What's The Harm?

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Postby JeffN » Mon Sep 15, 2008 6:35 pm

And another one from the Cochrane Database, the best analysis of the medical data...

Ann Intern Med 16 Sep 2008; Vol. 149, No. 6
Therapeutics
Review: Antioxidant supplements do not reduce all-cause mortality in primary and secondary prevention.

++++++++++++++++++++++++++++++++++++++

Bjelakovic G, Nikolova D, Gluud LL, Simonetti RG, Gluud C.
Antioxidant supplements for prevention of mortality in healthy participants
and patients with various diseases.

Cochrane Database Syst Rev. 2008 Apr 16;(2):CD007176. Review.
PMID: 18425980

BACKGROUND:
Animal and physiological research as well as observational
studies suggest that antioxidant supplements may improve survival.

OBJECTIVES:
To assess the effect of antioxidant supplements on mortality in primary or secondary prevention randomised clinical trials.

SEARCH STRATEGY:
We searched The Cochrane Library (Issue 3, 2005), MEDLINE (1966 to October 2005), EMBASE (1985 to October 2005), and the Science Citation Index Expanded (1945 to October 2005). We scanned bibliographies of relevant publications and wrote to pharmaceutical companies for additional trials.

SELECTION CRITERIA:
We included all primary and secondary prevention randomised clinical trials on antioxidant supplements (beta-carotene, vitamin A, vitamin C, vitamin E, and selenium) versus placebo or no intervention. Included participants were either healthy (primary prevention trials) or had any disease (secondary prevention trials).

DATA COLLECTION AND ANALYSIS:
Three authors extracted data. Trials with adequate randomisation, blinding, and follow-up were classified as having a low risk of bias. Random-effects and fixed-effect meta-analyses were performed. Random-effects meta-regression analyses were performed to assess sources of intertrial heterogeneity.

MAIN RESULTS:
Sixty-seven randomised trials with 232,550 participants were included. Forty-seven trials including 180,938 participants had low risk of bias. Twenty-one trials included 164,439 healthy participants. Forty-six trials included 68111 participants with various diseases (gastrointestinal, cardiovascular, neurological, ocular, dermatological, rheumatoid, renal, endocrinological, or unspecified). Overall, the antioxidant supplements had no significant effect on mortality in a random-effects meta-analysis (relative risk [RR] 1.02, 95% confidence interval [CI] 0.99 to 1.06), but significantly increased mortality in a fixed-effect model (RR 1.04, 95% CI 1.02 to 1.06). In meta-regression analysis, the risk of bias and type of antioxidant supplement were the only significant predictors of intertrial heterogeneity. In the trials with a low risk of bias, the antioxidant supplements significantly increased mortality (RR 1.05, 95% CI 1.02 to 1.08 ). When the different antioxidants were assessed separately, analyses including trials with a low risk of bias and excluding selenium trials found significantly increased mortality by vitamin A (RR 1.16, 95% CI 1.10 to 1.24), beta-carotene (RR 1.07, 95% CI 1.02 to 1.11), and vitamin E (RR 1.04, 95% CI 1.01 to 1.07), but no significant detrimental effect of vitamin C (RR 1.06, 95% CI 0.94 to 1.20). Low-bias risk trials on selenium found no significant effect on mortality (RR 0.91, 95% CI 0.76 to 1.09).

AUTHORS' CONCLUSIONS:
We found no evidence to support antioxidant supplements for primary or secondary prevention. Vitamin A, beta-carotene, and vitamin E may increase mortality. Future randomized trials could evaluate the potential effects of vitamin C and selenium for primary and secondary prevention. Such trials should be closely monitored for potential harmful effects. Antioxidant supplements need to be considered medicinal products and should undergo sufficient evaluation before marketing

Amen!

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Re: Colin Cambell adresses this

Postby landog » Mon Sep 15, 2008 7:03 pm

SactoBob wrote:I am not sure if it was in his book, lecture, or audio interviews, but Campbell believes that most supplements are harmful.


I think he said something like: "It's not the beta-carotene - it's the carrot."
Thanks for reviving this thread!

