No abstract

This paper reviews epidemiological studies on the relationship between diet and high density lipoproteins (HDL), with emphasis on the authors' studies of boys and men from different countries and with different dietary habits. Sera were collected from boys (ages 7 to 9 years) and men (ages 33 to 48 years) in 20 countries, and these were analyzed in one standardized laboratory. In boys, total and HDL cholesterol changed in parallel, from low values in populations in developing countries with low-fat, high-carbohydrate diets to high values in affluent populations. The correlation between HDL and total cholesterol was 0.90 (n = 16 populations). A similar trend was seen in groups of vegetarian and omnivorous boys within one region. Detailed analyses of individual diets of boys in five countries showed a negative relation between carbohydrate intake and HDL cholesterol both for group means (r = -0.99, n = 5) and for individual boys within one country (r = -0.26 to 0.04, n = 109 to 133 boys per country). In these boys, differences in obesity and physical activity were slight, and unrelated to differences in HDL. Total cholesterol rose with saturated fat intake (r = 0.87 for five population means; r = 0.07 to 0.26 within population groups). In adult men, total and HDL cholesterol also tended to rise simultaneously with affluence. However, the relation was much weaker (r = 0.60, n = 13 population groups).(ABSTRACT TRUNCATED AT 250 WORDS)

In the period 1963-1974, 82 monks and 48 nuns from five Dutch and Belgian Trappist monasteries each participated in two or more out of nine different trials designed to test the effect of 58 different fat-modified diets on serum cholesterol. We analysed these data to quantify the extent to which healthy, normolipaemic subjects differ in the responsiveness of their serum cholesterol to a change in dietary fatty acid composition. Statistically significant between-person variance components (SD2p) were found in the serum cholesterol responses for the whole group (SD2p = [0.20 mmol l-1]2), for the men (SD2p = [0.24 mmol l-1]2) and for those women who participated in three or more trials (SD2p = [0.14 mmol l-1]2). The between-person variation (expressed as SD) was on average only half as large as the within-person variation in response when the same subject was challenged repeatedly. It is concluded that medically significant differences in responsiveness to fat-modified diets exist in both men and women. However, few subjects fail entirely to respond to a change in dietary fatty acid composition. In addition, the large within-subject variability makes it difficult to identify hypo- and hyperresponders.

To find out whether the consumption oflecithin has a more beneficial effect

We studied intra-individual variation in total and high-density lipoprotein (HDL) cholesterol in healthy volunteers (22 men and 19 women, ages 19 to 62 years) on controlled natural diets. The within-person coefficient of variation (CV) depended on the interval between blood samples, increasing from about 2% to 3% for measurements made 24 h apart to 4% to 5% for measurements made at four-day intervals or longer. We conclude that within-subject fluctuations in total and HDL cholesterol have a time constant of several days. Multiple measurements are generally needed to decide whether an asymptomatic subject exceeds a certain concentration of total or HDL cholesterol; we recommend that such measurements be made at least four days apart.