cardiovascular health. Replacing saturated fats with unsaturated fats in the diet often involves many complex dietary changes. Modifying the composition of foods high in saturated fat, particularly those foods that are consumed daily, can help individuals to meet the nutritional targets for reducing the risk of CHD. In the 1960s the Dutch medical community approached Unilever about the technical feasibility of producing margarine with a high-PUFA and low-saturated fatty acid composition. Margarine is an emulsion of water in liquid oil that is stabilised by a network of fat crystals. In-depth expertise of fat crystallisation processes allowed Unilever scientists to use a minimum of solid fat (saturated fatty acids) to structure a maximum level of PUFA-rich liquid oil, thus developing the first blood-cholesterol-lowering product, Becel. Over the years the composition of this spread has been modified to reflect new scientific findings and recommendations. The present paper will briefly review the developments in fat technology that have made these improvements possible. Unilever produces spreads that are low in total fat and saturated fat, virtually free of trans-fatty acids and with levels of n-3 and n-6 PUFA that are in line with the latest dietary recommendations for the prevention of CHD. Individuals with the metabolic syndrome have a 2-4-fold increased risk of developing CHD; therefore, these spreads could make a contribution to CHD prevention in this group. In addition, for individuals with the metabolic syndrome the spreads could be further modified to address their unique dyslipidaemia, i.e. elevated blood triacylglycerols and low HDL-cholesterol. Research conducted in the LIPGENE study and other dietary intervention studies will deliver the scientific evidence to justify further modifications in the composition of spreads that are healthy for the heart disease risk factors associated with the metabolic syndrome.     

Reducing total dietary fat without reducing saturated fatty acids does not significantly lower total plasma cholesterol concentrations in normal males.

Forty-eight healthy male students ate an average American diet (AAD) with 37% of calories from fat and 16% from saturated fatty acids for 3 wk. During the next 7 wk, one-third of the students continued to eat the AAD, one-third switched to a 30%-fat diet with 9% saturated fatty acids (Step 1 diet), and one-third switched to a 30%-fat diet with 14% saturated fatty acids (Sat diet). The Step 1 group had a significant reduction in plasma total cholesterol (TC) (0.36 +/- 0.37 mmol/L) compared with the AAD group (0.07 +/- 0.39 mmol/L) and the Sat group (0.08 +/- 0.25 mmol/L). The Sat group did not differ from the AAD group. Changes in low-density-lipoprotein (LDL) cholesterol paralleled changes in total cholesterol. High-density-lipoprotein cholesterol fell significantly in the Step 1 group (0.11 +/- 0.08 mmol/L) compared with the AAD group. Plasma triglycerides did not differ between groups at the end of the randomized periods. In summary, reduction of dietary fat intake from 37% to 30% of calories did not lower plasma total and LDL cholesterol concentrations unless the reduction in total fat was achieved by decreasing saturated fatty acids.     

Lipoproteins, nutrition, and heart disease

This article reviews the current status of our knowledge of lipoproteins, nutrition, and coronary heart disease (CHD). Special emphasis is placed on CHD risk assessment, dietary intervention studies, diet-gene interactions, and current dietary guidelines and the contributions of my laboratory to these areas. CHD remains a major cause of death and disability, and risk factors include age, sex, hypertension, smoking, diabetes, elevated serum LDL cholesterol, and low HDL cholesterol. Emerging independent risk factors include elevated serum concentrations of lipoprotein(a), remnant lipoproteins, and homocysteine. The cornerstone of CHD prevention is lifestyle modification. Dietary intervention studies support the concepts that restricting saturated fat and cholesterol and increasing the intake of essential fatty acids, especially n - 3 fatty acids, reduces CHD risk. The variability in LDL-cholesterol response to diet is large, related in part to APOE and APOA4 genotype. The use of antioxidants in intervention studies has not been shown to reduce CHD risk. Compliance with dietary recommendations remains a major problem, and directly altering the food supply may be the most effective way to ensure compliance. The available data indicate that the recommendation to use fats, oils, and sugars sparingly for CHD prevention should be modified to a recommendation to use animal, dairy, and hydrogenated fats; tropical oils; egg yolks; and sugars sparingly and to increase the use of vegetables, fruit, and whole grains.     

Types of dietary fat and risk of coronary heart disease: a critical review

During the past several decades, reduction in fat intake has been the main focus of national dietary recommendations to decrease risk of coronary heart disease (CHD). Several lines of evidence. however, have indicated that types of fat have a more important role in determining risk of CHD than total amount of fat in the diet. Metabolic studies have long established that the type of fat, but not total amount of fat, predicts serum cholesterol levels. In addition, results from epidemiologic studies and controlled clinical trials have indicated that replacing saturated fat with unsaturated fat is more effective in lowering risk of CHD than simply reducing total fat consumption. Moreover, prospective cohort studies and secondary prevention trials have provided strong evidence that an increasing intake of n-3 fatty acids from fish or plant sources substantially lowers risk of cardiovascular mortality. In this article, we review evidence from epidemiologic studies and dietary intervention trials addressing the relationship between dietary fat intake and risk of CHD, with a particular emphasis on different major types of fat, n-3 fatty acids and the optimal balance between n-3 and n-6 fatty acids. We also discuss the implications of the available evidence in the context of current dietary recommendations.     