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Postby Quiver0f10 » Tue Sep 16, 2008 10:20 am

I wonder how much of this study was affected by lifestyle. People seem to think popping a pill is the answer to everything. Sit and watch a few hours of TV and notice all the commericals for pills. I would be interetsed to see if they took into account how many folks took these vitamins and then continued to eat SAD and not excerisze and I would love to see another study done with folks eating well, excersziing and taking the same vitamins. I am betting the outcome would be different.
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Postby boardn10 » Tue Sep 16, 2008 4:57 pm

I hear ya Jeff!!!! However, I am in an odd spot with going through Lyme/Babesia treatment. My doctor has me on high doses of Magnesium, Viitamin C, Vitamin B complex, Kyolic Garlic, Probiotics, Iodine and some added Thyroid herbs. Not my choice.
I am tempted to skip and try to get these extras from food, but it could be an uphill battle.

It is twice as tough when you are told to avoid most fruits and only have 2-3 servings of sour fruits a week like green apples, some blueberries, lemons, limes and grapefruit.
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Postby JeffN » Thu Oct 30, 2008 3:31 pm

And, another one...

Prostate Cancer Prevention Study Halted

Vitamin E, Selenium No Help in Preventing Prostate Cancer

By Daniel J. DeNoon
WebMD Health News

Reviewed By Louise Chang, MD

Oct. 28, 2008 -- The National Cancer Institute has halted its $114 million study of whether vitamin E and selenium can prevent prostate cancer.

They can't -- at least not in the formulations and dosages used in the study, called SELECT (SELenium and vitamin ECancer prevention Trial). The safety panel for the 35,000-man study called for a halt when an early look at the data showed no benefit for the treatment.

There were slightly more prostate cancers in men taking vitamin E alone, and slightly more diabetes in men taking only selenium. But neither finding was statistically significant, meaning they were likely due to chance.

"The data to date suggest, but do not prove, that vitamin E may slightly increase the chance of getting prostate cancer, and that selenium may increase the chance of getting diabetes mellitus," warns a letter sent to study participants by the Southwest Oncology Group, which ran the NCI-funded study.

Study participants were told to stop taking the two pills they'd been taking every day since the trial opened in 2001. The men received either vitamin E (400 milligrams) and selenium (200 micrograms), vitamin E and placebo, selenium and placebo, or placebos alone.

The men can now ask to be told which treatment they received. And because the study was designed to look at more than just prostate cancer (it received an additional $16.5 million from various NIH agencies), study participants will continue to receive regular checkups.

"SELECT was always designed as a study that would answer more than a single question about prostate cancer," Cleveland Clinic researcher and study co-chair Eric Klein, MD, says in a news release. "As we continue to monitor the health of these 35,000 men, this information may help us understand why two nutrients that showed strong initial evidence to be able to prevent prostate cancer did not do so."

That evidence included a 1998 Finnish study of whether vitamin E could prevent lung cancer in some 30,000 smokers. It didn't, but men taking vitamin E had 32% fewer prostate cancers.

And a 1996 study failed to show that selenium could prevent skin cancer -- but found 60% fewer new cases of prostate cancer in men who took selenium for over six years.

The SELECT findings dash hopes raised by these earlier studies, says Edward M. Messing, MD, professor and chairman of urology and deputy director of the Cancer Center at the University of Rochester, N.Y. Messing serves as a SELECT study investigator.

"I am afraid it will be the end of the story for large trials of vitamin E and selenium to prevent prostate cancer," Messing tells WebMD. "For vitamin E, that is unfortunate. Probably if given in a more effective form, it would be a protective or even therapeutic agent."

Men enrolled in the SELECT study may call the NCI's Cancer Information Service at 800-4-CANCER.

SOURCES: News release, National Cancer Institute. National Cancer Institute: "Questions and Answers: Selenium and Vitamin E Cancer Prevention Trial (SELECT)," Oct. 28, 2008. "Dear SELECT Participant" letter, Southwest Oncology Group. Edward M. Messing, MD, professor and chairman of urology and deputy director, Cancer Center, University of Rochester, N.Y.

