Talk:Retinol

Dangers

According to an article at http://www.westonaprice.org/healthissues/supplements.html, vitamin A overdose did not kill any explorers:

The warnings against vitamin A usually include mention of Arctic explorers who died from vitamin A overdose because they consumed polar bear livers. Actually, the early explorers did not die from eating polar bear liver. They did suffer from exfoliative dermatitis and hair loss. In 1988, a team of Swedish scientists discovered that polar bear and seal livers tend to accumulate the metal cadmium. The symptoms for cadmium poisoning are exfoliative dermatitis and hair loss, but don't expect to hear about this on the evening news. Rather, expect continuing stories about the alleged dangers of vitamins A and D. The media and the medical establishment work together to vilify the very substances that can prevent suffering and disease.

Unfortunately it contains no references. The same information is used at (defunct) www.cureamerica.net/medicalfreedom.htm:

Another vitamin that Americans have been caused to become concerned about is vitamin-A. Its ridiculously low RDA is 5000 I.U.. A person eating a modest meal of carrots and liver consumes at least 100,000 I.U. of vitamin-A, and he does it without a doctor's prescription, and each spoonful is in violation of the RDA's. Spinach, sweet peas, potatoes, red peppers and dried apricots would also be disallowed from the doctor's prescription if the FDA ever is allowed to enforce the RDAs. In February 2001, UNICEF reported that a program that began in 1988 giving high-dose capsules of vitamin-A to strengthen the body's immune system has averted one million child deaths. If vitamin-A is so abundant in common food then how could the medical authorities convince the doctors to warn the public about the dangers of taking too much and that it could be poisonous ? The answer most frequently cited is that eating polar bear livers, which contain as much as 8,000,000 I.U. of vitamin-A, was fatal for the early arctic explorers. My God ! When was the last time that you ate polar bear liver ? The tragedy behind this ridiculous stance is that it is based on misinformation. To begin with, the early explorers did not die from eating the polar bear liver which was so delicious that they devoured large amounts at each meal, but rather became sick, suffering from dermatitis and defoliation. Then, ironically, in the late 1980's, a team of Swedish scientists discovered that polar bear liver adsorbs large amounts of cadmium metal found in the arctic water. The symptoms of cadmium metal poisoning are dermatitis and defoliation. Thus, the ailments of the early explorers were caused by the cadmium in the polar bear liver, and not the large amount of vitaminn-A. The tragedy is that despite the scientific evidence, "too much" vitamin-A still remains "toxic" in the doctors minds.

But again, no references.

-rfr

I see no reason to lend any of this credence. —Casey J. Morris 07:39, July 22, 2005 (UTC)

What reason do you have to lend credence to the point of view they're arguing against, other than the fact that you've been preconditioned with it? --81.181.165.163 13:18, 18 October 2005 (UTC)[reply]

By God, the section on vitamin A overdosing is so ingrained in the traditional thinking. Shouldn't it at least present the alternate point of view? It's the synthetic form of vitamin A (included inside most supplements) which gets toxic very quickly. The only damage that the natural version of vitamin A (liver, et al) can cause is short-lived, and clears up as soon as the high dosage is withdrawn. Dr. Joseph Mercola's view on the subject: "Natural Vitamin A Found in These Foods is Superior to Synthetic Form" One of the many Weston A. Price Foundation articles on the topic: "Vitamin A: The Forgotten Bodybuilding Nutrient"

Okay, I've also added a short paragraph to express this.

UNICEF's EXPERINCE WITH VITAMIN A OVERDOSE IN INDIA

In 2003-4 about thirty children died in North East India after an overdose of Vitamin A drops, raising concerns about the programme. Will try to get references soon.

Source for cadmium buildup in polar bear livers...

Don't know if this proves anything, just throwing it in there. http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=3961478&dopt=Citation

"Polar bear (Ursus maritimus) livers (67) from six Management Zones in the western and central Canadian Arctic were analysed for 22 elements. Several, Ba, Be, Co, Mo, Ti, V and Zr, were near the detection limit in all cases. Baseline data were obtained for the remaining elements, Ag, As, Ca, Cd, Cu, Fe, Hg, K, Mg, Mn, Na, P, Se, Sr and Zn. No statistically significant effect of age, sex or geographical location was found for any of the elements, except Cd, Hg and Se, for which age and geographical location effects were found. The frequency distribution of Zn levels was bimodal. The second peak in the distribution appeared to be related to elevated levels of Cu. The average level of Cu was 104 mg kg-1 (dry wt.), higher than other marine mammals. Average levels of Cd were significantly higher in the eastern zones, but were always less than 1.0 mg kg-1 (dry wt.), significantly lower than their prey species. This may be due to the preference of polar bears for eating seal skin and fat which is low in Cd. Mercury levels tended to be higher in the western zones bordering the Beaufort Sea, which may be related to a higher proportion of bearded seal in their diet."