I used to drink a lot of carrot juice now...

[clyde_on]

I am afraid of it see why:

http://www.cancer.gov/cancertopics/factsheet/Prevention/betacarotene

[Fish]

That study focused on smokers, former smokers and persons exposed to asbestos. Groups already at significanlty increased risk for lung cancer. They also stated in their findings:

"The results of the Physicians' Health Study showed no benefit or harm to nonsmokers who took beta carotene every other day for 12 years. The results from CARET and the ATBC Study do not provide information about the effects of beta carotene supplements on non-smokers."

So if you're a non-smoker, go enjoy your carrot juice, the benefits likely outweigh the risks - although even a good thing can be overdone.

FYI in one paper I read, 330ml of carrot juice contained 27mg beta-carotene (J. Nutr. 134:1081-1083, May 2004), the study you cited use 20mg purified beta-carotene.

[Michael112]

My multivitamin contains 2500IU of vitamin A, dont know if that would increase risk of cancer or not but it is essential to human health so I am going to continue taking it.
Beta-Carotene also showed to increase the rate of prostate cancer.

Vitamin D and E have shown to decrease growth of cancer, so with cancer and vitamins it works both ways.

[djmac]

Michael,

Whatever you do, do not overdo the Vit A...It is, after all, also a deadly poison.

djm

[Michael112]

I never overdo vitamins, I have learnt my lesson from accidently taking 100mg of B6, I started panicing and flushing and looked at the label and realised they including 50mg in there zinc pill and another 50mg in there magnesium pill, I felt so panicy I dumped 120 pills worth of activated charcoal lol.

But yea vitamin A and D are toxic in high doses, they have a health warning about vit A on all suppliments containing it, I never take more then 2500IU from my supps wich is the standard dosage, I think upper limit is 8000IU.