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Diet and coronary heart disease: beyond dietary fats and low-density-lipoprotein cholesterol.

Fraser, G.E., 1994. Diet and coronary heart disease: beyond dietary fats and low-density-lipoprotein cholesterol. Am J Clin Nutr. 59(suppl):1117S-23S.

Traditionally, the effects of diet on coronary heart disease have been attributed to the effects of medium-chain fatty acids, soluble fiber, and dietary cholesterol on serum low-density-lipoprotein (LDL) cholesterol concentrations. We review evidence here that many other dietary substances may affect risk, often via mechanisms not involving LDL-cholesterol concentrations directly. Such substances include phytosterols, tocotrienols, arginine, and antioxidant vitamins. The effects of diet on high-density-lipoprotein-cholesterol concentrations, triglycerides (fasting and postprandial), oxidized LDL particles, prostaglandins, and endothelium-derived relaxing factor are described. Finally, an illustration of some epidemiologic associations between diet and coronary disease events is made from the Adventist Health Study data.

Partial replacement of saturated fatty acids with almonds or walnuts lowers total plasma cholesterol and low-density-lipoprotein cholesterol.

Abbey, M., M. Noakes, G.B. Belling, P.J. Nestel, 1994.  Partial replacement of saturated fatty acids with almonds or walnuts lowers total plasma cholesterol and low-density-lipoprotein cholesterol. Am J Clin Nutr. 59:995-9.

Sixteen normolipidemic male volunteers aged 41 +/- 9 y (mean +/- SD) consumed a diet providing 36% of energy as fat (92 g fat/d) for 9 wk. A daily supplement of nuts (providing half of the total fat intake) was provided against a common background diet. In the first 3-wk period the background diet was supplemented with raw peanuts (50 g/d), coconut cubes (40 g/d), and a coconut confectionary bar (50 g/d), designed to provide 47 g fat with a ratio of polyunsaturated to monounsaturated to saturated fatty acids (P:M:S) to match the Australian diet (reference diet). During the following 3 wk the background diet was supplemented with monounsaturated fatty acid-rich raw almonds (84 g/d), equivalent to 46 g fat, and during the final 3-wk period the background diet was supplemented with polyunsaturated fatty acid-rich walnuts (68 g/d), equivalent to 46 g fat. Compared with the reference diet there were significant reductions in total and LDL cholesterol, 7% and 10%, respectively, after supplementation with almonds, and 5% and 9%, respectively, after supplementation with walnuts.

Effects of a diet high in monounsaturated fat from almonds on plasma cholesterol and lipoproteins.

Spiller, G.A., D.J. Jenkins, L.N. Cragen, J.E. Gates, O. Bosella, K. Berra, C. Rudd, M. Stevenson, R. Superko, 1992.  Effects of a diet high in monounsaturated fat from almonds on plasma cholesterol and lipoproteins. J Am Coll Nutr 11(2):126-30.

The effect of almonds as part of a low saturated fat, low cholesterol, high-fiber diet was studied in 26 adults (13 men, 13 women). The baseline diet was modified in a similar way for all subjects by limiting meat, fatty fish, high-fat milk products, eggs, and saturated fat. Grains, beans, vegetables, fruit, and low-fat milk products were the foundation of the diet. During the almond diet period, raw almonds (100 mg/day) supplied 34 g/day of monounsaturated fatty acid (MUFA), 12 g/day of polyunsaturated fatty acid, and 6 g/day of saturated fatty acid. Almond oil was the only oil allowed for food preparation. There was a rapid and sustained reduction in low-density lipoprotein cholesterol without changes in high-density lipoprotein cholesterol. This was reflected in a total plasma cholesterol decrease from (means +/- SEM) 235 +/- 5.0 at baseline to 215 +/- 5.0 at 3 weeks, and to 214 +/- 5.0 mg/dl at 9 weeks (p less than 0.001). When the consumption of nuts high in MUFA increases the fat content of the diet, reduction rather than elevation of plasma cholesterol has to be expected, possibly due to the MUFA content of these nuts.

Solubilization, electorphoretic characterization and in vitro digestibility of almond (Prunus amygdalus) proteins.

Sathe, S.K., 1992. Solubilization, electorphoretic characterization and in vitro digestibility of almond (Prunus amygdalus) proteins. J Food Biochem. 16:249-64.

The major U.S. marketing varieties of almonds contained moisture, protein, fat, and ash in the range 4.35-5.86%, 16.42-22.17%, 53.59-56.05%, and 2.69-2.93%, respectively. Two fatty acids, oleic (range 52.44-67.07%) and linoleic (range 22.05-38.67%) accounted for up to 90% of the total fat. The majority of almond proteins (≥ 95%) are water soluble with a minimum solubility at pH ≤ 4.0. Sodium chloride (1.0 M) decreased the almond protein solubility in aqueous medium. Electrophoretic analyses indicated that one water soluble protein dominates the almond protein composition. This oligomeric major protein is made up of two kinds of polypeptides (molecular weight range 20,000-22,000 and 38,000-41,000) linked via disulfide bonds. Among the proteases tested, pepsin was the most efficient in hydrolyzing the almond proteins.