Lower Blood Cholesterol Concentrations Research Articles

Soy Protein Concentrate and Isolated Soy Protein Similarly Lower Blood Serum Cholesterol but Differently Affect Thyroid Hormones in Hamsters

There is a wide variation in the hypocholesterolemic response to ingestion of soy protein in humans. One possible explanation is that the different soy protein preparations used contain different spectra of biologically active components. This could affect a number of indices including thyroid hormone status. An increased level of thyroxine has been proposed as an underlying mechanism of the hypocholesterolemic effect of soy protein. The objective of this study was to determine if serum cholesterol and thyroid hormone concentrations differed because of feeding soy protein from different sources. Twenty-nine male weanling golden Syrian hamsters were fed rations containing 25 g/100 g protein from either isolated soy protein (ISP), soy protein concentrate (SPC) or casein for 35 d. Serum total cholesterol concentrations were lower in hamsters fed ISP and SPC compared with those fed casein (P < 0.05). No differences in cholesterol concentrations were observed in lipoprotein fractions. Serum thyroxine and free thyroxine were greater only in hamsters fed ISP than in those fed casein (P < 0.05), whereas triiodothyronine concentrations were higher in casein-fed than in SPC-fed hamsters (P < 0.05). Results indicate that protein from ISP and SPC are both effective in lowering blood cholesterol concentrations, whereas only ISP increases thyroxine concentrations. Therefore, it appears unlikely that modulation of thyroid hormone status is responsible for the cholesterol-lowering effect of soy protein.

Physiological and Productivity Performances of Japanese Quails Supplemented with Cassava Leaf Paste

This study aimed to evaluate and analyze the physiological performances of quails raised under this temperature range and then given cassava leaf paste to reduce the heat stress effects. The variables measured were blood chemical, stress indicators, body resistance, productivity, and quality of quail eggs. This experiment used 160 quails in a completely randomized design with 4 doses of cassava leaf paste as treatments with 4 replications, namely P0 (0 mg/g), P1 (5.29 mg/g), P2 (10.58 mg/g), and P3 (15.87 mg/g). The administration of cassava leaf paste for 30 days was carried out through 100 mL of drinking water for each dose. The results showed that administering various doses of cassava leaf paste to quails increased blood glucose and lower blood cholesterol concentrations. Administration of cassava leaf pastes in P3 treatment increased the oxygen saturation value of quail by 6.14% compared to the control treatment. Malondialdehyde (MDA) serum concentration as an indicator of oxidative stress significantly increased at a higher dose (P3) of cassava leaf paste administration. Meanwhile, the superoxide dismutase (SOD) serum concentration remains the same. Administration of cassava leaf pastes in P3 treatment decreased liver MDA by 66.66%, and P2 treatment increased liver SOD by 3.85% compared to the control treatment. The clearance test showed the presence of cassava leaf paste increased by 1.2% the death of Salmonella pullorum bacteria. The provision of cassava leaf paste can increase egg productivity and quality. The total cholesterol of egg yolks of quails receiving cassava leaf paste was lower than the control. In conclusion, applying cassava leaf paste can support the physiological performance such as blood chemistry (glucose levels, cholesterol, and oxygen saturation), stress indicators (serum and liver MDA and SOD concentrations), body resistance (total leukocyte count and the death rate of Salmonella pullorum bacteria), of quails, thereby increasing the productivity and quality of quail eggs.

Green tea catechin: does it lower blood cholesterol?

Tea is one of the most popular beverages in the world, especially in Asian societies. Green, oolong and black tea are three main types of tea products. Catechin is the principal polyphenol compound in all tea products including four major subgroup compounds, epigallocatechin gallate (EGCG), epicatehin (EC), epigallocatechin (EGC) and epicatechin gallate (ECG). Green tea contains highest amount of catechin compared to oolong and black tea since fermentation process can significantly reduce the amount of catechin in tea product, which polyphenol oxidase can convert catechins to theaflavins and thearubigins during fermentation process. Therefore, green tea catechin is becoming more and more attractive to nutritionists since it can provide several health benefits to human body. Cholesterol lowering effect is one of the health benefits been studied and proposed over decade. There are well documented evidences that suggested green tea catechin, in particular EGCG has the potential to lower blood cholesterol concentrations. Since the pool bioavailability and absorption ability of catechin, researchers believed that green tea catechin may significantly inhibit lipids absorption in intestine. Mechanisms are including inhibition of pancreatic lipase activity, lipids hydrolysis, and emulsification in intestine and precipitation of micellar cholesterol. In vitro studies, animal studies as well as most of human RCT, consistent results been observed that dietary intake of green tea beverages or extracts could significantly lower circulating cholesterol concentration, in particular lower LDL-C and total cholesterol level. However, in 2010, European Food Safety Authority (EFSA) denied the health claim of cholesterol lowering benefits of dietary intake of green tea or green tea catechins. In this presentation, current scientific evidences and EFSA judgment will be reviewed and discussed.

