Marie Claire UK Marie Claire UK
  • Fashion Fashion
      • Fashion
        • View all Fashion
        • Fashion Trends
        • Shopping
        • Watches and Jewellery
        • Fashion News
  • Beauty Beauty
      • Beauty
        • View all Beauty
        • Fragrance
        • Hair
        • Make Up
        • Skincare
        • Nails
        • Marie Claire Beauty Awards
  • Health Health
      • Health
        • View all Health
        • Fitness
        • Nutrition
        • Female Health
        • Wellbeing
  • Life Life
      • Life
        • View all Life
        • Opinions
        • Travel
        • Sustainability
        • Weddings
        • Money & Work
        • Competitions
  • Culture Culture
      • Culture
        • View all Culture
        • TV and Film
        • Celebrity News
        • Books
        • Royal News
  • Vouchers Vouchers
      • Clothing
        • View all Vouchers
        • Mint Velvet
        • Karen Millen
        • H&M
        • nobody's child
        • ASOS
        • ARKET
        • MANGO
      • Designer Clothing
        • View all Vouchers
        • Reiss
        • THE OUTNET
        • SSENSE
        • Mytheresa
        • Liberty London
        • Selfridges
        • Farfetch
      • Accessories
        • View all Vouchers
        • AllSaints
        • Aspinal of London
        • Charles & Keith
        • River Island
        • FitFlop
        • Kate Spade
        • Vagabond
      • Jewellery
        • View all Vouchers
        • Pandora
        • Abbott Lyon
        • Goldsmiths
        • Beaverbrooks
        • Astrid & Miyu
        • Swarovski
        • Angara Jewellery
      • Beauty
        • View all Vouchers
        • Sephora
        • Cult Beauty
        • Space NK
        • Dyson
        • Clarins
        • Look Fantastic
        • Clinique
      • Activewear
        • View all Vouchers
        • Lululemon
        • Gymshark
        • Sweaty Betty
        • Nike
        • adidas
        • New Balance
        • Helly Hansen
  • NEWSLETTER Signup to our newsletter
  • logoCreated with Sketch.
    Marie Claire Newsletter

    Celebrity news, beauty, fashion advice, and fascinating features, delivered straight to your inbox!


    By submitting your information you agree to the Terms & Conditions and Privacy Policy and are aged 16 or over.

    You are now subscribed

    Your newsletter sign-up was successful


    An account already exists for this email address, please log in.
    Trending
    • Women in Sport 2026
    • Marie Claire Masters
    • Spring Summer 2026
    • Nail Trends 2026
    • Best Investment Bags
    • Best Perfumes
    • Digital Issues
    • Women Who Win
    1. Health and Fitness

    These 15 supplement ingredients carry serious health risks

    According to a new report

    By Marie Claire
    Published 28 July 2016 In Features

    When you purchase through links on our site, we may earn an affiliate commission. Here’s how it works.

    colourful pills in separate petri dishes.jpg
    colourful pills in separate petri dishes.jpg
    (Image credit: VOISIN/PHANIE/REX/Shutterstock)
    • Facebook
    • X
    • Pinterest
    Share this article
    Join the conversation
    Follow us
    Add us as a preferred source on Google
    Subscribe to our newsletter

    According to a new report

    Despite their popularity in pharmacies, health food stores, and even hospitals, over-the-counter dietary supplements are not regulated in a way that ensures their safety and efficacy, says a new article published today by Consumer Reports. These products have the potential to be contaminated with dangerous bacteria or to differ widely from what their labels claim them to be. And in some cases, they deliberately contain ingredients that can cause cancer, organ damage, cardiac arrest, and other serious health problems.

    The report warns consumers to stay away from 15 such ingredients, found in supplements sold in major retail stores across the United States. These products may be especially harmful for people with pre-existing medical conditions, the authors say, or who take other supplements or drugs (prescription or over-the-counter) that could trigger dangerous interactions.

