Fats in nutrition

Investigation of the relationship of diet to blood lipids and atherosclerosis has dominated the field of lipid nutritional biochemistry for the past 25 years. Although this subject has consumed considerable time, effort, and research funds, it has also proved beneficial to other areas of lipid biochemistry by attracting qualified people to the field and by initiating development of sophisticated methodology and instrumentation required for progress in those areas. The development of capillary gas-liquid chromatography and high-performance liquid chromatography, together with more extensive computer control and processing of data, should accelerate progress in all areas of lipid biochemistry. In the next 25 years, I expect to see extensive investigation of dietary hydrogenated fats and their constituent isomeric fatty acids. Specificity of deposition in animal tissues, effects on blood lipids and coronary heart disease, and their relationship to polyunsaturated fatty acids and prostaglandins are among the topics likely to receive attention. The prostaglandins, prostacyclins, thromboxanes, and leukotrienes will continue to receive attention in the near future, and the role of diet in modulating the concentrations of these compounds in blood and other body tissues is a promising area of active research. The discovery of abnormalities in polyunsaturated fatty acid metabolism in pathological conditions in man has renewed interest in these dietary components. Association of neurological abnormalities with lack of linolenic acid metabolites should stimulate further investigation of the role of the n-3 series acids in central nervous system function.     

Boron in human and animal nutrition

This review describes the findings from human and animal studies indicating that B is a dynamic trace element which, in physiological amounts, can affect the metabolism or utilisation of numerous other substances involved in life processes including macrominerals, energy substrates such as triglycerides and glucose, nitrogen containing substances such as amino acids and proteins, reactive oxygen species, and estrogen. Through these effects, B can affect the function or composition of several body systems, including the brain, skeleton and immune system, generally in a beneficial fashion. Moreover, homeostatic mechanisms apparently exist for B because it is rapidly excreted in the urine, does not accumulate in tissues, and is maintained in a relatively narrow range of concentrations in blood of healthy individuals. Thus, even though B has not been conclusively established as essential because a biochemical function for it has not been identified, its beneficial actions suggest that an intake of over 1 mg day^-1 (but probably not more than 13 mg day^-1) is desirable; diets low in fruits, vegetables, legumes and nuts may not provide this amount of B. Boron may be of more practical nutritional importance than currently acknowledged.     

Drugs and nutrition in old age

Drug effects are influenced by physiologic and pathologic changes that occur as a consequence of aging. The elderly may be more disposed to drug-induced nutrient depletion because of chronic illness, inadequate diet and long-term drug use. Digoxin, isoniazid, corticosteroids, diuretics and psychoactive agents pose special hazards to the nutritional status of elderly patients. On the other hand, dietary factors, such as protein levels or vitamin deficiencies, may be important determinants of age-related changes in drug disposition or toxicity.