Roasting carob flour decreases the capacity to bind glycoconjugates of bile acids.

Carob is the fruit obtained from Ceratonia siliqua L. and it is a source of bioactive compounds that have been linked to several health promoting effects, including lowering blood cholesterol concentration. The objective of this study was to connect the physicochemical changes of carob flour occurring during roasting with its capacity to bind glycoconjugates of bile acids. Carob flour samples were roasted for different times at 150 °C and chemically characterized by measuring the concentrations of tannins and polyphenols. Data showed that carob flour binds high amounts of bile acids: 732.6 μmol of bound bile acid per g of carob flour which is comparable to the 836.2 μmol per g bound by cholestyramine, a known cholesterol lowering drug. The carob flour ability to bind cholesterol decreases up to 40% during roasting. Data suggested that tannins and insoluble components play a major role in binding bile salts, as a result of hydrophobic interactions.

The Lipid-lowering Effects and Associated Mechanisms of Dietary Phytosterol Supplementation.

Phytosterols (PS) are plant-based structural analogous of mammalian cholesterol that have been shown to lower blood cholesterol concentrations by ~10%, although inter-individual response to PS supplementation due to subject-specific metabolic and genetic factors is evident. Recent work further suggests that PS may act as effective triglyceride (TG)-lowering agents with maximal TG reductions observed in hypertriglyceridemic subjects. Although PS have been demonstrated to interfere with cholesterol and perhaps TG absorption within the intestine, they also have the capacity to modulate the expression of lipid regulatory genes through liver X receptor (LXR) activation. Identification of single-nucleotide polymorphisms (SNP) in key cholesterol and TG regulating genes, in particular adenosine triphosphate binding cassette G8 (ABCG8) and apolipoprotein E (apoE) have provided insight into the potential of utilizing genomic identifiers as an indicator of PS responsiveness. While PS supplementation is deemed safe, expanding research into the atherogenic potential of oxidized phytosterols (oxyphytosterols) has emerged with their identification in arterial lesions. This review will highlight the lipid-lowering utility and associated mechanisms of PS and discuss novel applications and future research priorities for PS pertaining to in utero PS exposure for long-term cardiovascular disease risk protection and combination therapies with lipidlowering drugs.

CHOLESTEROL LEVELS IN THE BLOOD AND FUNCTIONAL STATE OF TESTES IN INFERTILE MEN, PATIENTS WITH PRIMARY HYPOTHYROIDISM

Purpose of our study was to investigate how changing levels of testosterone in the blood and parameters spermogram in infertile men with hypothyroidism, depending on the presence or absence of hypercholesterolemia. We observed 49 infertile men aged 23–44 years, patients with primary hypothyroidism and 15 healthy men of the same age who was absent thyroid disease and disturbance of spermatogenesis (control group). Hypothyroidism patients were divided into two groups: those with a critical level of cholesterol (&gt; 5,2 mmol/l), and patients with lower blood cholesterol concentrations. It was found that in infertile men with primary hypothyroidism, there is an increase in total cholesterol in the blood that are associated with excess weight associated body. Hypercholesterolemia increases the frequency of non-compliance with the level of testosterone in the blood and reduce the number of sperm in the ejaculate of men with pathospermia with hypothyroidism. The increase in blood cholesterol levels in men with infertility hypothyroidism did not significantly affect the performance posttesticular sperm maturation, such as their mobility and vitality.

