Serum Cholesterol in Man: Diet Fat and Intrinsic Responsiveness

Abstract

Data obtained froni a nutaiber of dietary experiments in mtm yield a formuht by which the responlses in serumI cholesterol to changes in diet can be predicted. In this paiiel. the reliability of this foralula is tested and the effects of various types of fatty acids Onl seruill cholesterol are investigated.THE serum cholesterol concentration in mani is strongly influenced by both the amount aiid kind of fat in the diet and it is necessary to differentiate between at least 3 classes of fatty aci(ls, saturatedl, molloelloi(, and poly-eiioic. Furthermore, even on a fixed dliet there are intrinsic differences between individuals. Finally, intraindividual variability is substantial as shown by spontaneous day-to-day variations. All these factors complicate the evaluation of the effects of the diet aiid the prediction of serum cholesterol responses to given dietary changes. However, the present paper will show that the average cholesterol responses of groups of miiein to changes of fat in the diet can be satisfactorily, predicted from knowledge of the amounts of fat in the diet and that such prediction can be made even for groups of men who are relatively hypercholesteremic or hypocholesteremic. Pre imrinary eIredictioni from 41 Sets of DatlAs a first ap)roximation we proposed1 that the serum total cholesterol concentration be expressed as C/ol. = k + bS + cl/ + (diP (1) where k refers to all factors, other than the fats in the diet, that influence the cholesterol Front the Laboratory of Physiological 1ys gielee, University of M-inniesota, and the Hastinags State Hospital, Minn.

Nutrigenomics, the Microbiome, and Gene-Environment Interactions: New Directions in Cardiovascular Disease Research, Prevention, and Treatment

“…7 These conclusions were supported by small short-term human feeding studies designed to show that replacement of carbohydrate or polyunsaturated fatty acids (PUFAs) with saturated fatty acids (SFAs) increased total cholesterol. 8 A growing evidence base that includes millions of participants who have provided detailed dietary and lifestyle data and biological specimens has shaped our understanding of biological pathways for micronutrient and macronutrient metabolism and their effects on disease. Findings from these efforts serve as the foundation for the evolution of contemporary dietary guidelines, 9 which are refined as new technologies and methods permit ever more rigorous standards for defining optimal nutritional guidelines.…”

Metabolic Changes in Healthy Men Using Fat-Modified Diets

“…The significantly better lowering effect on serum total and LDL cholesterol of the diet using corn oil as the predominant fat (ta ble II) bears out the initial hypothesis of the experiment which was based on the observa tions of other investigators [12,13]. A differ ence of 6.8% in the concentration of serum cholesterol may seem small and of little prac tical consequence.…”

“…In particular, the change in endogenous sterol excretion appeared to depend mainly on the magni tude of change in serum cholesterol, and not on the type of fat used. It has been suggested that the higher content of tocopherols and ubiquinones in germ oils may lower serum cholesterol in addition to the effect of the fatty acids [12,13,30,31], It is conceivable that these compounds could enhance the ac tion of polyunsaturated fatty acids in the body by protecting them against oxidation [32].…”

“…It was one of the aims of the experiment to com pare the efficacy of two commonly used oils with high linoleic acid content, sunflower oil and corn oil. The purpose here was to test previous reports of a better serum cholester ol-lowering effect of corn oil than was to be expected from the fatty acid composition alone [12,13]. The assumption of previous investigators has been that the high content of unsaponifiable matter of the oil, mostly phytosterols, tocopherols and ubiquinones, may be responsible.…”

Unresolved problems in the diet-heart issue.

“…Dietary effects on LDL were reviewed by Grundy. 21 There is now evidence which suggests that HDL cholesterol, previously thought to be unaffected by diet, 22 may be influenced along with LDL cholesterol by some dietary components.…”