flyinghigh.org » Vitamin E

Vitamin E + N-acetyl cysteine supplementation reduces throat cancer risk

Simon Nettle — Wed, 10 Dec 2008 02:10:24 +0000

This study, which builds on previous research that esophageal cancer is caused in part by oxidative stress following gastroesophageal reflux (heartburn), shows that supplementation with vitamin E and N-acetyl cysteine goes some way to protect against this.

Effect of alpha-tocopherol, N-acetylcysteine and omeprazole on esophageal adenocarcinoma formation in a rat surgical model.

Int J Cancer. 2008 Oct 20; PMID: 19058177

Hao J, Zhang B, Liu B, Lee M, Hao X, Reuhl KR, Chen X, Yang CS.

Department of Chemical Biology, Susan Lehman Cullman Laboratory for Cancer Research, Ernest Mario School of Pharmacy, Rutgers, The State University of New Jersey, 164 Frelinghuysen Road, Piscataway, NJ.

We previously demonstrated that oxidative stress subsequent to gastroesophageal reflux is an important driving force of esophageal adenocarcinoma (EAC) formation in the esophagogastroduodenal anastomosis (EGDA) rat model. This study investigated the possible tumor inhibitory effects of 2 antioxidants, alpha-tocopherol (389 and 778 ppm), N-acetylcysteine (NAC, 500 and 1,000 ppm), and their combination (389 and 500 ppm, respectively), as well as an antacid therapeutic agent, omeprazole (1,400 ppm). The rats were fed experimental diets 2 weeks after EGDA. All the animals were sacrificed 40 weeks after EGDA and the esophagi were harvested for histopathological examination. alpha-Tocopherol dose-dependently decreased the incidence of EAC (p = 0.03), with 778 ppm alpha-tocopherol reducing the incidence of EAC to 59% (16/27) in comparison with 84% (26/31) in the control group (p = 0.04). Supplementation of alpha-tocopherol also increased the serum concentration of alpha-tocopherol. NAC at 500 and 1,000 ppm did not significantly decrease EAC incidence; however, the combination of alpha-tocopherol 389 ppm and NAC 500 ppm significantly reduced the incidence of EAC to 55% (15/27) (p = 0.02). alpha-Tocopherol alone or in combination with NAC significantly reduced the number of infiltrating cells positively stained for 4-hydroxynonenal. Omeprazole showed only a slight nonsignificant inhibitory effect at the dose given. Our results suggest that supplementation with alpha-tocopherol inhibits the development of EAC in the rat EGDA model and similar inhibitory effect can be achieved when a lower dose of alpha-tocopherol is used in combination with NAC. (c) 2008 Wiley-Liss, Inc.

Now, Vitamins C & E (in low doses) don’t prevent cancer, either

Simon Nettle — Mon, 17 Nov 2008 07:16:07 +0000

The Physicians’ Health Study II was a large-scale, long term, randomized clinical trail that included 14,641 physicians taking either 500mg vitamin C or 400IU vitamin E or their respective placebos. It was found that after a follow-up of 10 years, no effect was found on the incidence of total cancer.

It was noted that while there were no effects on the incidence of cancer, supplementation did not cause harm.

So, we have a study telling us that vitamins C & E confer no benefit regarding cardiovascular health, and now no benefit on cancer. Is it time to chuck them out? Are they a waste of money?

Well, they still increase the life spans of fruit flies, so there’s got to be some good. Another point is that they only used 500mg/day of vitamin C, not really all that much, especially considering that far greater amounts are produced in the bodies of those animals that don’t lack the genes to produce vitamin C endogenously. I currently take 2000mg/day.

I’m going to review the literature when I get the time and bring me (and you) up to date with all the current thought on the matter, but I’m pretty busy at the moment, so you might have to wait a while.

Thanks to Eurekalert! for the info.

Vitamins E and C not helpful in preventing heart attacks

Simon Nettle — Tue, 11 Nov 2008 06:21:07 +0000

According to a report brought to my attention by Sciencedaily.com, a study on the risk of major cardiovascular events while taking vitamin C and E showed no effect in reducing their incidence.

While the historical studies seemed to suggest that vitamin E and C supplementation might reduce cardiovascular disease on account of their anti-oxidant properties; in this prospective study of 14,641 physicians, there was no significant difference in total mortality between the supplemented group and the placebo group.

Also, vitamin E supplementation was associated with a slightly increased risk of hemorrhagic stroke. This might be linked to the finding that excess vitamin E can go beyond reducing the likelihood of unwanted clots, instead causing bleeding.

In conclusion, the authors write:

In this large, long-term trial of male physicians, neither vitamin E nor vitamin C supplementation reduced the risk of major cardiovascular events. These data provide no support for the use of these supplements for the prevention of cardiovascular disease in middle-aged and older men.

What does this mean for avid vitamin supplementers such as me? Well, nothing yet. Vitamins E and C are still antioxidants and still hold promise for a range of other beneficial effects related to these properties. Just because reducing the risk of cardiovascular events is no longer considered to be part of their repertoires (at least at these dosages), a wide range of benefits is still attributed to vitamin C and vitamin E.

To be honest, in devising my own supplementation regimen, I automatically added these antioxidant vitamins without carrying out much research, simply because their popularity gives them such credence. I’m thinking now that it might be worthwhile taking a closer look at what has been coming out of research departments recently regarding their efficacy.

Reference: Vitamins E and C in the Prevention of Cardiovascular Disease in Men. JAMA, 2008;300(18)