Sensory evaluation and effectiveness of natural drink for lowering blood cholesterol concentrations

The Koreans with the average serum cholesterol value ranged from 200~ 240 mg/dL are quite high, and thus it is a serious medical problem in the society. In this study, natural drink mostly made with medicinal herbs such as Albizzia julibrissin Durazz, Cassia tora L. seed, Maximowiczia chinensis, Morus alba L., and Glycyrrhiza uralensis was developed as anticholesterolemic drink. Sensory evaluation and anticholesterolemic effects of natural herbal drinks were tested. Sensory evaluation was performed by 146 panels (male 79, female 67) on the strength of color, flavor, taste, preference and overall acceptance based on 9 point‐hedonic scale. Anticholesterolemic effect of natural herbal drink was examined for serum lipid fractions by 15 adults at 0, 4, 8 and 12 week after use of one can (140 ml/can) a day. Sensory test results indicated that 6.0 pt was attained for the color, 5.3 pt., 4.1 pt., 5.7 pt. for flavor of Korean herbal medicine, astringent taste, and sweet taste, respectively. Overall acceptance(5.6 pt.) was not so high. However, the blood levels of total lipid, and triglyceride were decreased since after 8 weeks of the consumption and those of total cholesterol and LDL‐cholesterol also decreased significantly. From the findings, our natural herbal drink might be a good functional drink having anticholesterolemic effect. However, the natural herbal drink needs to be improved in the taste, flavor, and overall acceptance.

Session 4: CVD, diabetes and cancer A dietary portfolio for management and prevention of heart disease

CHD is the leading cause of worldwide mortality. The prevalence of heart disease has been linked to the adoption of a sedentary lifestyle and the increased dietary dependence on saturated fats from animal sources and the intake of refined foods. Elevated blood cholesterol level is one of the major risk factors for CHD. While cholesterol-lowering drug therapy (statins) has been effective in reducing the risk of heart disease, there are those individuals who are unwilling or because of muscle pains or raised levels of liver or muscle enzymes are unable to take cholesterol-lowering medication. Fortunately, there is evidence linking a number of dietary components to CHD risk reduction. The strength of this evidence has prompted various regulatory bodies to advocate diet as the first line of defence for primary prevention of heart disease. It was therefore decided to combine four dietary components that have been shown to lower blood cholesterol concentrations (nuts, plant sterols, viscous fibre and vegetable protein) in a dietary portfolio in order to determine whether the combined effect is additive. In a metabolically-controlled setting this dietary portfolio has proved to be as effective as a starting dose of a first-generation statin cholesterol-lowering medication in reducing the risk of CHD. The dietary portfolio has also been shown to be effective in sustaining a clinically-significant effect in the long term under a 'real-world' scenario. However, success of the diet depends on compliance and despite the accessibility of the foods adherence has been found to vary greatly. Overall, the evidence supports the beneficial role of the dietary portfolio in reducing blood cholesterol levels and CHD risk.

Mycoprotein and health

SummaryMycoprotein is a high protein, high fibre, low fat food ingredient derived from fermentation of the filamentous fungus Fusarium venenatum. Interest in the putative role of mycoprotein in lowering blood cholesterol concentrations, reducing energy intakes and controlling blood sugar levels has generated a small number of human studies investigating the effects of mycoprotein on cholesterol reduction, satiety and insulinaemia/glycaemia.In today's ‘obesogenic’ environment, in which there is an abundance of foods high in fat and/or sugar available to consumers, there is growing interest in foods that are both nutritious and satiating, but that are of low‐energy density, and are low in saturates, salt and sugar. Mycoprotein has a favourable fatty acid profile (being relatively low in saturates), a fibre content that is comparable with other vegetarian protein sources, and a naturally low sodium content. Mycoprotein is a good source of zinc and selenium but the levels of iron and vitamin B12 in mycoprotein are low in comparison to red meat.A small number of studies investigating the cholesterol‐lowering effects of mycoprotein have been carried out among normo‐ and hypercholesterolaemic adults. The published studies to date have a number of limitations (including small sample sizes and short study durations), but overall the studies report statistically significant reductions in total cholesterol amongst hypercholesterolaemic subjects (in the order of 4–14%). These results look promising in terms of the ability of mycoprotein to contribute modest but meaningful effects on blood cholesterol concentrations, as part of a varied and balanced diet. However, the exact amount of mycoprotein that would need to be consumed in free‐living populations to have meaningful effects on cholesterol is a candidate for further confirmatory research.A number of studies have investigated the effects of mycoprotein in comparison with other protein sources on satiety. Several studies suggest that the effects of mycoprotein on satiety are greater than an equivalent amount of chicken but it is unclear what mechanism underlies this. The studies conducted so far are relatively small, and carried out under controlled conditions, so it is difficult to extrapolate the results to larger free‐living populations.The promotion of mycoprotein could potentially be useful, alongside other strategies, in the management of obesity and type 2 diabetes, as it appears to show beneficial effects on glycaemia and insulinaemia in the small number of studies where this has been investigated. More research is needed to better understand the mechanism of action whereby mycoprotein influences glycaemia and insulinaemia, and whether there is any dose‐dependent effect.This paper reviews the published evidence for mycoprotein and the topics above, draws interim conclusions about the role of mycoprotein in human health and identifies areas for future research.