©2008 WebMD, LLC. All Rights Reserved.
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Last edited by JeffN on Thu Oct 30, 2008 3:56 pm, edited 1 time in total.
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Postby proverbs31woman » Thu Oct 30, 2008 3:47 pm

Jeff,

Thanks for posting that new information. This is very important.
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Re: What is a "large dose"?

Postby Jaggu » Fri Oct 31, 2008 9:54 am

deleted
Last edited by Jaggu on Mon Nov 03, 2008 6:17 am, edited 1 time in total.
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Postby Suebee » Fri Oct 31, 2008 11:16 am

If you don't eat seeds/nuts, how do you get zinc in the diet? Ditto for selenium? I understand that many vegetarian diets have been found to be deficient in zinc. When you are sick and can't eat these foods, should you take a multiple vitamin/mineral supplement? I try to find those that suggest taking 2 or 3 tablets a day and then just take one. But I also take some odd ones, such as quercetin/bromelain for allergies or additional turmeric extracts/boswellia for arthritis/inflammation. A good diet will not totally offset stress either! What with this economy and my husband possibly being layed off, I'm not sleeping well. And I can tell--I hurt all over! I am keeping up my daily walking.
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Postby Jaggu » Mon Nov 03, 2008 6:17 am

JeffN wrote: In my "nut mix", i grind up mostly flax, some sunflower, sesame and pumpkin and a bit of brazil. A little bit every now and then goes a long way.

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Jeff



I suppose you take Flax to get omega 3s. Not sure what you are trying to get through your nut mix? 1 TBSP of flax will give highest amount of omega 3 when compared to 1 Tsp of nutmix. So there might be some good reason why nutrition Guru uses Nut Mix.
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Postby JeffN » Mon Nov 03, 2008 6:57 am

Jaggu wrote:
JeffN wrote: In my "nut mix", i grind up mostly flax, some sunflower, sesame and pumpkin and a bit of brazil. A little bit every now and then goes a long way.

In Health
Jeff



I suppose you take Flax to get omega 3s. Not sure what you are trying to get through your nut mix? 1 TBSP of flax will give highest amount of omega 3 when compared to 1 Tsp of nutmix. So there might be some good reason why nutrition Guru uses Nut Mix.



No, as I dont eat any "one" food to get any "one" nutrient. That is an allopathic approach to nutrition and not one I recommend.

The mix was something I was "playing with" at the time. The "mix" was mostly flax with a little bit of brazil nut and some minute portions of the other seeds. However, it is not necessary, or required, nor do I even take it on any regular basis. Most all of the amount I made up last year, still sits in my refrigerator. I was just experimenting in some dietary analysis and the comparing the "minimums" to the "AI" and the "DRI" in different diets and foods.

If you redid any of the analysis I posted here without the nut mix and just the 1-3 tsps of flax the results are virtually identical with virtually no change in the analysis in regard to the AIs and DRIs. If you left it out completely, the analysis is still adequate, especially when you consider actual needs and minimums.

Remember, the AI and the DRI and the RDA are all influenced by the typical dietary patterns of the country they are set for. Different countries and areas of the world have different numbers set for them by the WHO. As no one here is recommending the typical diet, the typical recommendations do not always apply. While I think most everyone is familiar with this info in regard to protein and calcium, I have also discussed it in regard to Vit E and Omega 3s and also zinc and selenium.

Also, while nuts/seeds are not required, they are not forbidden on the program.

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Postby JeffN » Mon Nov 03, 2008 7:06 am

Suebee wrote: I understand that many vegetarian diets have been found to be deficient in zinc. .


I have found many vegetarian diets to be deficient in many nutrients. :)

That is because 1) many vegetarian diets are not healthy and include lots of processed and refined foods and many vegetarian junk foods 2) the DRI for zinc and selenium is higher in the US than in other countries.

Suebee wrote:If you don't eat seeds/nuts, how do you get zinc in the diet? Ditto for selenium?


From the foods you eat! :)

Nuts/seeds are not the highest source of zinc or selenium per calorie.

