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

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  • Nutrition-wise blog

  • Aug. 12, 2010

    Dietary supplements not without risks

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

20 comments posted

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Do you take dietary supplements? Thinking about it? Considering one that says "all natural" because you want to avoid prescription drugs or anything synthetic?

Before you try any dietary supplements, take a close look at the bottle and the science behind the claims. Then proceed with caution. Here's why:

  • Just because you can purchase a supplement, that doesn't mean it's safe. Dietary supplements don't undergo the same scrutiny that's required of prescription medications.
  • Dietary supplements, including herbal supplements, aren't benign. Whether they're in the form of pills, drinks, powders or foods, supplements can have strong effects in the body. Supplements can also interact with prescription medicines, leading to potentially dangerous reactions.
  • "All natural" on the bottle is no guarantee that a supplement is in fact all natural. In recent years, the Food and Drug Administration has discovered chemicals, prescription drugs and steroids in some supplements.
  • Few supplements have rigorous science to support their claims. In all fairness, it's possible the science just isn't there yet. Whatever the reason, you're in uncharted waters when it comes to most supplements.

If you're currently taking or considering taking dietary supplements, keep a few key points in mind:

  • Be skeptical. If a claim seems too good to be true, it probably is. When in doubt, ask your doctor or pharmacist.
  • Talk to your doctor. Tell your doctor if you're taking a supplement and if you experience any problems with it.
  • Look at the big picture. Some groups may be more at risk for adverse effects with supplements. These include teenagers, women who are pregnant or breastfeeding, people who take multiple medications and those planning to undergo surgery.
  • Look at your lifestyle. Why are you considering taking a supplement? Could you achieve the same results by getting more sleep, starting to exercise or eating a healthy diet?

What have been your experiences with supplements? Positive? Negative? If you had an adverse reaction, was it mild or severe?

- Katherine

20 comments posted

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  • March 28, 2013 5:10 p.m.

    I was anemic and did not want to take a vitamin. However the health food store owner told me about Floradix iron. It is made out of only concentrated fruit juices. I took it for two months and my doctors said that my iron level improved dramatically. If you are going to go natural, I would certainly recommend Floradix.

    - April

  • September 25, 2012 10:56 a.m.

    My mom diagnosed me with POTS after reiandg about it on the internet, too! I'd had three seizures over the course of six months, and anti-convulsants didn't work. Tests confirmed I didn't have abnormal brain activity, so doctors couldn't figure out what was going on. I often felt dizzy and have had persistent stomach problems since childhood, and it took lots of web surfing to finally figure out what was wrong. We urged doctors to perform a tilt-table test, and sure enough it was POTS. You can read my full store on my blog click my name to go to it. This is such an amazing story, and it's great that Hayley is doing better!

    - Sonu

  • August 25, 2012 9:35 a.m.

    I'm 74 yrs. old with Diabetes 2. Every doctor I have gone to seems to know very little about nutrition and vitamins. My experience has been for doctors to push drugs to put a bandaid on illnessis. Maybe some cases need drugs...... I'm sure. However, drugs are a fast and easy way to put a bandaid on the problem. Doctor's had me on 9 different drugs per day and I was a walking zombie! With an AC1 reading of 6.5. Since I've been on the necessary supplements, from Dr. Weil (who is a Nutritionalist and Homeopathic phyiscian) his Anti-Inflammatory Food Pyramid put me on a healther road with lower cholestrol, lower HBP, and a Diabetic AC1 reading of (one!) Yes, I said #1. I agree supplements should be considered. Although be careful of the sauce from where one buy's supplements. As far as drugs are concerned they have caused more harm to people than any vitamin I ever heard of.

    - Diane

  • July 4, 2012 9:28 a.m.

    I just recently started taking a dietary supplement called Reyouth Slim, Its Chinese manufactured. It claims to contain natural herbs, with no side effects. Designed to relieve high blood pressure and promote fat elimination amongst other things. It is recommended that u take along with a diet of vegetables and high protein, it claims you will lose 10-15lbs in a month. A friend of mine.tried it without changing her diet and with out exercise and lost 10lbs. im on day 5 and haven't experienced any side effects.