Does initial breastfeeding lead to lower blood cholesterol in adult life? A quantitative review of the evidence

BackgroundEarlier studies have suggested that infant feeding may program long-term changes in cholesterol metabolism. ObjectiveWe aimed to examine whether breastfeeding is associated with lower blood cholesterol concentrations in adulthood. DesignThe study consisted of a systematic review of published observational studies relating initial infant feeding status to blood cholesterol concentrations in adulthood (ie, aged >16 y). Data were available from 17 studies (17 498 subjects; 12 890 breastfed, 4608 formula-fed). Mean differences in total cholesterol concentrations (breastfed minus formula-fed) were pooled by using fixed-effect models. Effects of adjustment (for age at outcome, socioeconomic position, body mass index, and smoking status) and exclusion (of nonexclusive breast feeders) were examined. ResultsMean total blood cholesterol was lower (P = 0.037) among those ever breastfed than among those fed formula milk (mean difference: −0.04 mmol/L; 95% CI: −0.08, 0.00 mmol/L). The difference in cholesterol between infant feeding groups was larger (P = 0.005) and more consistent in 7 studies that analyzed “exclusive” feeding patterns (−0.15 mmol/L; −0.23, −0.06 mmol/L) than in 10 studies that analyzed nonexclusive feeding patterns (−0.01 mmol/L; −0.06, 0.03 mmol/L). Adjustment for potential confounders including socioeconomic position, body mass index, and smoking status in adult life had minimal effect on these estimates. ConclusionsInitial breastfeeding (particularly when exclusive) may be associated with lower blood cholesterol concentrations in later life. Moves to reduce the cholesterol content of formula feeds below those of breast milk should be treated with caution.

Decreased aortic early atherosclerosis and associated risk factors in hypercholesterolemic hamsters fed a high- or mid-oleic acid oil compared to a high-linoleic acid oil

Currently, diets higher in polyunsaturated fat are believed to lower blood cholesterol concentrations, and thus reduce atherosclerosis, greater than diets containing high amounts of saturated or possibly even monounsaturated fat. The present study was designed to investigate the effect of diets containing mid- or high-linoleic oil versus the typical high-linoleic sunflower oil on LDL oxidation and the development of early atherosclerosis in a hypercholesterolemic hamster model. Animals were fed a hypercholesterolemic diet containing 10% mid-oleic sunflower oil, high-oleic olive oil, or high-linoleic sunflower oil (wt/wt) plus 0.4% cholesterol (wt/wt) for 10 weeks. After 10 weeks of dietary treatment, only the animals fed the mid-oleic sunflower oil had significant reductions in plasma LDL-C levels (−17%) compared to the high-linoleic sunflower oil group. The high-oleic olive oil–fed hamsters had significantly higher plasma triglyceride levels (+41%) compared to the high-linoleic sunflower oil–fed hamsters. The tocopherol levels in plasma LDL were significantly higher in hamsters fed the mid-oleic sunflower oil (+77%) compared to hamsters fed either the high-linoleic sunflower or high-oleic olive oil. Measurements of LDL oxidation parameters, indicated that hamsters fed the mid-oleic sunflower oil and high-oleic olive oil diets had significantly longer lag phase (+66% and +145%, respectively) and significantly lower propagation rates (−26% and −44%, respectively) and conjugated dienes formed (−17% and −25%, respectively) compared to the hamsters fed the high-linoleic sunflower oil. Relative to the high-linoleic sunflower oil, aortic cholesterol ester was reduced by −14% and −34% in the mid-oleic sunflower oil and high-oleic olive oil groups, respectively, with the latter reaching statistical significance. Although there were no significant associations between plasma lipids and lipoprotein cholesterol with aortic total cholesterol and cholesterol esters for any of the groups, the lag phase of conjugated diene formation was inversely associated with both aortic total and esterified cholesterol in the high-oleic olive oil-fed hamsters ( r = −0.69, P < 0.05). The present study suggests that mid-oleic sunflower oil reduces risk factors such as lipoprotein cholesterol and oxidative stress associated with early atherosclerosis greater than the typical high-linoleic sunflower oil in hypercholesterolemic hamsters. The high-oleic olive oil not only significantly reduced oxidative stress but also reduced aortic cholesterol ester, a hallmark of early aortic atherosclerosis greater than the typical high-linoleic sunflower oil.

