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CL Answer

Do any supplements help relieve stress?

Are there actually supplements for stress relief and panic attacks? Learn more about holy basil, fish oil, L-theanine, and ginseng.

Product Review

Ashwagandha Supplements Review

Find the Best Ashwagandha Supplement. Only 56% of Ashwagandha Products Pass Tests.

Ashwagandha supplements reviewed by

Product Review

GABA Supplements Review

Does GABA Work As a Supplement?

Product Review

L-Theanine Supplements Review

Touted for Stress Relief, Do L-Theanine Supplements Work?

CL Answer

What is GABA (gamma-aminobutyric acid)? Is it beneficial for stress, anxiety, insomnia or other conditions, and is it safe?

Find out about GABA (gamma-aminobutyric acid), including if it's beneficial for insomnia, epilepsy, stress and anxiety, high blood pressure and building muscle, and learn if taking GABA supplements is safe.

Older women sitting calmly on a couch with her hands behind her head and her eyes closed

CL Answer

Adrenal Fatigue and Adrenal Support Supplements: Do they work and are they safe?

Find out what's really in supplements for adrenal support and adrenal fatigue, including herbal adrenal support supplements and bovine derived adrenal support supplements. Find out if they really work and if they are safe.'s answer explains.

Adrenal Fatigue and Adrenal Support Supplements -- Tired Woman Falling Asleep at Her Desk

CL Answer

What are the health benefits of holy basil extract?

Learn about the health benefits of holy basil leaf extract. See the clinical evidence for and against holy basil extract for lowering blood sugar in people with type 2 diabetes, reducing anxiety and stress, boosting the immune system, and reducing the pain and inflammation of arthritis.'s answer explains.

Holy Basil for Diabetes, Anxiety and Stress? -- Holy basil leaf and pills

CL Answer

What is hydrogen water? Is it beneficial for alertness, athletic performance, arthritis or other conditions, and is it safe?

Find out if hydrogen water has benefits with regard to alertness, side effects of radiotherapy in cancer patients, metabolic syndrome, athletic performance, rheumatoid arthritis, liver disease, and other conditions, and learn if it is safe to use.

Portable hydrogen water generator

Product Review

Holy Basil Supplements Review

Find the Best Holy Basil (Tulsi) Supplements. Tests and Reviews of Popular Holy Basil Supplements & CL's Top Pick.

Holy Basil Supplements Reviewed by

CL Answer

What is Protandim and does it really work?

What is Protandim and does it really work? Can Protandim reduce oxidative stress? ConsumerLab's answers discusses Protandim's effectiveness, reviews and studies.

Does Protandim Work? -- Bottle of Protandim

Product Review

Valerian Supplements Review

Choose the Best Valerian Supplement. Strength and Contamination Vary Widely Among Popular Valerian Brands.

Valerian Supplements Reviewed by

CL Answer

Rhodiola and ashwagandha are both promoted to help with stress and anxiety. Is it safe to take them at the same time?

Find out if it is safe to take ashwagandha and rhodiola together. Both herbs are promoted to help with stress and anxiety, but may also lower blood pressure and have other side effects.'s answer explains.

Man in Light Blue Comparing Supplement Bottles

Product Review

Probiotic Supplements Review (Including Pet Probiotics)

Probiotics: See What They Really Contain and Our Top Picks

Clinical Update


Probiotics for Stress?

Did taking probiotics reduce stress in recent studies? Find out in the Stress section of our Probiotics Supplements Review.

Also see: Do any supplements help relieve stress?

Clinical Update


Ashwagandha for Stress?

A recent study found that an ashwagandha extract reduced stress, anxiety, and depression, but dose and type of extract appears to matter. See the details in the Stress section of our Ashwagandha Supplements Review, which includes our Top Picks among ashwagandha supplements.

Also see: Do any supplements help relieve stress?

CL Answer

Will pregnenolone help slow down aging or reduce chronic pain?

Learn more about the steroid hormone pregnenolone, including its effects in the body and on aging and chronic pain.

Elderly couple yoga pose in sunshine

CL Answer

Does Alpha Brain really improve memory, focus and cognition?

Find out if Alpha Brain really improves memory, focus and cognition. See the clinical evidence and get details about Alpha Brain ingredients, as well as potential side effects and drug interactions.'s answer explains.

Bottle of Alpha Brain capsules

CL Answer

Are antioxidant supplements good or bad for you?

Learn more about whether antioxidants like astaxanthin, beta-carotene, coenzyme Q10, curcumin, resveratrol, selenium, vitamin A, vitamin C and vitamin E are safe and if they help prevent chronic diseases.

Can Antioxidants Cause You to Die Sooner? -- antioxidant supplements and carrots

Product Review

NAC (N-Acetyl Cysteine) Supplements Review

Choose the Best N-Acetyl Cysteine Supplement. See Our Tests of Popular NAC Supplements and Top Picks for Quality and Value.

N-acetyl cysteine (NAC) supplements tested by

Product Review

CBD Oils, Softgels, Gummies, Creams & Salves Review

See How Much CBD and THC We Found in Products.

CL Answer

Do any supplements help with pancreatitis? Do any cause pancreatitis?

Find out if supplements including digestive enzymes, antioxidants, or medium-chain triglycerides are beneficial for chronic pancreatitis, and learn which supplements might worsen symptoms.

Person with pancreatitis holding their abdomen

CL Answer

How does Athletic Greens’ AG1 compare to multivitamins and Greens powders? Is AG1 worth it?