Zinc (Per 100 calories)

Calabash, cooked, boiled, drained, with salt Zinc: 5.4 mg
Endive, raw Zinc: 4.5 mg
Bamboo shoots, cooked, boiled, Zinc: 4.5mg
Bamboo shoots, raw Zinc: 4 mg
Mushrooms, brown, Italian, or Crimini, raw Zinc: 4mg
Alfalfa seeds, sprouted, raw Zinc: 4mg
Squash, zucchini, baby, raw Zinc: 4mg
Chayote, fruit, raw Zinc: 4mg
Broccoli raab, raw [Broccoli rabe, Rapini] Zinc: 3.5mg
Spinach, cooked, boiled, drained, without salt Zinc: 3.5mg
Mushrooms, cooked, boiled, drained, with salt Zinc: 3mg
Asparagus, cooked, boiled, drained Zinc: 3mg
Beans, kidney, red, mature seeds, canned Zinc: 3mg
Beans, adzuki, mature seeds, raw Zinc: 1.5mg
Wild rice, cooked Zinc: 1.5mg
Oat bran, cooked Zinc: 1.5mg
Seeds, pumpkin and squash seed kernels, dried [pepitas] Zinc: 1.5mg
Seeds, sesame seeds, whole, dried Zinc: 1.5mg
Wheat, durum Zinc: 1mg
Rye Zinc: 1mg
Triticale Zinc: 1mg
Oats Zinc: 1mg
Quinoa, cooked Zinc: 1mg
Millet, cooked Zinc: 1mg

For Selenium (per 200 Calories)

Nuts, brazilnuts, dried, unblanched Selenium: 585mcg
Mushrooms, brown, Italian, or Crimini, raw Selenium: 193mcg
Mushrooms, straw, canned, drained solids Selenium: 95mcg
Mushrooms, shiitake, cooked, without salt Selenium: 89mcg
Mushrooms, cooked, boiled, drained, without salt Selenium: 85mcg
Mushrooms, portabella, raw [Portabello] Selenium: 85mcg
Mushrooms, white, raw Selenium: 85mcg
Asparagus, cooked, boiled, drained Selenium: 55mcg
Asparagus, cooked, boiled, drained, with salt Selenium: 55mcg
Asparagus, frozen, cooked, boiled, drained, without salt Selenium: 43mcg
Couscous, cooked Selenium: 49mcg
Spaghetti, whole-wheat, cooked Selenium: 42mcg
Spinach, frozen, chopped or leaf, unprepared Selenium: 41mcg
Oat bran, cooked Selenium: 39mcg
Mushrooms, canned, drained solids Selenium: 33mcg
Selenium: 32mcg Mushrooms, shiitake, dried Selenium: 31mcg
Seeds, sesame seed kernels, dried (decorticated) Selenium: 31mcg
Seeds, sunflower seed kernels, dry roasted, without salt Selenium: 27mcg
Broccoli, frozen, chopped, unprepared Selenium: 22mcg
Broccoli, flower clusters, raw Selenium: 21mcg
Lettuce, red leaf, raw Selenium: 19mcg
Rice, brown, long-grain, cooked Selenium: 18mcg
Beans, pinto, mature seeds, canned Selenium: 17mcg
Cabbage, red, cooked, boiled, drained, without salt Selenium: 16mcg
Broccoli, raw Selenium: 15mcg
Lima beans, large, mature seeds, canned Selenium: 11mcg
Beans, navy, mature seeds, canned Selenium: 10mcg
Grapefruit, raw, pink and red, Florida Selenium: 9mcg
Strawberries, frozen, unsweetened Selenium: 4mcg

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Postby JeffN » Thu Mar 05, 2009 2:29 pm

Am J Epidemiol. 2009 Feb 10. [Epub ahead of print]

Long-term Use of {beta}-Carotene, Retinol, Lycopene, and Lutein Supplements and Lung Cancer Risk: Results From the VITamins And Lifestyle (VITAL) Study.

Satia JA, Littman A, Slatore CG, Galanko JA, White E.

High-dose beta-carotene supplementation in high-risk persons has been linked to increased lung cancer risk in clinical trials; whether effects are similar in the general population is unclear.

