Cholesterol serum levels

The Problem. Suppose that the total serum cholesterol level in normal adults has been established as 200mg/100mL (mg%) with a standard deviation of 25 mg%, that is, p = 200 and ct = 25. (Please distinguish between mg% and % probability.) A patient s serum is analyzed for cholesterol and found to contain 265 mg% total cholesterol. 

The intermediate m hydrogenation formed by reaction of the unsaturated ester with the hydrogenated surface of the metal catalyst not only can proceed to the saturated fatty acid ester but also can dissociate to the original ester having a cis double bond or to its trans stereoisomer Unlike polyunsaturated vegetable oils which tend to reduce serum cholesterol levels the trans fats produced by partial hydrogenation have cholesterol raising effects similar to those of saturated fats... 

Thus, it is apparent that soya, some soya products and linseed oil influence blood lipid levels, particularly cholesterol and LDL cholesterol. While the extent of the reduction appears to largely depend on an individual s initial serum cholesterol level, the maximum reductions observed are of the order of 10-15%. For hyperlipidemic individuals this may not be a marked reduction, but such an effect on the general population may well have a beneficial effect on the overall incidence of cardiovascular disease and atherosclerosis. The possibility that non-phytoestrogenic dietary components may contribute to the hypocholes-terolemic properties cannot, however, be discounted. Indeed, certain types of dietary fibre have been shown to have a hypolipidemic effect via their ability to increase faecal excretion rates. 

Derivatives of lovastatin have been found to be even more potent in cholesterol-lowering trials. Synvinolin lowers serum cholesterol levels at much lower doses than lovastatin. 

We hear a lot these days about the relationships between saturated fats, cholesterol, and heart disease. What are the facts It s well established that a diet rich in saturated animal fats often leads to an increase in blood serum cholesterol, particularly in sedentary, overweight people. Conversely, a diet-lower in saturated fats and higher in polyunsaturated fats leads to a lower serum cholesterol level. Studies have shown that a serum cholesterol level greater than 240 mg/dL (a desirable value is <200 mg/dL) is correlated with an increased incidence of coronary artery disease, in which cholesterol deposits build up on the inner walls of coronary arteries, blocking the flow of blood to the heart muscles. 

Medicinal chemistry has frequently drawn inspiration and important new leads from the examination of natural products, and this was proven to be the case once more. In 1992, researchers at Merck and Glaxo announced, almost simultaneously, the independent discovery of the same new class of natural products from two different fungi. As a consequence, the same family of natural products has two names - the zaragozic acids (Merck)4 or the squalestatins (Glaxo).5 A typical member of the family, zaragozic acid A (squa-lestatin SI) (1) was shown to have a tremendous affinity for squalene synthase (K, = 79 pM for rat microsomal squalene synthase) and could even lower serum cholesterol levels in vivo in a population of marmosets.6... 

Cardiovascular disease (CVD) is one of the leading causes of death worldwide. There are a number of established risk factors including serum cholesterol levels, smoking and family history, which are responsible for between 50 and 75% of the CVD cases, with the remainder due to factors that cause atherosclerosis. Estrogen treatment such as hormone replacement therapy is known to protect against CVD by decreasing the levels of low-density... 

With investigations of phytochemicals and functional foods, the outcome measure is generally going to be a biomarker of disease, such as serum cholesterol level as a marker of heart disease risk, or indicators of bone turnover as markers of osteoporosis risk. Alternatively, markers of exposure may also indicate the benefit from a functional food by demonstrating bioavailability, such as increased serum levels of vitamins or carotenoids. Some components will be measurable in both ways. For instance, effects of a folic acid-fortified food could be measured via decrease in plasma homocysteine levels, or increase in red blood cell folate. 

SUGANO M, ISHIWAKI N, NAKASHIMA K (1984) Dietary protein-dependent modification of serum cholesterol level in rats significance of Arginine/lysine ratio. rinw Nutr Metab, 28 192-9. 