Effects of cholesterol-lowering with simvastatin on stroke and other major vascular events in 20 536 people with cerebrovascular disease or other high-risk conditions

Lower blood cholesterol concentrations have consistently been found to be strongly associated with lower risks of coronary disease but not with lower risks of stroke. Despite this observation, previous randomised trials had indicated that cholesterol-lowering statin therapy reduces the risk of stroke, but large-scale prospective confirmation has been needed. 3280 adults with cerebrovascular disease, and an additional 17256 with other occlusive arterial disease or diabetes, were randomly allocated 40 mg simvastatin daily or matching placebo. Subgroup analyses were prespecified of first "major vascular event" (ie, non-fatal myocardial infarction or coronary death, stroke of any type, or any revascularisation procedure) in prior disease subcategories. Subsidiary outcomes included any stroke, and stroke sub-type. Comparisons are of all simvastatin-allocated versus all placebo-allocated participants (ie, "intention-to-treat"), which yielded an average difference in LDL cholesterol of 1.0 mmol/L (39 mg/dL) during the 5-year treatment period. Overall, there was a highly significant 25% (95% CI 15-34) proportional reduction in the first event rate for stroke (444 [4.3%] simvastatin vs 585 [5.7%] placebo; p<0.0001), reflecting a definite 28% (19-37) reduction in presumed ischaemic strokes (p<0.0001) and no apparent difference in strokes attributed to haemorrhage (51 [0.5%] vs 53 [0.5%]; rate ratio 0.95 [0.65-1.40]; p=0.8). In addition, simvastatin reduced the numbers having transient cerebral ischaemic attacks alone (2.0% vs 2.4%; p=0.02) or requiring carotid endarterectomy or angioplasty (0.4% vs 0.8%; p=0.0003). The reduction in stroke was not significant during the first year, but was already significant (p=0.0004) by the end of the second year. Among patients with pre-existing cerebrovascular disease there was no apparent reduction in the stroke rate, but there was a highly significant 20% (8-29) reduction in the rate of any major vascular event (406 [24.7%] vs 488 [29.8%]; p=0.001). The proportional reductions in stroke were about one-quarter in each of the other subcategories of participant studied, including: those with coronary disease or diabetes; those aged under or over 70 years at entry; and those presenting with different levels of blood pressure or lipids (even when the pretreatment LDL cholesterol was below 3.0 mmol/L [116 mg/dL]). Much larger numbers of people in the present study suffered a stroke than in any previous cholesterol-lowering trial. The results demonstrate that statin therapy rapidly reduces the incidence not only of coronary events but also of ischaemic strokes, with no apparent effect on cerebral haemorrhage, even among individuals who do not have high cholesterol concentrations. Allocation to 40 mg simvastatin daily reduced the rate of ischaemic strokes by about one-quarter and so, after making allowance for non-compliance in the trial, actual use of this regimen would probably reduce the stroke rate by about a third. HPS also provides definitive evidence that statin therapy is beneficial for people with pre-existing cerebrovascular disease, even if they do not already have manifest coronary disease.

4P-0926 Wheat germ policosanol does not lower blood cholesterol concentrations in healthy adults

4P-0926 Wheat germ policosanol does not lower blood cholesterol concentrations in healthy adults

Disparity between angiographic regression and clinical event rates with hydrophobic statins

Statins are effective at lowering blood cholesterol concentration, and are given to patients with hypercholesterolaemia or hyperlipidaemia. Reduction of cholesterol concentration in serum can delay, or even regress, atherosclerotic lesions, leading to diminution of risk of cardiovascular disease. Results of studies have shown that the beneficial effects of statins depend not only on lowering cholesterol but also on many other factors. Production of mevalonic acid, a precursor of various essential substances for cell function (figure), is inhibited by hydrophobic statins.

