Independent Tests and Reviews of Vitamin, Mineral, and Herbal Supplements

Rare but Serious GLP-1 Side Effect

GLP-1 medications have been linked to a rare but serious brain condition caused by a vitamin deficiency. Get the details about this and the vitamins and minerals of concern with GLP-1 medications.

Cholesterol-Lowering Statins Affected by Green Tea

Levels of cholesterol-lowering statin drugs, such as atorvastatin (Lipitor), can be affected by green tea. Get the latest information in our Green Tea Review, which includes our tests and Top Picks for green tea.

Amazon Supplements Fail Label Claims

Seven out of 20 berberine supplements sold on Amazon failed to contain their claimed amounts of berberine, with one product containing none. Get the details by product and see our Top Picks for berberine.

The Hidden Sweetener Found in Some Protein Powders

Thaumatin is a natural sweetener and flavor enhancer found in some protein powders and other supplements. Learn about its pros and cons and see our Top Picks for no-calorie or low-calorie sweeteners.

How to Reduce Microplastics in Your Tea

Plastic tea bags can release microplastics into your tea, but a new study showed a quick thing you can do to reduce the plastic by more than 75%. Find out in our Green Tea Review, which includes our Top Picks for green tea in bags, loose tea, matcha, bottled tea, and supplements.

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B Vitamins & Complexes
Magnesium
Psyllium & Fiber Supplements
Vitamin D
Water Filter Pitchers

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Find the best supplements and foods — based on independent tests of quality.

Best NAD+ Booster Supplements? See our Top Picks

OmegaXL Review: Does It Really Work for Joint and Muscle Pain?

Most Seaweed Snacks & Foods Fail Tests — But We Found a Winner

Some Colostrum Supplements Fail to Deliver

Supplements to Take or Avoid When Using a GLP-1 Drug

365 Whole Foods Market Ashwagandha Recalled

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Popular Product Reviews

B Vitamin Supplements

Dark Chocolates, Cocoa Powders and Supplements

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Extra Virgin Olive Oil

Green Tea Supplements and Drinks

Magnesium Supplements

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Probiotics

Vitamin C

Vitamin D Supplements

Product Updates

Rare but Serious GLP-1 Side Effect

Cholesterol-Lowering Statins Affected by Green Tea

Amazon Supplements Fail Label Claims

The Hidden Sweetener Found in Some Protein Powders

How to Reduce Microplastics in Your Tea

Upcoming Reviews

Expert Answers to Popular Questions

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Ratings of ConsumerLab

Clinical Updates

Passionflower for a Testosterone Boost?

Lower NAD Levels: Is Age Really the Reason?

Cholesterol-Lowering Statins Affected by Green Tea

Rare but Serious GLP-1 Side Effect

The Hidden Sweetener Found in Some Protein Powders

Recalls & Warnings

New Green Nutrition Warned by FDA After Hidden Steroid Found in Product

365 Whole Foods Market Ashwagandha Recalled Due to Salmonella Risk

Hidden Tadalafil Found in Green Lumber Natural Fuel for Men

Ultimate Forza Male Supplement Recalled Due to Hidden Drugs

Flintstones Complete Multivitamins Recalled in Canada

Clinical Updates

Passionflower for a Testosterone Boost?

Lower NAD Levels: Is Age Really the Reason?

Cholesterol-Lowering Statins Affected by Green Tea

Rare but Serious GLP-1 Side Effect

The Hidden Sweetener Found in Some Protein Powders

Recalls & Warnings

New Green Nutrition Warned by FDA After Hidden Steroid Found in Product

365 Whole Foods Market Ashwagandha Recalled Due to Salmonella Risk

Hidden Tadalafil Found in Green Lumber Natural Fuel for Men

Ultimate Forza Male Supplement Recalled Due to Hidden Drugs

Flintstones Complete Multivitamins Recalled in Canada

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