The authors examined associations of supplemental beta-carotene, retinol, vitamin A, lutein, and lycopene with lung cancer risk among participants, aged 50-76 years, in the VITamins And Lifestyle (VITAL) cohort Study in Washington State. In 2000-2002, eligible persons (n = 77,126) completed a 24-page baseline questionnaire, including detailed questions about supplement use (duration, frequency, dose) during the previous 10 years from multivitamins and individual supplements/mixtures. Incident lung cancers (n = 521) through December 2005 were identified by linkage to the Surveillance, Epidemiology, and End Results cancer registry.

Longer duration of use of individual beta-carotene, retinol, and lutein supplements (but not total 10-year average dose) was associated with statistically significantly elevated risk of total lung cancer and histologic cell types; for example, hazard ratio = 2.02, 95% confidence interval: 1.28, 3.17 for individual supplemental lutein with total lung cancer and hazard ratio = 3.22, 95% confidence interval: 1.29, 8.07 for individual beta-carotene with small-cell lung cancer for >4 years versus no use.

There was little evidence for effect modification by gender or smoking status.

Long-term use of individual beta-carotene, retinol, and lutein supplements should not be recommended for lung cancer prevention, particularly among smokers.

PMID: 19208726
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Postby Magpie » Mon Mar 09, 2009 6:53 pm

Jeff, I've just started taking a Vitamin D supplement. After seeing this post I thought it might be a good idea to ask you what you thought about it.

Obviously the best way to get Vitamin D is from sunlight, but I live in Northern Europe and for a large chunk of the year there isn't much sunlight. I also have a fairly serious illness that stops me getting out, especially in the cold seasons.

Thanks!
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Postby JeffN » Tue Mar 10, 2009 5:36 pm

Magpie wrote:Jeff, I've just started taking a Vitamin D supplement. After seeing this post I thought it might be a good idea to ask you what you thought about it.

Obviously the best way to get Vitamin D is from sunlight, but I live in Northern Europe and for a large chunk of the year there isn't much sunlight. I also have a fairly serious illness that stops me getting out, especially in the cold seasons.

Thanks!


Hi Magpie

Vitamin D
http://drmcdougall.com/forums/viewtopic.php?t=5604
http://www.drmcdougall.com/forums/viewtopic.php?t=7237

Let me know if you have any other questions

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Postby JeffN » Tue Mar 10, 2009 5:38 pm

"Folic acid supplementation was associated with increased risk of prostate cancer."


http://www.cbc.ca/health/story/2009/03/ ... ancer.html


Jane C. Figueiredo, Maria V. Grau, Robert W. Haile, Robert S. Sandler, Robert W. Summers, Robert S. Bresalier, Carol A. Burke, Gail E. McKeown-Eyssen, and John A. Baron
Folic Acid and Risk of Prostate Cancer: Results From a Randomized Clinical Trial

J Natl Cancer Inst, Advance Access published on March 10, 2009

Data regarding the association between folate status and risk of prostate cancer are sparse and conflicting.

We studied prostate cancer occurrence in the Aspirin/Folate Polyp Prevention Study, a placebo-controlled randomized trial of aspirin and folic acid supplementation for the chemoprevention of colorectal adenomas conducted between July 6, 1994, and December 31, 2006. Participants were followed for up to 10.8 (median = 7.0, interquartile range = 6.0-7.8) years and asked periodically to report all illnesses and hospitalizations.

Aspirin alone had no statistically significant effect on prostate cancer incidence, but there were marked differences according to folic acid treatment.

Among the 643 men who were randomly assigned to placebo or supplementation with folic acid, the estimated probability of being diagnosed with prostate cancer over a 10-year period was 9.7% (95% confidence interval [CI] = 6.5% to 14.5%) in the [NOTE: supplemented] folic acid group and 3.3% (95% CI = 1.7% to 6.4%) in the placebo group (age-adjusted hazard ratio = 2.63, 95% CI = 1.23 to 5.65, Wald test P = .01). In contrast, baseline dietary folate intake and plasma folate in nonmultivitamin users were inversely associated with risk of prostate cancer, although these associations did not attain statistical significance in adjusted analyses.

These findings highlight the potential complex role of folate in prostate cancer and the possibly different effects of folic acid-containing supplements vs natural sources of folate.
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