Cholesterol content of food

Nutritional understanding of the effect of fats in the diet has made considerable progress.26-30 It was understood that saturated fats (see Chapter 3, Section 3.8) were the least beneficial as they raised serum cholesterol. High serum cholesterol is now associated with heart attacks and strokes. There was for this reason pressure over the cholesterol content of foods. This pressure has now been relieved since it appears that dietary cholesterol is not a particularly serious issue. The human body makes cholesterol, so dietary cholesterol does not necessarily affect serum cholesterol level as dietary intake can be compensated for by reduced cholesterol synthesis. 

Nutrient claims for fat, fatty acid, and cholesterol content of foods... 

Data from R, M. Feeley el al. (1972). Cholesterol content of foods. Journal of the American Dietitians Association, 61,134-149... 

Mean dietary cholesterol levels declined from the 1970s to 1988-1994, leveling off between 1988-1994 and 1999-2000. For adults aged 20 to 74, mean dietary cholesterol intake decreased from 487 to 341 mg in men and 313 to 242 mg in women. Possible reasons for this decrease include improved measurements of the cholesterol content of foods and a decreased consumption of whole eggs. ... 

Analysis of vitamin content of food materials appears to be a developing field. B vitamins in rice were analyzed using a mobile phase which contained pentanesulfonic acid and heptanesulfonic acid (558). Although the peaks were not sharp, the separation of the vitamins was satisfactory. Vitamin D in fortified milk has b n analyzed after removal Of cholesterol and carotenes in a preliminary cleanup (559, 540). Vitamin A has been analyzed in margarine, infant formula, and fortified milk (541, 542). Reports of the analysis of other vitamins in food are few to te but this mode of analysis can be expected to rapidly expand in the future in light of the variety of vitamin determinations in formulations which have been done (see Section VIII,F,l). 

While many of the poorer people on earth starve to death the problems of atherosclerosis and obesity affect many in wealthier societies.2533-0 Tire fat content of foods is often blamed, and, as discussed in Boxes 21-B and 22-B, the quality of fatty acids in the diet is very important. However, like fatty acids, carbohydrates are also metabolized via acetyl-CoA and can readily be converted to both fatty acids and cholesterol.2534 Obesity is largely a problem of excessive total caloric intake. 

HPLC determination (Osada et al., 1999), and HPLC/MS (Redden and Huang, 1991). In general, enzymatic determination is superior to colorimetry to obtain true cholesterol content. When food such as shellfish contains sterols other than cholesterol, the GC determination is the most adequate method. Although GC/MS also accomplishes good separation between and identification of all sterol analogs, the instrument is too expensive to use for routine analyses of cholesterol. 

King JW, Johnson JL, Orton WL, McKeith FK, O Connor PL, Novakofski J, Carr TR. Effect of supercritical carbon dioxide extraction on the fat and cholesterol content of beef patties. J Food Sci 1993 58 950-952, 958. 

Lange, W. 1950. Cholesterol, phytosterol and tocopherol content of food products and animal tissues. J. Am. Oil Chemists Soc. 27, 414. 

Kunsman, J.E., Collins, M.A., Field, R.A. and Miller, G.J. (1981) Cholesterol content of beef bone marrow and mechanically deboned meat. J. Food Sci. 46, 1785-1788. 

Elkin, R.G. and Rogler, J.C. (1990) Reduction of the cholesterol content of eggs by the oral administration of lovastatin to laying hens. J. Agric. Food Chem. 38, 1635-1641. 

Decreasing the intake of fats, especially animal fats (saturated fats), decreases the cholesterol level somewhat. The cholesterol content of eggs, however, may not be harmful. For most people even ten eggs per day does not raise the cholesterol concentration by more than a few percent. The other nutrient substances, such as the phospholipid lecithin, in this valuable food may assist in controlling the cholesterol. 

Table 18.2 Cholesterol content of commonly used foods (mg 100 edible portion)...

The amount of cholesterol synthesized in the body is partly regulated by the dietary intake. The cholesterol content of some commonly used foods is given in Table 18.2. In the West the average daily intake is 5(X)-8(X)mg, of which about 300-400 mg are absorbed in spite of its insolubility in water. One of the effects of dietary cholesterol is to inhibit HMG-CoA reductase. The absorbed cholesterol not only reduces the activity of the enzyme already present but also suppresses the synthesis of additional enzyme. Increases in plasma cholesterol have another important effect on cholesterol metabolism. Cells other than those of the liver and intestine obtain most of their cholesterol from the plasma and the cholesterol is carried to these tissues in the form of low-density lipoproteins (LDL). These complexes have apoprotein B as their main shell protein and this reacts with high-affinity receptors in the plasma membrane of... 

Table 3.39 Cholesterol content in foods of animal origin.

Table F-4, Fats Fatty Acids in Selected Foods, provides information on the total fat, animal fat, plant fat, saturated fat, polyunsaturated fat, oleic acid, linolenic acid, and cholesterol content of a variety of foods. As with any food composition data, the values contained in this table are not absolutes, but guidelines. They are meant to aid individuals who must or wish to alter or control their dietary fat intake.

The physiologic sequelae of biotin deficiency are almost unexplored. Severe skin lesions, especially seborrheic dermatitis and Leiner s disease (Erythroderma desquamativum or exfoliative dermatitis), were increased in young infants bom of mothers on a restricted diet low in eggs, livers, and other biotin-rich foods. After biotin administration the lesions healed. There are claims that excess biotin produces a fatty liver characterized by heightened cholesterol content. Choline has no effect in the prevention of biotin-fatty livers (G2, M2). In mice with transplanted tumors, both the tumors and the blood levels of biotin are below normal (R8). More recent studies established a protection with avidin, the biotin-binding fraction of egg white, against tumor formation (K4). More data along these lines are still needed for confirmation. 

Dairy foods are not particularly high in either total fat or cholesterol (Renner 1983). Moreover, a wide variety of dairy foods of varied fat and cholesterol content is available to meet consumer needs (Renner 1983). For example, individuals on fat-restricted diets can choose from such lowfat dairy foods as 2% milk, 1% milk, skim milk, lowfat yogurt,... 

United States regulations on nutrition labeling of foods require that cholesterol content be given and that it be analyzed by GC measurement as shown in the AOAC method, which uses a packed column (Lewis et al., 1996 AOAC, 1990). The reference value, which is a set of recommended nutrient intake levels of cholesterol, is defined as 300 mg. However, the Codex guideline does not request labeling of cholesterol. Cholesterol contents in some foods and foodstuffs determined by GC measurement are summarized in Table Dl.3.3. 

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