Impact of receiving blood cholesterol test results on dietary change

Introduction: The study objective was to determine the impact of receivin results of a blood cholesterol test on changes in dietary behaviors among individuals participating in a Health Risk Appraisal Program.Methods: This randomized trial of maintenance employees at six hospitals included two groups: Group 1 received their blood cholesterol test results at the pretest; Group 2 received results only at the posttest (16–20 weeks later). The pretest interview included (1) a 24-hour dietary recall; (2) an evaluation of dietary behaviors and suggestions on how to change; (3) height, weight, and blood cholesterol measurement. Five hundred employees participated, and 429 eligible employees completed both pretest and posttest interviews.Results: Blood cholesterol levels decreased by 4.8% (P < .001) and saturated fat intake decreased by 7.4% (P < .05). Regression analyses indicated that individuals more likely to have lowered saturated fat intake had higher pretest saturated fat intakes, had a family history of high blood cholesterol, and were light-maintenance employees (P < .05); no other variables were associated (receiving blood cholesterol test results, previous blood cholesterol test, pretest blood cholesterol levels, personal history of heart disease, BMI, age, gender, tobacco/alcohol use). Among subjects with normal cholesterol levels, those not receiving blood test results reduced saturated fat intake more than those receiving test results; both groups had similar saturated fat intakes (>12%) greater than recommended intake (<10%).Conclusions: Screening programs should include an assessment of saturated fat intake as screening for blood cholesterol may provide normocholesterolemic subjects with a false sense of security.     

Plasma lipid and lipoprotein responsiveness to dietary fat and cholesterol in premenopausal African American and white women

BACKGROUND: Premenopausal African American women have a 2-3 times greater incidence of coronary heart disease (CHD) than do white women. The plasma lipid responsiveness to dietary fat, which may be associated with CHD, has not been adequately studied in premenopausal African American or white women. OBJECTIVE: The objective of our study was to compare the effect of diet on fasting plasma lipids and lipoproteins and postprandial lipemia in premenopausal African American and white women. DESIGN: Thirteen African American and 9 white healthy premenopausal women were fed a low-fat, high-fiber diet and a high-fat, low-fiber diet for 4 wk each in a randomized crossover design. Fasting plasma lipid and lipoprotein concentrations and the 24-h plasma triacylglycerol response to a standard fatty test meal were measured at the end of each dietary period. RESULTS: Plasma total and LDL-cholesterol concentrations were higher after the high-fat, low-fiber diet in both white and African American women (P < 0.0001). The 24-h area under the plasma triacylglycerol curve after the test meal was lower after the low-fat diet than after the high-fat diet (P < 0.04). CONCLUSIONS: African American and white women had lower fasting plasma total and LDL-cholesterol concentrations and less postprandial lipemia after the low-fat than the high-fat diet. Diets low in total and saturated fat and cholesterol and high in fiber may reduce the risk of CHD by lowering fasting plasma total and LDL-cholesterol concentrations and by reducing the lipemic response to fatty meals.     

Lipid profile of rats fed high-fat diets based on flaxseed, peanut, trout, or chicken skin

OBJECTIVE: Dietary saturated fatty acids are associated with coronary disease. Conversely, dietary monounsaturated polyunsaturated fatty acids (MUFAs) and polyunsaturated fatty acids (PUFAs) seem to exert a protective effect. This study evaluated the lipid profile of rats fed high-fat (HF) diets, with fat added as different sources of PUFA (flaxseed and trout), MUFA (peanut), and saturated fatty acid (chicken skin). METHODS: Adult male Wistar rats were placed into six dietary groups (n = 10): control (normal); high fat, with 1% cholesterol, 10% soy oil, and 5% lard; and four groups fed similar HF diets, with 10% lipid as trout, flaxseed, peanut, or chicken skin. After 28 d the animals were killed. Blood, livers, and adipose tissue samples were collected. RESULTS: A higher level (P < 0.05) of total serum cholesterol was observed in rats fed the normal diet (93.57 +/- 14.95 mg/dL) compared with those fed the HF diet (67.57 +/- 12.54 mg/dL). Total cholesterol levels in rats fed the flaxseed diet were lower (P < 0.05) than in rats fed the other fats. No difference was observed in cholesterol levels between groups fed the peanut and chicken skin diets (P > 0.05). Animals fed the peanut diet showed decreased body weight gain than did animals in the other treatment groups. There were large lipid and cholesterol depositions in livers of rats fed the HF diet. Lipid deposition in adipose tissue followed the same dietary fatty acid profile, i.e., high levels of omega-3 PUFA in the flaxseed group, high levels of MUFA in the peanut and chicken skin groups and high levels of omega-6 PUFA in the trout group. CONCLUSIONS: These data indicate that flaxseed is promising for dietary manipulation of hyperlipidemia.