Taking a daily vitamin pill (vitamin A) could prevent skin cancer, scientists reveal

Scientists say taking food supplements containing vitamin A can make people less likely to develop melanoma, the deadliest form of the disease. A study found that retinol - a key component of Vitamin A - could protect against the illness.

The strongest protective effects were found in women and in sun exposed sites, suggesting retinol actually combats skin cancer. However, there was no association between dietary intake of vitamin A, found in liver, eggs and milk, and a reduction in risk.

Their findings, published in the Journal of Investigative Dermatology, found those who used retinol regularly were 60 per cent less likely to develop skin cancer, rising to 74 per cent among participants on the highest doses of more than 1,200 mg a day.

Vitamin A

FACTS:

Vitamin A is fat-soluble. It requires fats as well as minerals to be properly
absorbed by your digestive tract.
It can be stored in your body and need not be replenished every day.
It occurs in two forms—preformed vitamin A, called retinol (found only
in foods of animal origin), and provitamin A, known as carotene (provided by
foods of both plant and animal origin).
Vitamin A is measured in USP Units (United States Pharmacopeia), IU
(International Units), and RE (Retinol Equivalents). (See section 168.)
1,000 RE (or 5,000 IU) is the recommended daily dosage for adult males to
prevent deficiency. For females it’s 800 RE (4,000 IU). During pregnancy the
new RDIs/RDAs do not recommend an increase, but for nursing mothers an
additional 500 RE is suggested for the first six months and an additional 400
RE for the second six months.
There is no formal RDI/RDA for beta-carotene, because it is not (yet) officially
recognized as an essential nutrient. But anywhere from 10,000–15,000
IUs of beta-carotene are needed to meet the RDI/RDA for vitamin A.

NOTE: Throughout this book, beta-carotene will be the preferred form of vitamin
A. I find it preferable because it does not have the same toxicity potential
of vitamin A. Moreover, it has been shown to be a preventive for certain types
of cancer, helpful in lowering levels of harmful cholesterol, effective in boosting
the immune system by increasing the number of infection-fighting T lymphocytes
(T cells), and a significant factor in reducing the risk of heart disease.

BEST NATURAL SOURCE:

Fish liver oil, liver, carrots, dark green and yellow vegetables, eggs, milk and
dairy products, margarine, and yellow fruits. (Note: The color intensity of a fruit
or vegetable is not necessarily a reliable indicator of its beta-carotene content.)

SUPPLEMENTS:

Usually available in two forms, one derived from natural fish liver oil
and the other water dispersible. Water-dispersible supplements are
either acetate or palmitate and recommended for anyone intolerant to
oil, particularly acne sufferers. 5,000 to 10,000 IU are the most common
daily doses.

Vitamin A acid (retin A), which has often been used in the treatment of
acne, and is now being marketed as a treatment for eradicating superficial
wrinkles, is available only by prescription in the United States.

TOXICITY AND WARNING SIGNS OF EXCESS:

More than 50,000 IU daily, if taken for many months, can produce toxic
effects in adults.
More than 18,500 IU daily can produce toxic effects in infants.
More than 34,000 IU beta-carotene daily can cause yellowing of the skin.
Symptoms of vitamin A excess include hair loss, nausea, vomiting, diarrhea,
scaly skin, blurred vision, rashes, bone pain, irregular menses, fatigue,
headaches, and liver enlargement.

ENEMIES:

Polyunsaturated fatty acids with carotene work against vitamin A unless
there are antioxidants present. (See sections 100–117 for antioxidants, and
section 293 for drugs that deplete vitamins.)

source:
http://www.amazon.com/Earl-Mindells-Vitamin-Bible-Century/dp/0446607029/ref=sr_1_2?ie=UTF8&qid=1330823516&sr=8-2

"NOTE: Throughout this book, beta-carotene will be the preferred form of vitamin A. I find it preferable because it does not have the same toxicity potential of vitamin A. Moreover, it has been shown to be a preventive for certain types of cancer, helpful in lowering levels of harmful cholesterol, effective in boosting the immune system by increasing the number of infection-fighting T lymphocytes (T cells), and a significant factor in reducing the risk of heart disease."

There is a major study that indicates that beta-carotene CAUSES an INCREASE in the incidence of lung cancer in smokers. (I don't know how or if that applies to ex-smokers.) The increase was so significant that the study was terminated early.

>>Vitamin A: 1 IU is the biological equivalent of 0.3 microgm retinol, or of 0.6 microg beta-carotene

So to get 1200 mg, one would have to take a huge number of 10,000 IU vitamin A pills — I got 400,000 Vitamin A capsules of 10,000 IU each, to get 1200 mg of Vitamin A.<<

First, I suspect the article misstated the 1200 mg. It probably was 1200 micrograms. Assuming that’s the case, and taking your 1 IU=.3microgm as true, that would mean a daily dose of over 4,000 IU, which would at least be a sensible number.

Second, even if it is milligrams, as the article states, your math is off I think. It would be 1,000 times the 4,000 IU I got assuming micrograms, or about 400 capsules per day each containing 10,000 IU, not 400,000.

That said, it will be interesting to find out what Dr. John Cannell of the Vitamin D Council says of this study, since he’s on record stating that high doses of vitamin A are harmful because they frustrate the effects of Vitamin D3, and a vitamin D3 deficiency is being implicated in dozens of diseases.

Finally, the last three paragraphs of the article were:

“However, Dr Claire Knight, senior health information officer at Cancer Research UK, said: ‘We don’t recommend people start taking retinol supplements based on this study, particularly as high doses can be toxic.

‘The result was based on a very small number of people with melanoma, and the authors didn’t account for other important factors that influence the risk of skin cancer, such as the number of moles a person has.

“And crucially, when the authors looked at whether a particular dose was linked to risk, the link between retinol and melanoma disappeared.’

I’d be very wary of taking vitamin A in retinol form on the basis of this study, given the last paragraph above, especially given Dr. Cannell’s warning on it frustrating the positive effects of vitamin D3.

If you smoke, it’s probably not very wise to use Vitamin A:

“found 28% more lung cancers and 17% more deaths in smokers and asbestos workers who took beta carotene and vitamin A supplements.”

http://news.bbc.co.uk/2/hi/health/330827.stm

“Clinical trials have found that vitamin A supplements do not lower the risk for lung cancer in smokers and actually increased their risk for dying of lung cancer and heart disease”
“A 2007 review of 68 studies of vitamin supplements concluded that people taking beta carotene or vitamin A supplements had a shorter life expectancy than those who did not take these supplements.

Synthetic retinoids that are more potent than natural vitamin A or beta carotene have shown some ability to reverse pre-cancers in the cervix, mouth, throat, and skin. They also may help prevent new tumors in people who have already been treated for these forms of cancer. But more clinical research is needed. Several clinical trials involving retinoids have been completed and others are still going on.”

http://www.cancer.org/Treatment/TreatmentsandSideEffects/ComplementaryandAlternativeMedicine/HerbsVitaminsandMinerals/vitamin-a-and-beta-carotene

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