Page 248 - The Miracle in the Cell Membrane

The Miracle in the Cell Membrane

The Selection of Vitamins in the Body
Vitamins, which cannot be produced in the body's
cells, are organic compounds necessary in small quanti-
ties for normal metabolism of the body. An absence of
vitamins in the foods you eat may cause metabolism
defects. Vitamins are very important for healthy devel-
opment, digestion functions, and immunity to infections.
They also permit the use of carbohydrate, fat and protein
in the body.
Vitamins are not digested or burned up in the body.
Energy in the form of calories cannot be taken from them
directly. The body ensures that there is exactly the right
amount of each vitamin in the bloodstream. Surplus
water-soluble vitamins are expelled from the body in
urine, and surplus fat-soluble vitamins are stored in fatty
tissue, where excessive doses of these vitamins may be
harmful. Vitamins are stored in small quantities in all
cells, and some vitamins are stored in large quantities in
the liver. Special care must be taken with Vitamins A and
D in particular. The liver's store of Vitamin A, for exam-
ple, can last someone who consumes no vitamins for five
to ten months, and the liver's store of Vitamin D can gen-
erally last for two to four months.
The storage in the body of water-soluble vitamins is
relatively low. This is true of most vitamins, especially
Vitamin B. Symptoms of a lack of B complex vitamins
appear within a few days. This does not apply to Vitamin
B12 because the amounts stored in the liver can last a per-
son for a year or more. A lack of Vitamin C, another

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