Vitamin damage from radicals

Radicals control the chemistry of the upper atmosphere, where they contribute to the formation and decomposition of ozone. Radicals also play a role in our daily lives, sometimes a destructive one. They are responsible for the rancidity of foods and the degradation of plastics in sunlight. Damage from radicals can be delayed by an additive called an antioxidant, which reacts rapidly with radicals before the radicals have a chance to do their damage. It is believed that human aging is partly due to the action of radicals, and antioxidants such as vitamins C and E may delay the process (see Box 2.1). 

Ascorbic acid—vitamin C—is an essential nutrient that the human body cannot manufacture from other compounds. It is needed for the formation of collagen, the protein that makes up connective tissue, and is essential to muscles, bones, cartilage, and blood vessels. It is a strong antioxidant, preventing damage from oxygen free radicals. 

Most of the other medications studied to slow the course of Alzheimer s dementia presumably work as an antioxidant to protect nerve cells from damaging free radicals. Of the antioxidants, vitamin E is the safest and has the best evidence of efficacy. Thus, we recommend that all patients receive 2000 lU of vitamin E each day during... 

A variety of antioxidants are added to food including vitamin C and vitamin E. Two antioxidants that may occasionally cause problems are butylated hydroxytoluene (BHT) and butylated hydroxyanisole (BHA), which have been associated with symptoms such as eczema, skin rash, runny nose, wheezing, headache, chest pain, flushing of the skin, and red eyes. At the same time, it has been reported that these antioxidants may be helpful in preventing cancer, possibly by removing damaging free radicals such as reactive oxygen and its by-products from fatty acids. 

Rachitic rosaiy, 582 RAC protein, 905 Radicals damage from ascorbic acid and, 626 vitamin E, 631,632 forrnation, 829... 

Vitamins are defined as a biologically active group of organic compounds that have a relatively low molecular weight. They are minor, but essential for an organism s normal health and growth. Humans need to obtain them from food or supplements [1,2]. These nutrients facilitate the metabolism of proteins, carbohydrates, and fats. They are reported to reduce damage from free radicals [3], and insufficient levels may result in deficiency diseases [4]. 

In cancer research, vitamin C has received particular attention because of the antioxidant hypothesis. It is hypothesized that vitamin C scavenges radicals which otherwise would damage DNA or other cell-regulating structures. Particular attention has been given to vitamin C in relation to the formation of N-nitroso compounds (Mirvish, 1986). N-nitroso compounds are formed from nitrite and amines. Some of them are powerful carcinogens and often applied in animal experiments, particularly in stomach cancer studies. The relationship of vitamin C intake to risk for total cancer was analyzed in several prospective studies. In contrast to Kromhout (1987), a study by Heilbrun et al. (1989) found a significant reduction of risk for total cancer. 

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