    The ingredients, and their claimed benefits, include:

    •Aconite, used for inflammation, joint pain, or gout

    You may like
    • A grapefruit and some vitamins I'm a Nutrition Scientist Who's Seen That Supplement Stacking Is Trending—Here's My Honest Take
    • Best sports supplements from iHerb Trust Me, I'm a Nutritionist: These Are the Best Sports Supplements for Energy, Endurance and Recovery
    • A bag of fresh groceries 5 Longevity Trends Experts Say Aren't Worth Your Time or Money

    •Caffeine powder, used for weight loss, increased energy, and athletic performance

    •Chaparral, used for weight loss, inflammation, colds, rashes, and infections

    Marie Claire Newsletter

    Celebrity news, beauty, fashion advice, and fascinating features, delivered straight to your inbox!

    By submitting your information you agree to the Terms & Conditions and Privacy Policy and are aged 16 or over.

    •Coltsfoot, used for cough, sore throat, laryngitis, and asthma

    •Comfrey, used for cough, heavy periods, stomach problems, and chest pain

    •Germander, used for weight loss, fever, arthritis, gout, and stomach problems

    What to read next
    • Health freelancer Georgia Brown: Biomel Gut Supplement Review Move Aside, Fibremaxxing—I Tested This Viral Fibre Supplement For A Month and The Results Blew Me Away
    • A close up shot of a woman smiling Don't Ignore Your Bone Health—It's A Key Longevity Marker For Women. 8 Simple Ways To Protect Yours
    • A flat lay of some of the best protein powders for women, including travel sachets from Form Nutrition, Hermosa, Innermost, MyProtein and more On the Hunt for the Best Protein Powder for Women? 13 a Health Editor Uses to Boost Satiety and Build Muscle

    •Greater Celadine, used for stomach aches

    •Green tea extract powder, used for weight loss

    •Kava, used for anxiety and insomnia

    •Lobelia, used for respiratory problems and for quitting smoking

    •Methylsynephrine, used for weight loss, increased energy, and athletic performance

    •Pennyroyal oil, used for breathing problems and digestive disorders

    •Red yeast rice, used for high cholesterol and heart disease

    •Yohimbe, used for low libido, erectile dysfunction, depression, and weight loss

    These ingredients can also be listed by other names. Their aliases, and the specific risks associated with each ingredient, are published on ConsumerReports.org and available free of charge.

    (Image credit: VOISIN/PHANIE/REX/Shutterstock)

    Some of the ingredients have been shown to cause side effects such as vomiting, nausea, dizziness, impaired driving, and breathing problems. Others have been associated with liver damage, cancer, and serious heart problems. And several of them can interact with other medications, says Ellen Kunes, Consumer Reports Health Content Team Leader. The quality of the ingredients and the length of time they’re taken for can also affect the severity of these risks.

    'Say I want to lower my cholesterol, and I’ve read that red yeast rice can help do that,' Kunes told Health.com. “But I may already take a prescription statin for that. If I take both of them together, the effects can be magnified—and the results can be dangerous. That’s the bottom line we want to get across to consumers.'

    The report also found that shoppers can’t trust pharmacists or retail staff to alert them to the potential harms of these products: When the Consumer Reports staff sent secret shoppers into 60 stores around the country to ask about these ingredients, many store employees gave information that was “either misleading or flat-out wrong.”

    And even if you avoid these 15 most alarming ingredients, there’s no guarantee that any over-the-counter supplement is safe, or that it contains what it’s supposed to. Many consumers don’t realise that supplements are regulated by the government as a food and not as a drug, says Kunes—which means that companies don’t have to go through stringent tests before putting their products on shelves.

    (Image credit: VOISIN/PHANIE/REX/Shutterstock)

    'These products don’t always contain what they claim to,' she says. 'That could mean you’re just wasting your money on something harmless—but the reality is, a lot of it is not harmless.' The industry is much larger than government inspections can keep up with, she adds. 'Many times, the FDA only gets involved after they get a report that there’s a problem.'