The Scientific Evidence for a Beneficial Health Relationship Between Walnuts and Coronary Heart Disease

The author and four independent experts evaluated the intent and quality of scientific evidence for a potential beneficial health relationship between the intake of walnuts and the reduction and prevention of coronary heart disease. The report also addresses the supporting evidence for the health benefit of other tree nuts and selected legumes. Compared to most other nuts, which contain monounsaturated fatty acids, walnuts are unique because they are rich in n-6 (linoleate) and n-3 (linolenate) polyunsaturated fatty acids. Walnuts contain multiple health-beneficial components, such as having a low lysine:arginine ratio and high levels of arginine, folate, fiber, tannins, and polyphenols. Though walnuts are energy rich, clinical dietary intervention studies show that walnut consumption does not cause a net gain in body weight when eaten as a replacement food. Five controlled, peer-reviewed, human clinical walnut intervention trials, involving approximately 200 subjects representative of the 51% of the adult population in the United States at risk of coronary heart disease were reviewed. The intervention trials consistently demonstrated walnuts as part of a heart-healthy diet, lower blood cholesterol concentrations. None of these studies were of extended duration that would be essential for evaluation of the sustainability of the observed outcomes. These results were supported by several large prospective observational studies in humans, all demonstrating a dose response-related inverse association of the relative risk of coronary heart disease with the frequent daily consumption of small amounts of nuts, including walnuts.

The effect of HMG-CoA reductase inhibitors on chronic allograft rejection

Hydroxy-methyl-glutaryl coenzyme A (HMG-CoA) reductase inhibitors have pleiotropic actions that affect many systems other than lowering blood cholesterol concentrations. Hypercholesterolaemia is an adverse effect of immunosuppressive drug therapy and hence it is a common finding after organ transplantation. HMG-CoA reductase inhibitors lower cholesterol concentrations in transplant recipients but they also offer additional benefits. Since they impair the production of mevalonate, they reduce the concentrations of downstream products including farnesyl and geranyl phosphate. These isoprenoid moieties are required for protein prenylation and HMG-CoA reductase inhibitors impair this function in some cells. This action affects the immune system, especially in patients taking cyclosporin, and has been proposed as the mechanism whereby these drugs increase the half-life of transplanted organs. Other mechanisms have also been proposed including an increase in the free fraction of cyclosporin and a reduction in the time that low density lipoprotein (LDL) spends in blood. The latter effect reduces the extent of oxidation of LDL and hence reduces the damage caused by oxidised LDL. Chronic rejection is poorly understood but appears to involve both immune and non-immune processes. HMG-CoA reductase inhibitors affect both processes. At present, the evidence of benefit from statin prescription is confined to heart and kidney transplant recipients but it is likely that recipients of other organ transplants would also benefit. Drug interactions between cyclosporin and HMG-CoA reductase inhibitors are a limiting factor to their use. Pravastatin appears to be the best HMG-CoA reductase inhibitor for organ transplant recipients because of its lesser potential to interact with cyclosporin and hence cause myositis, which may thus allow higher doses to be used. Other, non-immunosuppressive drugs (including diltiazem and ketoconazole) have been shown to reduce transplant organ damage by unknown mechanisms and are widely prescribed in some transplant centres. More specific inhibitors of protein prenylation may afford useful immunosuppression, thereby prolonging transplant organ half-lives and also reducing the risk of cancer.

Cereals, legumes, and chronic disease risk reduction: evidence from epidemiologic studies

There is growing evidence that cereals and legumes play important roles in the prevention of chronic diseases. Early epidemiologic studies of these associations focused on intake of dietary fiber rather than intake of grains or legumes. Generally, these studies indicated an inverse association between dietary fiber intake and risk of coronary artery disease; this observation has been replicated in recent cohort studies. Studies that focused on grain or cereal intake are fewer in number; these tend to support an inverse association between intake of whole grains and coronary artery disease. Studies on the association of dietary fiber with colon and other cancers have generally shown inverse relations, but whether these relations are attributable to cereals, other fiber sources, or other factors is less clear. Although legumes have been shown to lower blood cholesterol concentrations, epidemiologic studies are few and inconclusive regarding the association of legumes with risk of coronary artery disease. It has been hypothesized that legumes, in particular soybeans, reduce the risk of some cancers, but epidemiologic studies are equivocal in this regard. Overall, there is substantial epidemiologic evidence that dietary fiber and whole grains are associated with decreased risk of coronary artery disease and some cancers, whereas the role of legumes in these diseases appears promising but as yet inconclusive.

