Vitamin D Pills
Are of Little or No Benefit and Some Harm. So What to Do Now?
According to popular opinions coming from
friends, family, and physicians, most people are vitamin D deficient and
in need of supplementation with pills. Evidence suggests that more than
40% of the world's population is vitamin D deficient (1). A recent
report from a Scottish doctor found only 2% of his patients had a
sufficient vitamin D concentration (75 nmol/L or above), and 47% had a
severe deficiency (below 25 nmol/L) (2). Low vitamin D levels found in
the blood are a clear indication that there is a worldwide problem of
sunlight deficiency. Rather than correct the problem and encourage
people to expose themselves to more of this natural element, the
solution has become another drug —
a supplement pill sold as vitamin D.
According to the authors of a landmark
editorial just published in the March 2, 2010 issue of the Annals of
Internal Medicine, "Despite the promise for disease prevention
suggested by available studies, we believe that the evidence for
widespread use of high-dose vitamin D supplementation in the general
population remains insufficient (3)." Even though the supplements
translate into higher levels of vitamin D in the blood, expected
benefits of reductions in the occurrences of common diseases are
lacking.
Recent vitamin frenzies over the
recommendations for the widespread use of antioxidants, folic acid,
vitamin E, and beta-carotene provide lessons about vitamin supplements
that must not be forgotten. When the proper research was finally done,
the results backfired. More heart disease, cancer, and overall death
were discovered in those taking these isolated concentrated nutrients
(4-9). Each of the above nutrients is originally found in edible plants.
In these perfect packages these nutrients provide for excellent health,
prevent and cure diseases, and prolong life.
When consumed as isolated concentrated
nutrients wrapped in a pill-casing, vitamin D supplements cause
nutritional imbalances, which leads to metabolic sicknesses. At dosages
considered safe, an increase in "bad" LDL-cholesterol, prostate cancer,
immune system suppression, autoimmune diseases, gastrointestinal
symptoms, kidney disease, and calcium stones has been observed
(10-16). The adverse effects of vitamin D therapy are understudied,
underestimated, and underreported.
Confounding
Factors Inflate the Benefits of Vitamin D
A serious metabolic and bone disease,
known as rickets, is the classic example of the consequences of
prolonged sunlight deficiency. Ultraviolet light in the spectrum of the
sun and vitamin D supplements will cure this condition. No one argues
about this.
Recently, low vitamin D status has been
associated with many other illnesses, such as heart disease, strokes,
type-2 diabetes, common cancers (breast, prostate, and colon), and
multiple sclerosis. The original evidence for this connection is the
observation that people who live farther away from the Equator (north
and south) experience a greater risk of developing these common
diseases. This risk is blamed on a lessening of the amount of sunshine
received annually by various populations. But a crucial oversight is
made: as people move further away from the Equator they eat fewer plant
foods and more animal foods. Sunshine plays a big part in overall
health, but a small part in the prevention of common Western diseases.
It's the food!
Researchers are further confused by
confounding factors, such as: people with higher vitamin D status are in
general of a young age, normal body weight, and live a healthy lifestyle
(17). Lower vitamin D status is associated with smoking, parental
history of myocardial infarction, alcohol intake and suffering with
chronic illnesses (17). Health-conscious people are more likely to
consume vitamin D fortified low-fat milk and fish (a vitamin D source),
as opposed to soft drinks and junk foods, favorites of unhealthy people.
(Yes, neither milk nor fish is a healthy food, but they serve as markers
of people who have better habits.)
The Benefits
from Pills Remain Unproven
Even though there is an association
between lower vitamin D status and heart disease, strokes, type-2
diabetes, common cancers (breast, prostate, and colon), and multiple
sclerosis, treatments with supplements have not been shown to be
effective for these conditions (17-19). The benefits for bone fracture
prevention are small and largely restricted to institutionalized elderly
women and to studies that use a combination of vitamin D and calcium,
not vitamin D alone (17,19).
