Vitamin Types and FunctionEach
vitamin has specific functions. If levels of a particular vitamin are
inadequate, a deficiency disease results. A good source for natural vitamins
are
Whole Food Vitamins
All Natural Vitamins.
Vitamin A helps in the formation and maintenance of healthy teeth,
skeletal and soft tissue, mucous membranes, and skin. It is also known as
retinol because it generates the pigments that are necessary for the working
of the
retina. It promotes good vision, especially in dim light. Vitamin A may
also be required for reproduction and breast-feeding. Beta-carotene is a
precursor to vitamin A that has antioxidant properties, helping the body
deal with unstable chemicals called free radicals.
Thiamine (B-1) helps the body cells convert
carbohydrates into energy. It is also essential for the functioning of
the heart and for healthy nerve cells, including those in the brain.
Riboflavin (B-2) works with the other B vitamins and is important for
body growth and red blood cell production. Similar to thiamine, it helps in
releasing energy from carbohydrates.
Niacin is a B vitamin that helps maintain healthy skin and nerves. It is
also important for the conversion of food to energy and may have
cholesterol-lowering effects.
Vitamin B-6 is also known as pyridoxine. The more
protein a person eats, the more vitamin B-6 is required to help the body
use the protein. It aids in the formation of red blood cells and in the
maintenance of normal brain function. It also assists in the synthesizing of
antibodies in the immune system.
Vitamin B-12, like the other B vitamins, is important for metabolism.
It, too, helps in the formation of red blood cells and in the maintenance of
the
central nervous system.
Pantothenic acid is essential for the metabolism of food. It is also
essential in the synthesis of hormones and
cholesterol.
Biotin is essential for the metabolism of proteins and carbohydrates,
and in the synthesis of hormones and cholesterol. Cholesterol is needed for
the functioning of cell membranes, particularly in the brain.
Folate (folic acid) works with vitamin B-12 in the production of red
blood cells. It is necessary for the synthesis of DNA, which controls
heredity as well as tissue growth and cell function. Any woman who may
become pregnant should be sure to consume enough folate -- low levels of
this substance are associated with devastating birth defects such as
spina bifida. Many foods are now fortified with folic acid to help
reduce the level of such birth defects.
Vitamin C, also called ascorbic acid, promotes healthy teeth and gums,
helps in the absorption of iron, and helps maintain normal connective
tissue. It also promotes wound healing and is an antioxidant.
Vitamin D is also known as the "sunshine vitamin," since it is
manufactured by the body after being exposed to sunshine. Ten to 15 minutes
of sunshine three times per week is adequate to produce the body's
requirement of vitamin D. This vitamin promotes the body's absorption of
calcium, which is essential for the normal development and maintenance of
healthy teeth and bones. It also helps maintain adequate blood levels of
calcium and
phosphorus, which are minerals necessary for many functions.
Vitamin E is also known as tocopherol and is an antioxidant. It is also
important in the formation of red blood cells and the use of vitamin K.
Vitamin K is known as the clotting vitamin, because without it blood
would not coagulate. Some studies indicate that it helps in maintaining
strong bones in the elderly.
Food
Sources
There
are 13 vitamins essential for bodily functions: Vitamins A, C, D, E, K, and
the B vitamins (thiamine,
riboflavin,
niacin,
pantothenic acid,
biotin,
vitamin B-6,
vitamin B-12, and folate). They all can be obtained from food, and
vitamin D and
vitamin K can be synthesized by the body.
FAT-SOLUBLE VITAMINS
Vitamin A is found in milk, cheese, cream, liver, kidney, and cod and
halibut fish oils. Because most of these sources are high in
saturated fat and cholesterol, vegetable sources of a vitamin A
precursor called beta-carotene may be a better choice. Beta-carotene comes
from carrots, pumpkin, sweet potatoes, winter squashes, cantaloupe, pink
grapefruit, apricots, broccoli, and spinach. The more intense the color of a
fruit or vegetable, the higher the beta-carotene content.
Vitamin D is found in cheese, butter, margarine, cream, fish, oysters,
and fortified milk and cereals. The body can also synthesize vitamin D when
the skin is exposed to sunshine.
Vitamin E is found in wheat germ, corn, nuts, seeds, olives, spinach,
asparagus, and other green leafy vegetables, vegetable oils, and products
made from vegetable oils, such as margarine.
Vitamin K is found in cabbage, cauliflower, spinach, soybeans, and
cereals. Bacteria in the intestines normally also produce vitamin K.
WATER-SOLUBLE VITAMINS
Thiamine (vitamin B-1) is found in fortified breads, cereals, pasta,
whole grains, lean meats, fish, dried beans, peas, and soybeans. Dairy
products, fruits, and vegetables contain some thiamine as well.
Niacin (vitamin B-3) is found in dairy products, poultry, fish, lean
meats, nuts, and eggs. Legumes and enriched breads and cereals also supply
some niacin.
Folate is found in green, leafy vegetables and many foods are now
fortified with it as well.
Vitamin B-12 is found in eggs, meat, poultry, shellfish, milk and milk
products.
Pantothenic acid and biotin are found in eggs, fish, dairy products,
whole-grain cereals, legumes, yeast, broccoli and other vegetables in the
cabbage family, white and sweet potatoes, lean beef, and other foods.
Vitamin C (ascorbic acid) is found in citrus fruits and their juices,
strawberries, tomatoes, broccoli, turnip greens and other greens, sweet and
white potatoes, and cantaloupe. Most other fruits and vegetables contain
some vitamin C; fish and milk contain small amounts.
|
|