Polymorphism of the apolipoprotein B gene and blood lipid concentrations in Japanese and Caucasian population samples

To examine whether a racial difference in apolipoprotein B (Apo B) gene polymorphism between Japanese and American Caucasians corresponds with the lower blood cholesterol concentrations in Japanese than in Americans, we examined the EcoRI polymorphism of the Apo B gene for 271 nonsmoking men and women aged 47–69 years in two population-based samples: rural Japanese living in Akita and Caucasians living in Minneapolis-St. Paul, Minnesota, USA. Mean values of serum cholesterol concentrations were significantly lower in Japanese than in Caucasians for both men and women (difference = 25–26 mg/dl). An allele-specific polymerase chain reaction was conducted to examine the EcoRI cutting site at the 12 669 cDNA position of the Apo B gene. The allele R2 (absence of the cutting site) has been associated with lower cholesterol concentrations in two previous studies. The frequency of the R2 allele was 6% for Japanese and 17% for Caucasians ( P < 0.001), and this race difference in allele frequency was identical for men and women. After controlling for age, body mass index, alcohol intake, and, for women, menopausal status and hormone replacement therapy, the adjusted mean (SE) cholesterol level among Japanese was 204 (3) mg/dl for genotype R1R1 and 185 (7) mg/dl for genotype R1R2 or R2R2 combined ( P = 0.01). The respective mean values among Caucasians were 224(5) mg/dl and 232(7) mg/dl ( P = 0.36). The polymorphism had a similar effect on total cholesterol concentrations for both men and women. The observed lower prevalence of the R2 allele in Japanese than in Caucasians indicates that this variation in the Apo B gene does not explain the racial difference in blood cholesterol concentrations.

Cholesterol's effect on patient education

<h3>To the Editor.—</h3> To the "cholesterol saga" presented in the December 19, 1990, issue ofThe Journal, we would like to add a "cost-misdeedness" analysis. The wave of enthusiasm for the beneficial effects of lowering blood cholesterol concentrations by pharmacological intervention in asymptomatic persons who are free of a history of coronary heart disease requires such an analysis. High plasma cholesterol levels are widely recognized as a major risk factor for heart disease and related mortality,^1,2but no evidence has yet been found that reducing cholesterol levels by drugs and diet can, in primary prevention trials, reduce total mortality.³ Since total mortality and long life expectancy are still considered nontrivial end points and since cost containment is a major public policy concern, the worrisome results of the three largest randomized primary prevention drug trials^4-8seem to ask for time for us to reflect before we introduce interventions. A

Effects of sources of dietary fat and protein on tissue cholesterol

Dietary variables were soy oil, beef tallow, soy protein, and casein. Dietary combinations were soy oil-soy protein, soy-oil casein, beef tallow-soy protein, and beef tallow-casein, and 96 rats were allotted randomly to the four isocaloric diets. [Crystalline cholesterol was added to standardize each diet at 0.2%.] Two randomly selected rats from each dietary group were killed at 0, 7, 9, 11, 13, 15, 18, 22, 30, 36, 42, and 48 days on experiment to determine the effects of sources (plant versus animal) of dietary fat and protein on tissue cholesterol concentrations and on cholesterogenesis in liver and small intestine. Feeding soy oil, a polyunsaturated fat, resulted in lower blood cholesterol concentrations, higher liver cholesterol concentrations, and lower intestinal cholesterogenesis than did feeding beef tallow, a saturated fat. Feeding soy protein, a plant protein, resulted in lower blood and liver cholesterol concentrations and less intestinal cholesterogenesis than did feeding casein, an animal protein. Hepatic cholesterogenesis and intestinal tissue cholesterol levels were not affected significantly by diet. Eight rats killed at day 0 had, on the average, lesser plasma cholesterol concentrations and greater rates of intestinal cholesterogenesis than rats fed experimental diets. Our results demonstrate that the hypocholesterolemic action of soy oil and soy protein fed to rats may be related to decreased intestinal cholesterogenesis. In addition, soy oil, a polyunsaturated fat caused a redistribution of cholesterol from plasma to liver.