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Vitamin deficiency or excess may yield symptoms
of diminishing health such as goiter, scurvy, osteoporosis,
weak immune system, disorders of cell metabolism, certain forms of cancer, symptoms
of premature aging, and poor psychological
health.
About 70% of the non-fat mass of the human body is made of water. To function properly, the body
requires between one and seven liters of water per day to avoid dehydration;
the precise amount depends on the level of activity, temperature, humidity, and
other factors. With physical exertion and heat exposure, water loss will
increase and daily fluid needs may increase as well. Normally, about 20 percent of water intake
comes from food, while the rest comes from drinking water and beverages . Water is excreted from
the body in multiple forms; through urine
and feces, through sweating,
and by exhalation of water vapor in the breath.
Other micronutrients include antioxidants and phytochemicals.
Phytochemicals may act as antioxidants, but not all phytochemicals are antioxidants.
As cellular metabolism/energy production requires oxygen, potentially damaging compounds known as radical oxygen species or free radicals form as a result. For normal cellular maintenance, growth, and division, these free radicals must be sufficiently neutralized by antioxidant compounds, some produced by the body with adequate precursors (glutathione, Vitamin C in most animals) and those that the body cannot produce may only be obtained through the diet through direct sources (Vitamin C in humans, Vitamin A, Vitamin K) or produced by the body from other compounds (Beta-carotene converted to Vitamin A by the body, Vitamin D synthesized from cholesterol by sunlight). Phytochemicals and their subgroup polyphenols comprise of the majority of antioxidants, some 4,000 known, and therefore there is much overlap. Different antioxidants are now known to function in a cooperative network, e.g. vitamin C can reactivate free radical-containing glutathione or vitamin E by accepting the free radical itself, and so on. Some antioxidants are more effective than others at neutralizing different free radicals. Some cannot neutralize certain free radicals. Some cannot be present in certain areas of free radical development (Vitamin A is fat-soluble and protects fat areas; Vitamin C is water soluble and protects those areas). When interacting with a free radical, some antioxidants produce a different free radical compound that is less dangerous or more dangerous than the previous compound. These nutrients aretypically found in edible plants, especially colorful fruits and vegetables, but also other organisms including seafood, algae, and fungi. The effects of phytochemicals increasingly survive rigorous testing by prominent health organizations. One of the principal classes of phytochemicals is polyphenol antioxidants, chemicals which are known to provide certain health benefits to the cardiovascular system and immune system. These chemicals are known to down-regulate the formation of reactive oxygen species, key chemicals in cardiovascular disease.
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