Doctor's Note

This is the third of a four-part series on the quality of advice given by employees of natural food stores. For parts one and two, see Health Food Store Supplement Advice, and Bad Advice From Health Food Store Employees. You’ll find part four in Pharmacists Versus Health Food Store Employees: Who Gives Better Advice? Also, check out my other videos on dietary supplements in general. For those interested in taking a deeper look, a number suggest toxicity—including Ayurvedic medicines (see Amla and Triphala Tested for Metals); fish oil (see Is Cod Liver Oil Good For You?; Juice Plus+® (see Update on Juice Plus+®); Herbalife® (see Update on Herbalife®); blue-green algae (see Is Blue-Green Algae Good For You?); cod liver oil (see Is Cod Liver Oil Good For You?; spirulina (see Update on Spirulina); green tea extracts (see The Healthiest Beverage?); and noni juice (see Is Noni Juice Good For You?). Some supplements are likely to be health-promoting, though—check out all my videos on vitamin B12 and my videos on vitamin D. Also note that we should really try to get our nutrients from Produce, Not Pills to Increase Physical Attractiveness. You can also check out my videos on supplement use during pregnancy.

For further context, check out my associated blog posts: Plant-Based Workplace InterventionCountering Dietary Pollutants & PesticidesDr. Greger’s Natural Nausea Remedy Recipe; and How Should I Take Probiotics?

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  • Michael Greger M.D.

    This is the third of a four-part series on the quality of advice given by employees of natural food stores. See Health Food Store Supplement Advice and Bad Advice From Health Food Store Employees for parts 1 & 2. I have more than five dozen videos on dietary supplements in general for those interested in taking a deeper look, with a number suggesting toxicity, including Ayervedic medicines, fish oil, Juice Plus, Herbalife, blue-green algae, cod liver oil, spirulina, green tea extracts, and noni juice. There are supplements likely to be health-promoting though, including vitamin B12 and vitamin D, but we should really try to get our nutrients from Produce, Not Pills. Then there are another 25 videos on pregnancy and 1,000+ other topics.

    • Kpaddles

       Thanks Dr. Greger,

      I was one of the lucky ones. I went into a health food store and asked about the efficacy of a certain diet. The employee didn’t know, but she suggested I read The China Study. It has been five years since that fateful day. I am happily eating a plant-based diet with no supplements except vitamin B-12. Thanks for sharing your knowledge.

      • HemoDynamic, M.D.

        The key is to say, “I don’t know” when you really don’t know.  However, for many people (altruistically speaking) they want to help others so bad that will recommend something that they have heard might work without knowing the true consequences of their recommendations.
        Reminds me of a great line in Monty Python, The Holy Grail from Roger the Shrubber, “Oh, what sad times are these when passing ruffians can say Ni at will to old ladies. There is a pestilence upon this land, nothing is sacred.”

  • Vera Springate

    Sorry but it makes absolutely no sense for someone in such “serious/grave” situation such as HIV or pregnant to seek advice from a health food store employee.  But I will admit HIV or pregnant crowds may not be educated enough to go with advice of a minimum wage worker.

  • RobG

    Water extracts of Kava Kava, which is how it is traditional used, is not hepatotoxic and is still legal in Australia because of this. However ethanol extracts of Kava Kava are potentially hepatotoxic and are illegal here. Thought of would clarify that there is a clear difference between the two in terms of safety. 

  • Roy M.

    Are enzyme supplements safe?
    Is there any research indicating that the enzyme supplements might be harmful? Please let me know, thanks a lot.

    • Toxins

      Unless prescribed by a doctor, I see no reason to consume an enzyme supplement based on whatever advertised benefits may be said. These things almost always are harmful.

  • Lillis

    Take a look at scientific studies:

    “Hepatotoxicity and subchronic toxicity tests of Morinda citrifolia (noni) fruit.

    Morinda citrifolia (noni) fruit juice has been approved as a safe food in many nations. A few cases of hepatitis in people who had been drinking noni juice have been reported, even though no causal link could be established between the liver injury and ingestion of the juice. To more fully evaluate the hepatotoxic potential of noni fruit juice, in vitro hepatotoxicity tests were conducted in human liver cells, HepG2 cell line. A subchronic oral toxicity test of noni fruit was also performed in Sprague-Dawley (SD) rats to provide benchmark data for understanding the safety of noni juice, without the potential confounding variables associated with many commercial noni juice products. Freeze-dried filtered noni fruit puree did not decrease HepG2 cell viability or induce neutral lipid accumulation and phospholipidosis. There were no histopathological changes or evidence of dose-responses in hematological and clinical chemistry measurements, including liver function tests. The no-observed-adverse-effect level (NOAEL) for freeze-dried noni fruit puree is greater than 6.86 g/kg body weight, equivalent to approximately 90 ml of noni fruit juice/kg. These findings corroborate previous conclusions that consumption of noni fruit juice is unlikely to induce adverse liver effects..”

  • albert

    It might be an idea worth of consideration to compile a list of all of the toxic substances, dosages and counterindications – sort of a black list to check out now and then. For now one has to be really into watching all of the videos available which is not always the case for every site visitor. Somebody might see one video on benefits of cinnamon and decide to go for a couple tsp a day which is exactly what happened to me a while ago :) any drugs need clear warning even if it’s a healthy food :) and sorry if I’m such a loser and missed this list somewhere :))

  • I did a search on the site for HIV and didn’t find anything. My problem is my doctors seem to think that I need, as an HIV patient, to eat meat and dairy to maintain my health. I became vegan and lost 30 pounds. I am now 6′ and 160 pounds. My doctors freaked out because, as they say, I was getting too thin. I disagree with that. Is there anything, in studies, to suggest they are right? Thanks!

  • Thomas H. Imhoof

    As a supplement consultant in a health food store, there’s a lot I can say in response to this. #1 is don’t put all health food store employees in the same category. Some are more knowledgeable than others. Some of us have received formal training in nutrition as well as having spent countless hours studying and researching health issues on our own. Working in a health food store and getting feedback from customers on what works and what doesn’t for various health conditions has also given me insights you will never hear at a doctor’s office. #2 is that by law health food store employees cannot dispense “medical advice” of any kind. This extends into such absurdities as not being able to recommend drinking water for someone who says they are dehydrated– if a health food store employees says “You can cure your dehydration by drinking some water” it is a violation of the law even though it is simply common sense. But if I say, “I’m not a doctor, but personally I would maybe think about drinking some water” then I am in compliance with the law. It’s all in the way things are said, and health food store employees may not be properly trained in how to use the proper wording in making product suggestions. #3 is that I always give my customers references to support the information I’ve given them, including books, online articles, websites (such as, referrals to Naturopathic doctors that I know, etc. One of the best resources I recommend to my customers is the free web site, which provides full monographs on every currently available prescription drug, including known interactions with supplements and a complete list of adverse reactions a particular prescription drug is reported to have. You would be amazed at how often a health condition or symptom that a customer is asking me about is listed as a common side effect of a drug they have been prescribed.

  • Chad Henry

    Hi, you commented somewhere that raw garlic can interfere with the action of some HIV meds. My partner is HIV positive, and loves garlic. How can we find out which meds don’t react well with garlic. And what about grapefruit? Thanks.