    - fern

  • June 19, 2012 11:22 a.m.

    Wow! I have been using suppliments for six months now. My experiences have been life changing! I had arthritis in both hands so bad that I had to use both hands to brush my teeth. Now, I am no longer in chronic pain! In addition I researched what suppliments could help my scalp psoriasis. I am very pleased to say that my horrific years long experience with horrific ailment is behind me! I now use regular shampoo and conditions! I, for one am delighted that I tried suppliments!

    - Barbara

  • April 23, 2012 12:41 p.m.

    What dietary supplements would you recommend for someone who is dieting extremely right now? I want to do the hcg diet. Are there pills that can help with the hunger?

    - Jenny

  • February 24, 2011 2:49 p.m.

    Herbalife? Has anyone heard of them? Side effects? Good bad product

    - Joan

  • January 17, 2011 1:01 p.m.

    These general admonitions are fine for the uninitiated. How about some specific refs concerning lipoic acid, acetyl carnitine, taurine, chromium and selenium ? What are the pros and cons ? These have some specific claims associated with benefits and insightful info is difficult to find. In appropriate amounts they seem safe so this is not about megadoses but mechanism of benefit or possible harm is what would be valuable. Generalities about supplements are useless to a user who tries to keep up on the subject.

    - Robert

  • December 10, 2010 10:46 p.m.

    A recent TV news report highlighted a study (unsure of source) that has found Calcuim supplements that contain only calcium have the effect of precipitating calcium in the blood vessels. The report stated no study has been done to assess the efficacy of calcium/co-nutrient supplements. Is this really so? How does one go about finding out? The supplement I take contains Calcium Citrate & Hydroxyapatite, Magnesium, Manganese, Zinc, Vitamin K1, Vitamin D3 and Boron and herbal extract Equisetum. I am over 60 yrs of age and have been advised to supplement.

    - Heather

  • September 29, 2010 4:14 p.m.

    Stevia has also been dubbed a dietary supplement by the FDA although it is actually an all together sugar substitute and actually healthy for you. Many people aren't even aware of it. I don't think this blog allows links but you should definitely check it out if you're interested in a sweetener that is 100% natural, has zero calories, zero carbs and completely safe for diabetics. It actually comes from the Stevia plant and has many vitamins and nutrients that are super important for you daily intake. I love giving it to my family because I know it's good for them.

    - Mars

  • September 23, 2010 1:13 a.m.

    they say the best cure is prevention. it is..its better to take care of our health earlier than to experience diseases in the later part especially in the man's health

    - men's health

  • August 19, 2010 10:43 a.m.

    I am VERY reluctant to discuss vitamins with my doctor. For the first time in 12 years she asked me if I take a multivitamin and added it to the computer history on the new electronic records form. She wants me to bring the label so she can add the info. However, for the last 12 years, this "top doc" has dismissed the concept of supplements as totally unnecessary because "everyone gets what they need from food." If this were true - there would be little need for the medical profession at all! The medical profession seems un-read on the subject of changing mineral content of soils for food production, and unclear that most of America is no longer eating "3 square meals a day" prepared from fresh ingredients. My Mom read and studied nutrition and supplements, bought low-sodium foods, rinsed canned goods 7x with bottled water, and mixed whole grains with legumes to achieve complete proteins. Self-taught, she taught us to look to our health by avoiding medications as quick solutions. I think most MDs prescribe too quickly and do so based on what the most recent drug salesman read to them from the brochure. I am shocked at their ignorance of science digests of current research in a university-rich environment. No, I don't think I'll ask my doctor. Let her take the lab tests and assess the consequences of my nutritional conscientiousness.

    - Janie

  • August 19, 2010 7:55 a.m.