Vitamin D Testing
Laboratory tests to check for vitamin D status usually measure
the 25-hydroxy vitamin D,
25(OH)D, form in nmol/L
Deficiency: 25 or less
Insufficiency: 50 or less
Sufficiency: 51 to 75
Safe range: below 140
Toxicity: 750
Researchers do not report 25(OH)D units in consistent ways. To
convert ng/mL to nmol/L multiply by 2.496. |
Sunlight is the
Best Way to Raise Vitamin D Levels in the Body
Sunlight, in UVB wavelengths of 290 to
315 nm, is the natural and most effective way to produce vitamin D in
the body, and an estimated 90% of our daily body requirements are met by
sunlight exposure (20,21). In the summertime, exposure of a large
surface area of skin for 20 to 30 minutes can produce approximately
10,000 IU of vitamin D in White people (22). A dose that causes redness
of 6% of the skin is equivalent to the ingestion of 600-1000 IU of
vitamin D (23). (The Scientific Advisory Committee on Nutrition and
National Institutes of Health recommend 200 IU daily.) Exposure during
the spring, summer, and fall of the hands, face and arms two to three
times a week is sufficient in White people (23). Asian-Indians may
require 3 times, and Blacks may require 10 times as much exposure as
Whites under the same sunlight conditions (24). Changes in the amount of
vitamin D in the body are primarily regulated by sun exposure, and not
by the diet (25,26).
The amount of vitamin D you have in your
body during the winter months is based on the vitamin D you produce
during the spring, summer, and fall. The vitamin D made in the sunshine
months of the years is stored in your body fat and slowly released
during the darker months. Plasma concentrations of 25-hydroxy vitamin D
(25-OHD) in winter of 15.0-22.5 nmol/l require that the concentration in
the previous summer was over 40 nmol/l (27).
Ultraviolet radiation is natural and
provides benefits far beyond the production of the hormone called
vitamin D (24). Apart from vitamin D synthesis there are a number of
known ways that sunlight can affect a person's health. Some of the
discovered mechanisms involve the direct alterations of the immune
system, locally and systemically; modulation of other hormones like
melatonin, calcitonin, and melanocyte stimulating hormone; and changing
the number and function of cells present in the skin (28,29) Sunlight
also establishes circadian rhythms. Undoubtedly, many important
mechanisms for the benefit of natural sunlight remain to be discovered.
Exposure to sunlight for extended periods
of time does not cause vitamin D toxicity. However, overexposure from
the sun or a tanning bed can cause skin damage.
Tanning (Sun)
Beds Are the Second Best Way to Raise Vitamin D
Indoor tanning machines emit the same
spectrum UVB radiation, as does sunlight. In areas of the world where
sunlight is limited, when people's lives do not lend themselves to
outdoor activity, and in situations where patients cannot absorb vitamin
D from their diet or pills (for example, people with bowel disease),
artificial ultraviolet light has been used to correct vitamin D
deficiency. People using an indoor tanning bed at least once a week can
raise their vitamin D levels 150% higher at the end of winter compared
to nonusers (30). Many other studies support the effectiveness of
tanning beds for the production of vitamin D (31).
Tanning beds have a bad reputation mainly
because they are used improperly. Overexposure and resulting skin damage
is easy to do because tanning beds can give out greater doses of
ultraviolet rays than the midday Mediterranean sun. A recent survey
found that the typical user of tanning beds is female, between 17 and 30
years old, and tends to live a comparatively unhealthy lifestyle;
smoking cigarettes and drinking alcohol more frequently, and eating less
healthy food than nonusers. They also lack knowledge about the health
risks of ultraviolet radiation (32). Improper use is the reason tanning
bed users have higher risks of skin cancers, skin damage, and premature
aging (33). The same adverse effects are the destiny of those who
overdose on natural sunshine.
Pills Are the
Last Choice to Raise Vitamin D Levels
Some people are unable or unwilling to
get outdoors or unable to afford to use a tanning bed. The elderly and
infirm confined to nursing homes, long-term care facilities, and their
own homes are at an especially high risk of developing deficiencies.
Adequate oral daily supplementation is as little as 200 IU of vitamin D
for healthy adults not exposed to sunshine. Darker skinned and elderly
people require more. Common recommendations are for 2000 to 4000 IU
daily of over-the-counter vitamin D to correct vitamin D blood levels.
Signs of vitamin D toxicity appear only after daily doses exceeding
10,000 IU. (1 mcg vitamin D [cholecalciferol] = 40 IU). Vitamin D2 is as
effective as vitamin D3 in maintaining circulating concentrations of
25-hydroxyvitamin D (34). Remember the topic of this newsletter: The
benefits from taking pills are very limited and there are adverse side
effects. The lesson is: Natural is best when it comes to food and
sunshine.
References:
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