Name the antioxidant vitamins and describe how they function in the body
Antioxidant vitamins include vitamin C, vitamin E, and beta-carotene. Antioxidants are compounds that protect other compounds (such as lipids in cell membranes) from attack by oxygen. Oxygen triggers the formation of compounds known as free radicals that can start chain reactions in cell membranes. Vitamin E and beta-carotene protect fat-soluble substances from oxidizing agents; vitamin C protects water-soluble substances the same way. By being oxidized itself, vitamin C regenerates already-oxidized substances such as iron and copper to their original, active form. In the intestines, it protects iron from oxidation and so enhances iron absorption. In the cells and body fluids, it helps to protect other molecules, including the fat-soluble compounds vitamin A, vitamin E, and the polyunsaturated fatty acids.
Like beta-carotene, vitamin E is a fat-soluble antioxidant. It protects other substances from oxidation by being oxidized itself. If there is plenty of vitamin E in the membranes of cells exposed to an oxidant, chances are this vitamin will take the brunt of any oxidative attack, protecting the lipids and other vulnerable components of the membranes. Vitamin E is especially effective in preventing the oxidation of the polyunsaturated fatty acids (PUFA), but it protects all other lipids (for example, vitamin A) as well.
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Dietaryguidance tends to focus on eating patterns and on disease risk reduction and quality of life enhancements.
Answer the following statement true (T) or false (F)
The most significant effects of long-term hunger on children include:
a. behavioral problems.
b. poor performance in school.
c. apathetic attitude.
d. impaired growth.
Bile is released into the ________ in response to the ingestion of fat
A) large intestine B) pancreas C) stomach D) small intestine
Explain the factors involved in the promotion of obesity by high-fat diets and food portion sizes