    I subscribe to consumerlab.com. They test supplements (in the same way that Consumer Reports tests other products) and report on which supplements were found not acceptable, such as contain lead, don't have the amount of certain items claimed on the bottle, etc. They also list what each supplement can or can't do, backed by scientific studies, and possible reasons for not taking a certain supplement. I am 76 and have taken supplements for many years. Have never had to take prescription drugs for my chronic health problems, including osteoarthritis and borderline high blood pressure. I take astragalus for immunity and almost never catch colds as I used to quite often. Neither have I had flu.

    - Marilyn

  • August 18, 2010 9:33 p.m.

    I have used several supplements over the years, but I continue them only if I see an improvement. I had show dogs with dry skin and drier coat. I used fish oils on them first and saw an amazing difference in skin and coat in three months. I saw the same difference in myself. I have carpal tunnel and B6 actually helps some, it also helps my Raynauds symtoms. I take selenium it has helped faid my age spots. My oncologists had me talke calcium and fish oils and when I get leg cramps magnesium will stop them. So while the vitamins may not be pure or exact I can see some actual benefit from some of them. I will give them a try for 6 months and if I can't see a benefit from them or if my Doctor advises against them I quit taking them. I am amazed at how many my oncologist suggest I take. She seems more aware of their adverse affects and benefits then my family doctor.

    - lee

  • August 18, 2010 10:46 a.m.

    I've taken vitamin and mineral supplements in the past but never noticed any difference in health. There is a ton of recent reseasrch showing thaking supplements is a bad idea unless a deficiency is detected that cannot be met with food. Folic acid has been shown to increase risk for breast cancer. Omega 3s in form of fish oil suppress the immune system (they can begotten from dark green leafy veges), St. Johns wart has numerous side effects from skin reactions to the sun to increased Rest Leg Syndrome, and the Britich journal of medicine just published a study showing women who take calcium supplements have a r0% higher rish for heart disease and stroke. Even too much animal protein, which almost all Americans take in, causes kidney stones, excretion of calcium from bones, and numerous other problems. I'd rather spend my money on good gorganic veges and fruit and squash, potatoes and beans than waste it on supplements that camke unproven claims and often damage one's health.

    - Tom

  • August 16, 2010 5:58 p.m.

    Good points. I've read the book In Fitness and In Health. I try to follow this for a healthy lifestyle. Because I know I don't get all the nutrients I need from my diet, I take a daily vitamin supplement.

    - Mary

  • August 16, 2010 9:45 a.m.

    Fair points. We dietitians should pay more attention to how dietary supplements interact with common medicines. Doctors are not very familiar with these issues, and the field is evolving rapidly. For example, warfarin (and consequely INR-values) is affected by multiple herbs.

    - Reijo

  • August 14, 2010 8:32 p.m.

    Agree 100% with Jon. I'd like to see more specifics and less blanket statements or generalizations.

    - Joe

  • August 13, 2010 1:40 p.m.

    The same concepts can (and maybe should) be applied to everything. Just because you can purchase a food does not mean it is safe (e. coli, salmonella, trans fats, high sodium, etc). Just because you can purchase a drug does not mean it is safe (500,000 reported adverse events per year for FDA approved drugs, Vioxx and other drug recalls, 100,000 annual deaths whiel using drugs correctly). Just because you can purchase a car does not mean it is safe (Toyota, etc). The issue of adulterated/contaminated supplements must be addressed. Most of this seems to be within the sports performance, sexual performance, and energy/diet categories, and FDA is taking enforcement action including seizures, recalls and criminal charges. More such enforcement activity is necessary to put an end to these illegal and dangerous practices. In fact, the body of science is much larger than most know or state. Rather than characterize the entire supplement category with such generalizations, it would be more helpful to point out which supplements do have robust science regarding safety and effects. Things like folic acid, vitamin D, calcium, omega 3s, pycnogenol, garlic, certain mushrooms, st. john's wort, etc. Consumers should be skeptical and careful, but should not eliminate the use of well studied and helpful supplements and herbs.

    - Jon

  • August 13, 2010 1:34 p.m.

    Great advise!

    - elissa

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