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    Jennifer Nelson, M.S., R.D. and Katherine Zeratsky, R.D.

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  • Jan. 23, 2009

    Antioxidant supplements: Prevention in a pill?

    By Jennifer Nelson, M.S., R.D. and Katherine Zeratsky, R.D.

34 comments posted

I'm more convinced than ever that we need to give up the knee-jerk reflex that supplements are a nutritionally effective way to prevent disease. Why such a strong statement? The two lead articles in the recent issue of the medical journal "JAMA" show that the antioxidant vitamins C, E and the mineral selenium have no effect on preventing prostate cancer or other cancers in men.

Flash back to last year — and the year before that. In April 2008 a sophisticated analysis was conducted of all the randomized trials of antioxidant supplements involving adults. Together the trials included 232,606 participants. The analysis confirmed the previous year's "JAMA" report that the antioxidant supplements beta carotene, and vitamins A and E seem to increase risk of death.

As far back as 2000, large-scale clinical trials did not support — and even questioned — the use of vitamin E and beta carotene for protection against heart disease. And in the 1990s, clinical studies looking at whether antioxidant supplements protected smokers against lung cancer found that beta carotene and vitamin A actually increased cancer risk.

All of these studies have their roots in the observation that people who eat a diet high in vegetables and fruit (main sources of antioxidants) have lower incidence of various cancers and diseases associated with damage from what is called oxidative stress. Researches tested compounds in vegetables and fruit they hoped would prevent or slow down damage to cells caused by oxidation. While this is a laudable goal, it's beginning to be clear that the benefits of an antioxidant-rich diet can't be boiled down and put into a nutritional pill.

Vegetables and fruit are filled with antioxidants in a variety of forms. For example, there are several hundred types of carotenes (beta carotene is just one of them) and 8 forms of vitamin E. This is a strong argument for vegetables and fruit over pills that contain single forms of nutrients. Furthermore, vegetables and fruit contain combinations of these compounds that dynamically interact. Finally, supplements are not regulated and do not undergo the strict testing that drugs do (but that's a topic for another blog).

So rather than chasing after a silver bullet, maybe we should focus on eating a healthier diet. The U.S. Dietary Guidelines recommend eating each day:

  • 3 to 5 servings of fruit
  • 4 to 8 servings of vegetables
  • For a total 7 to 13 servings

And yet a 2005 survey of almost 350,000 adults in the U.S. found that, on average, Americans eat 1.6 servings of fruit and 3.2 servings of vegetables a day. This is terrible!

So what are your thoughts? Did the studies described above cause you to pause and become "anti" about antioxidant supplements? How many servings of vegetables and fruit do you eat every day? I want to hear from you.

34 comments posted

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  • January 27, 2009 5:43 p.m.

    My concerns about the studies related to nutrients are almost always planned and conducted by researchers who are financially influenced financially and otherwise by pharmaceutical companies. I suggest you and your audience read some books that describe the manipulation of Big Pharma. In a private meeting with a Board member of a pharmaceutical company, I asked if they were making any progress in preventing or curing diseases. The director had a quick response. "It's a money game. We're there to increase sales and profits. If we cure disease, we're out of business, and our stockholders who we represent will suffer total loss." If you really want to cover this issue thoroughly, an excellent book is available, written by Marcia Angell, MD entitled The Truth About the Drug Companies. Dr. Angell was editor of The New England Journal of Medicine for more than 20 years and describes the fraudulent techniques many of which pharmaceutical companies exploit to favor the approval of pharmaceutical agents and discredit nutrients, many of which have powerful disease prevention and curative powers. Two other books focus on similar behavior by the pharmaceutical companies. One is Our Daily Meds by Melody Peterson and Politics in Healing by Daniel Haley. So, my opinion is that anyone not familiar with these credible reports, particularly the one by Dr. Angell is likely to be misled about any studies concluding that nutritional supplements are of no value.

    - Robert E. Lookabaugh, OD

  • January 27, 2009 4:00 p.m.

    Its really difficult for me to eat that many servings of fruits and veggies, so I replace with supplements, I'm 67 work out about 3 or 4 times per weeks and I feel great and look pretty good. thank you

    - margo moody

  • January 27, 2009 2:21 p.m.

    What is Mayo's reponse to the people complaining about the type of Vitamin E used the Clinical Trials??

    - WALDYN J BENBENEK

  • January 26, 2009 6:53 p.m.

    What this article does not focus on enough is that supplements from a bottle do not provide the phytonutrients that have health benefits including the ability to boost the antioxidant system called Nrf2....

    - heirsonline

  • January 24, 2009 6:24 a.m.

    I w2as pre-diabetic with a terrible family history of Diabetes and I got Gout as a result of my effort to lower my cholesterol. My fasting blood glucose level is now normal and I did not have a gout attack in over two years. How did I do it? Fruits, vegetables, cheese and a spoon full of dry parsley (it contains the most of an anti oxidant to prevent gout. By the way it is also two years that I did not consume allopurinol! My last attack was a month and half with a walker. Today I exercise 5 days a week with weights, seat ups, push ups and climb the stairs 20 time a day. I am 74. My doctor shakes his head in disbelief. I have 3 stents caused by my previous terrible diet.

    - Albert Reingewirtz

  • January 23, 2009 3:12 p.m.

    I find it very disturbing that the statements in reference to Vitamin E are so poorly supported by not understanding the significance of the type of Vitamin E used in the studies. If you wish to have a better understanding of how to interpret these types of studies you are welcome to contact me. Please stop supporting something that you do not understand. Thanks.

    - Jim Capps

  • January 23, 2009 10:33 a.m.

    I take OPC-3, a powerful anti-oxidant, in Isotonix form and I have noticed tangible results. Rosacea has cleared up. I have a higher level of energy. I have fewer aches and pains. My allergies have improved.( stopped taking astelin. Saved $125/Qtr)I don't know, but I would like to think that my immune system is stronger as a result of taking OPC-3. I do try to eat veggies and fruit on a regular basis, but not always possible so I supplement with OPC-3.

    - Ron Amundson

  • January 23, 2009 7:51 a.m.

    Supplements are what their name says they are...supplements. I have always said that the key to a healthy dietary lifestyle is 75% diet and 25% supplemental. I would love for all of my clients to have five or more servings of vegetables daily. However, they do not and it takes a long time to change these habits. Supplements are not the savior for every malady. However, to this point, supplement studies such as the ones you alluded to are structured in the "drug model" and are not appropriate to gauge the true preventative value of dietary supplements. In addition, nutrient dosage depends upon individual need which must be scrutinized by a knowledgeable health professional. Lastly, these recent studies were set up to fail from the beginning. For example, in the case of vitamin E, any health professional that incorporates dietary supplements into their lifestyle recommendations knows that the synthetic form of vitamin E is worthless. In addition, mixed tocopherols (alpha, beta, gamma, delta, and tocotrienols), not alpha tocopherol alone, have shown to be much more effective in research. The studies you cite used synthetic alpha tocopherol only.

    - Bonnie Minsky MA, MPH, CNS, LDN

  • January 23, 2009 12:30 a.m.

    I will still continue to take alpha lipoic acid and silymarin until someone convices me otherwise.

    - JD

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