    In the article, Consumer Reports’ chief medical adviser notes that there are certain situations in which a person might truly benefit from a supplement—including those who are pregnant, have dietary restrictions, take certain drugs, or have chronic health conditions. But these people should only take the type and dosage recommended by their doctor. They may even be able to take a prescription-strength supplement, which must meet the same safety and efficacy standards as other prescription drugs.

    In most other cases, says Kunes, supplements aren’t necessary. 'Eating a balanced diet, getting lots of fruit and vegetables, exercising regularly and getting enough sleep, lowering stress—these are the things that are going to truly help you feel healthier,' she says. 'We recommend getting your health from food and from healthy habits, rather than popping a pill.'

    From the Editors at Health

    Marie Claire
    Social Links Navigation

    The leading destination for fashion, beauty, shopping and finger-on-the-pulse views on the latest issues. Marie Claire's travel content helps you delight in discovering new destinations around the globe, offering a unique – and sometimes unchartered – travel experience. From new hotel openings to the destinations tipped to take over our travel calendars, this iconic name has it covered.

    Read more
    A grapefruit and some vitamins
    Nutrition I'm a Nutrition Scientist Who's Seen That Supplement Stacking Is Trending—Here's My Honest Take
    Best sports supplements from iHerb
    Nutrition Trust Me, I'm a Nutritionist: These Are the Best Sports Supplements for Energy, Endurance and Recovery
     
     
    A bag of fresh groceries
    Wellbeing 5 Longevity Trends Experts Say Aren't Worth Your Time or Money
    Health freelancer Georgia Brown: Biomel Gut Supplement Review
    Nutrition Move Aside, Fibremaxxing—I Tested This Viral Fibre Supplement For A Month and The Results Blew Me Away
     
     
    Latest in Health and Fitness
    Arsenal footballer and Lioness Chloe Kelly
    Health and Fitness Women in Sport 2026: Featuring Chloe Kelly, Elite Beauty Products, Grand Prix 2.0 and So Much More
    Eva Syti, yoga coach, ARC sauna leader and breathwork practitioner
    Wellbeing Most People Think They're Manifesting Correctly—But Usually Miss These 3 Essential Steps
     
     
    A woman lying on the floor scrolling on her phone
    Female health If You're Frazzled, Overworked and At Your Limit, These 5 Science-Backed Tips Can Help Avoid Burnout
    Health freelancer Anna Bartter treating friendship as a wellness habit: at a concert, at a bar, and with friends
    Wellbeing I Treated Friendship Like a Wellness Habit for Two Months—It Changed My Mental Health More Than I Expected
     
     
    Latest in Features
    The long hair trend and the post-bob era
    Hair I’ve Spent Two Years Growing My Bob—Turns Out, There's a Reason Long Hair Is Trending
    Arsenal footballer and Lioness Chloe Kelly
    Health and Fitness Women in Sport 2026: Featuring Chloe Kelly, Elite Beauty Products, Grand Prix 2.0 and So Much More
     
     
    Mischa Anouk Smith on an astrology travel trip to Türkiye, where she got engaged less than 24 hours after a birth chart reading.
    Travel I Let Astrology Plan My Holiday—Less Than 24 Hours Later, I Was Engaged
    Eva Syti, yoga coach, ARC sauna leader and breathwork practitioner
    Wellbeing Most People Think They're Manifesting Correctly—But Usually Miss These 3 Essential Steps
     
     
    logoCreated with Sketch.
    • Site Archive
    • Contact Future's experts
    • Contact us
    • Terms and conditions
    • Advertise with us
    • Privacy policy
    • Cookies policy
    • About us
    Add as a preferred source on Google Add as a preferred source on Google

    Marie Claire UK is part of Future plc, an international media group and leading digital publisher. Visit our corporate site.

    © Future Publishing Limited Quay House, The Ambury, Bath BA1 1UA. All rights reserved. England and Wales company registration number 2008885.