Dietary supplements chronic diseases

Section 13 of the Dietary Supplement Health and Education Act of 1994 created an Office of Dietary Supplements as part of the National Institutes of Health. The office was given two primary responsibilities (1) to explore more fully the potential role of dietary supplements as a significant part of the efforts of the United States to improve health care and (2) to promote scientific study of the benefits of dietary supplements in maintaining health and preventing chronic disease and other health-related conditions. 

Reference Intakes (DRIs). In the past, the recommended dietary allowances (RDAs), which are the levels of intake of essential nutrients that are considered to be adequate to meet the known nutritional needs of practically all healthy persons, were the primary reference value for vitamins and other nutrients. The DRIs also include other reference values, such as the estimated average requirement (EAR) and the adequate intake (AI). The RDA, EAR, and AI reference standards define nutritional intake adequacy. Since these recommendations are given for healthy populations in general and not for individuals, special problems, such as premature birth, inherited metabolic disorders, infections, chronic disease, and use of medications, are not covered by the requirements. Separate RDAs have been developed for pregnant and lactating women. Vitamin supplementation may be required by patients with special conditions and for those who do not consume an appropriate diet. 

Coenzyme QIO is a powerful antioxidant naturally occurring in the mitochondria of myocardium, and it is an electron carrier in the mitochondrial synthesis of ATP. Patients with heart failure have lower myocardial levels of coenzyme QIO, but supplementation has been demonstrated to have variable benefits in randomized controlled trials. One meta-analysis on the use in congestive heart failure showed improvements in stroke volume, ejection fraction, cardiac output, cardiac index, and end diastolic volume index. " Another antioxidant associated with beneficial effects in cardiac patients is lycopene, a natural constituent of tomatoes. Lycopene is the major carotenoid found in human serum, and epidemiological studies have indicated an effect of dietary supplementation in reducing heart disease. Few dietary interventions have been reported one study showed a mild but significant hypocholesterolemic effect, and another showed a significant reduction in LDL oxidation. " Animal studies show an antiatherogenic effect of DHEA, and a review of the clinical trials and studies on DHEA in males with coronary heart disease reported a favorable or neutral effect. Plasma levels of DHEA are decreased in patients with chronic heart failure in proportion to its severity. ... 

Free radical damage is considered to be a causative factor in the development of cancer and inflammatory and chronic diseases. Therefore, free radical scavenging molecules (antioxidants) may play a beneficial role in these conditions. With repect to CVD, the oxidation of low-density lipoprotein (LDL) is believed to be a critical process in the development of atherosclerosis (Berliner et al., 1995 Navab et al., 1995). The presence of oxidized LDL in the intima of an artery leads to the production of macrophage-derived foam cells, the main cell type present in fatty streaks that are believed to be the earliest lesion of atherosclerosis (Fuster, 1994). Therefore, the use of antioxidants as dietary supplements to protect against LDL oxidation may reduce both the development and progression of atherosclerosis (Gey, 1995). 

In livestock, concern for selenium toxicity and deficiency is high. In areas of the country with selenium-poor soils, dietary selenium supplementation for livestock has been necessary to prevent chronic selenium deficiency diseases. Dietary supplementation programs have resulted in cases of accidental poisonings from misuse of the selenium supplements (Hopper et al. 1985). 

Uses Dietary supplement to treat diseases of the blood vessels and lymph system, incl. hemorrhoids, chronic venous insufficiency, easy bruising, nose bleeds, lymphedema aids absorp. and use of Vitamin C reputed to help reduce cholesterol levels, control inflammation, benefit individuals with diabetes, reduce allergic reactions, and prevent cancer Manuf/Distiib. Acros Org. http //www.acros.be Hesperidinase... 

A chitosan-based nutritional supplement (Epakitin , Vdtoquinol) that is claimed to bind phosphate and reduce urea levels is commercially available for use in chronic kidney disease in dogs and cats (Vetoquinol Web site 2009). There are commercially available dietary supplements containing chitosan that can be directly sprayed on the food for the dogs (Exotic Dogs Web site 2009). Food applications of chitin and chitosan are currently limited. 

Iron deficiency is commonly caused by insufficient dietary intake, excessive menstrual flow, multiple births, and gastrointestinal bleeding (occult or patent) due to medications (aspirin, steroids), hiatal hernia, peptic ulcers, gastritis associated with alcoholism, anemia of chronic disease, geophagia, and tumors. After these patients are carefully diagnosed, iron supplementation is administered using oral ferrous sulfate or by intravenous therapy with an iron-dextran complex (Imferon) [28,29]. 

Vitamin B12 must be converted into its coenzyme forms, adenosylcobalamin and methylcobalamin, in the cell. These coenzymes function as cofactors of methylmalonyl-CoA mutase and methionine synthase, respectively. Chronic kidney disease (CKD) may affect the conversion from vitamin B12 to the coenzyme forms. This section describes the intracellular metabolism of cyanocobalamin, which is included in many dietary supplements, in particular, referring to a recently discovered trafficking chaperone called methylmalonic aciduria cdlC type with homocystinuria (MMACHC). Cyanocobalamin is first converted to cob(II)alamin, which has no cyanogen group on the ligand occupying the upper axial position of the cobalamin structure. Cob(II)alamin is further reduced to cob(I)alamin, which can function as a coenzyme in the body. 

Fig. 4 Structures of phytochemical components in dietary supplements undergoing evaluation of benefits in chronic diseases (+)-catechin (a flavanol), quercetin (a flavonol), resveratrol (a stilbenoid), lycopene (a carotenoid), genistein (an isoflavone) and puerarin and daidzin (8-C- and 7-O-glucosides of the isoflavone daidzein). They are each drawn so that the A ring is in the same orientation...

Regulatory Status. Class 1 dietary supplement (can be safely consumed when used appropriately). Milk thistle is the subject of a positive German therapeutic monograph indicated for toxic liver damage, liver cirrhosis, and supportive treatment of chronic inflammatory liver disease. ... 

The occurrence of dietary polyphenols in largely consumed vegetables and their bioavailability need to be known for a proper evaluation of their potential health benefits. In the past years many studies on the uptake and the metabolism of dietary polyphenols have been published, and presently a better information on the absorption and fate of polyphenols from regular food, beverages and supplements is available. By contrast, the polyphenol content of different vegetables consumed in large amounts and with beneficial properties is still poorly defined. This is the case of tomatoes, which represent an important part of the mediterranean diet and are thought to diminish the risk of certain chronic diseases (72, 73). 

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