VITAMIN
D DEFICIENCY
Vitamin
D deficiency causes rickets in children, exacerbates osteoporosis and causes
osteomalacia in adults. Vitamin D must be taken with adequate amounts of both
calcium and magnesium supplementation. When calcium levels are low (due to
insufficient vitamin D and calcium intake), the body activates the parathyroid
gland, which produces PTH (parathyroid hormone). This hormone kick starts
vitamin D hormone production and assists removal of calcium from the bones to
be used in more important functions such as neutralizing body acidity.
NATURAL
SOURCES OF VITAMIN D
Very
few foods naturally contain vitamin D. Fatty fish such as salmon and cod,
vitamin D-fortified milk, cereals, and multivitamin supplements are the major
sources of vitamin D. The main source of vitamin D is the sun and in hot
climates such an intake is readily possible if an individual spends a
reasonable amount of time in the sun. However, in colder climates, like those
of Canada, northern USA and northwest Europe, it is almost impossible to
average 4,000 IU per day because for at least six months of the year, intake
from the sun is negligible at best. Even during the few hot summer months, an
individual would have to spend considerable time in the sun to achieve the
required intake.
DIETARY
FACTORS THAT AFFECT VITAMIN D LEVELS
Original
man's diet was dominated by fruits, vegetables, and lean wild meats which have
a low saturated fat content. The main foods introduced by agriculture are
grains, dairy products, and meat from domesticated animals which has a very
high saturated fat content.
Grains
contain phytate or phytic acid, which counters the action of vitamin D. The
only common grain with a very low phytate content is rice.
In
1991, studies showed that part of the bovine albumin protein or milk is a
molecular mimic of the vitamin D receptor. An immune reaction against that
milk protein can potentially result in an autoimmune reaction against the
vitamin D receptor, which would significantly lower the effectiveness of
vitamin D hormone to bind with a variety of cells, including immune
cells.
Proteins
from various foods introduced by the agricultural revolution (gluten, dairy,
legumes) result in autoimmune reactions by increasing intestinal permeability
and by mimicking infectious and self-antigens. The great increase in the
consumption of saturated fat also contributes to an increase in inflammatory
reactions. Food-driven autoimmune reactions occur almost on a daily basis.
They have a significant cumulative effect and result in harmless auto-immunity
becoming problematic autoimmune disease in genetically susceptible
people.
Alcohol
consumption also interferes with vitamin D metabolism.
VITAMIN
D TOXICITY
Vitamin
D toxicity effects include excessive absorption of calcium from the intestine
and resorption of calcium from bone. This results in deposits of calcium and
phosphorus in soft tissues all over the body, with particular damage to the
heart, blood vessels, and kidneys. 2,000 IU daily poisons children, and
especially sensitive children have been intoxicated with less than half of
that. Studies done in 1999 by R. Vieth shows that 10,000 IU/day produce no
observed adverse effects in adults and concluded that 10,000 IU/day is safe
(assuming no hypersensitivity exists).
HOW
TO TAKE VITAMIN D SUPPLEMENTS
Because
vitamin D is a fat-soluble vitamin, it is more effectively utilized when taken
in divided doses with fat-containing, low fiber meals.
VITAMIN
D REQUIREMENTS
Vitamin
D requirements depend on sun exposure, skin color, and dietary factors.
Recommendations range from 600 IU per day for adult Canadians to 400 IU for
Canadian infants. Treatment of vitamin D deficiency in adults can be corrected
by 50,000 IU of vitamin D once a week for 8 weeks followed by a multivitamin
containing 400 IU/day.