The development of CHD is a lifelong process. Except in rare cases of severely elevated serum cholesterol levels, years of poor dietary habits, sedentary lifestyle, and life-habit risk factors (e.g., smoking and obesity) contribute to the development of atherosclerosis.3 Unfortunately, many individuals at risk for CHD do not receive lipid-lowering therapy or are not optimally treated. This chapter will help identify individuals at risk, assess treatment goals based on the level of CHD risk, and implement optimal treatment strategies and monitoring plans. 

Cafestol from robusta coffee as well as kahweol from arabica coffee were both recognized as capable of elevating serum cholesterol levels.124... 

Heavy coffee drinking raises the levels of plasma homocysteine, a risk for heart disease. The dose response of plasma homocysteine to coffee appears stronger than the association to serum cholesterol levels. Heavy coffee consumption was found to cause an increase of about 2 mmol/... 

The experimental studies cited below have isolated and tested the impact of caffeine, different methods of preparation, and different chemical fractions of coffee beans on serum cholesterol levels over a varied range of time periods. 

The failure to find an effect in the American trial above was confirmed in a study conducted in the Netherlands, which also used paper-filtered, drip-brewed coffee.14 In that 12-week experiment, 23 women and 22 men who habitually drank 4 to 6 cups of coffee per day were assigned to consume 5 cups/day of either caffeinated (417.5 mg caffeine/day) or decaffeinated coffee (15.5 mg caffeine/day) for six weeks, and then switch for another six weeks. The blend of coffee beans was 71% Arabica and 29% Robusta for the caffeinated coffee, and 58% Arabica and 42% Robusta for the decaffeinated coffee. Lipid values at the end of both six-week study periods were almost identical. Total cholesterol was 5.47 vs. 5.48 mmol/ L (212 vs. 212 mg/dL), LDL-C was 3.41 vs. 3.40 mmol/L (132 vs. 131 mg/ dL), HDL-C was 1.52 vs. 1.52 mmol/L (59 vs. 59 mg/dL), and TG were 1.17 vs. 1.20 mmol/L (104 vs. 106 mg/dL) for the caffeinated vs decaffeinated coffee periods, respectively. Further, a small study of 12 Finnish men also failed to find an effect of caffeinated coffee on serum cholesterol levels.15 However, the study period was only three weeks which may have been insufficient. 

The results of these studies, when considered together and with the observational studies reviewed above, suggest that any significant effect of coffee on serum cholesterol levels is likely due to something other than caffeine content. 

Forde et al.20 used a more complex study design to examine the effect of boiled coffee vs. paper-filtered coffee vs. coffee abstinence. The investigation involved 33 men with elevated baseline serum cholesterol levels (average 8.7 mmol/L [335 mg/dL]) who apparently were habitual boiled coffee drinkers (implied but not stated). The 10-week study was divided into two 5-week periods. Subjects were assigned to one of four groups (1) continuation of habitual consumption (control), (2) abstinence from coffee for the full 10 weeks, (3) abstinence from coffee for the first 5-weeks, followed by 5 weeks of paper-filtered coffee consumption, and (4) abstinence from coffee for the first 5 weeks, followed by 5 weeks of boiled coffee consumption. 

Among the nine men who continued their habitual coffee intake for the 10 weeks, serum cholesterol levels increased from 8.48 mmol/L (329 mg/dL) to 8.83 mmol/L (341 mg/dL). For the eight men in the second... 

Evidence from the studies above suggest that boiled (i.e., non-filtered) coffee contains a factor that raises serum cholesterol levels, whereas filtered coffee does not appear to induce a significant change in serum cholesterol. There are numerous chemical compounds in coffee that may help explain the effect of boiled coffee on serum cholesterol. Weusten-Van der Wouw et al.24 attempted to isolate such potential factors through a series of experiments. The first in this series, described above, showed that boiled coffee compared to boiled coffee that was subsequently also paper-filtered had an adverse effect on serum cholesterol levels.22... 

These studies suggest that at least four weeks are needed before maximum changes in serum cholesterol levels, resulting from coffee consumption or cessation, are likely to be achieved. 

Summary of Clinical Trials on Coffee Consumption and Serum Cholesterol Levels... 

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