ConsumerLab reviews the ingredients in AG1, its safety and possible side effects, and how AG1 compares to other products.

A pouch of AG1 on white background

CL Answer

I'm taking Lumiday, a supplement to improve mood. It seems to help me but is it safe?

Lumiday info including side effects, drug interactions and reviews. Lumiday is a supplement marketed to improve mood.

Product Review

Saffron Supplements Review

See How Saffron Supplements Compare and What They Do

Clinical Update


Ashwagandha for Stress and Anxiety

Can ashwagandha decrease symptoms of anxiety and lower levels of a stress hormone? See what a new study found in the Anxiety, Stress and Insomnia section of the Ashwagandha Supplements Review. Also see our Top Pick for ashwagandha.

Clinical Update


Saffron for Stress?

Can saffron reduce stress and anxiety? See what a recent study found in the What It Does section of our Saffron Supplements Review, which includes our Top Picks among saffron supplements.

Also see: Do any supplements help relieve stress?

CL Answer

Can any supplements reverse gray hair?

Nearly 75% of adults aged 45 to 65 are affected by gray hair. Learn about what causes gray hair and find out if any supplements can help.

A young woman shows gray hair on her head on a white background

Product Review

Fish Oil, Krill Oil, and Algal Oil Omega-3 (DHA & EPA) Supplements Review

See Our Omega-3 Top Picks and Avoid Rancid Fish Oils.

Fish Oil and Other Marine Oil Supplements Reviewed by

CL Answer

Do glutathione supplements work to prevent aging or for other conditions?

Do glutathione supplements help with aging or other conditions such as cancer and diabetes?

Spoon filled with glutathione supplement capsules and held over a white plate

CL Answer

What are the health effects of apigenin and is it safe?

Apigenin, a flavonoid compound, is promoted for sleep, depression, cancer, and other conditions. Find out if it works and if it's safe.

Apigenin capsules on wooden spoon along with a chamomile flower

Product Review

Vitamin C Supplements Review

Find the Best Vitamin C Supplements

Vitamin C Review 2023

CL Answer

What are the best supplements for depression and anxiety?

Best natural supplements for depression and anxiety, including the evidence for fish oil, vitamin D, probiotics, and herbal supplements for depression such as curcumin (from turmeric) and saffron.

Best Supplements for Depression and Anxiety -- sad young woman sitting on couch, looking toward the window

Clinical Update


Fish Oil and Stress

A new study shows that fish oil may slightly blunt some of the effects of mental stress. Get the details, plus our quality ratings of 74 supplements, in the updated Fish Oil and Omega-3 Fatty Acid Supplements Review >>

Clinical Update


Does Ashwagandha Lower Stress?

A widely available ashwagandha extract was recently tested for its ability to reduce stress, at two different doses. Find out if either worked in the What It Does section of the Ashwagandha Supplements Review. Also see our Top Pick for ashwagandha.

Clinical Update


Lutein for Stress?

Supplementing with lutein can help some people protect against macular degeneration of the eye. A new study suggests it may also reduce stress. For details, see the "What It Does" section of the Review of Vision Supplements with Lutein and Zeaxanthin (which includes our tests of products) >>

Clinical Update


Fish Oil for Stress?

A recent study investigated whether taking fish oil rich in the omega-3 fatty acid EPA would reduce chronic stress. See the results in the "What It Does" section of the Fish Oil Supplements Review >>

Clinical Update


CBD for Post-traumatic Stress Disorder (PTSD)?

Can moderate doses of CBD help people with post-traumatic stress disorder? See the latest clinical findings in the What It Does section of the CBD Oil and Hemp Extract Supplements Review. Also see our Top Picks for formulations of CBD.

Clinical Update


Ashwagandha for Stress?

Ashwagandha is widely promoted to reduce stress, but does it really work? See what a recent study found in the What It Does section of our Ashwagandha Supplements Review. Also see our Top Picks for ashwagandha.

Clinical Update


Help for Stressed Dogs?

Does CBD reduce stress in dogs during car rides? See what a recent study showed in our CBD Review, and see our Top Picks among products for pets.

Clinical Update


Ashwagandha for Stress?

Does ashwagandha supplementation reduce stress? See what a new study found in the What It Does section of our Ashwagandha Supplements Review.

Clinical Update


L-Theanine for Stress?

Can L-theanine supplementation reduce stress during demanding tasks? See the latest evidence in the What It Does section of our L-Theanine Supplements Review.

CL Answer

What is Brain Bright and can it really improve memory or cognition?

Learn more about BrainBright, including clinical studies on memory and cognition, safety, and cost.

CL Answer

What are the side effects of ashwagandha supplements?

Learn about the safety and side effects of ashwagandha supplements, including headache, sleepiness, upset stomach, blood pressure and more.'s answer explains.

ashwagandha side effects

CL Answer

Which supplements reduce the risk of stroke? Which increase the risk of stroke?

Find out which supplements (may help reduce the risk of stroke/might increase the risk of stroke.)

Stroke Spelled on Wooden Blocks Against Blue Background

CL Answer

Which supplements help with Raynaud's phenomenon?

Raynaud's phenomenon may be helped by some supplements. Learn more about fish oil, Gingko biloba, and ginseng.

Supplements for Raynaud's Phenomenon -- woman standing outside in snow, with cold, red hands

CL Answer

Which supplements have been shown to be helpful for autism?

Find out which supplements may help reduce symptoms of autism, including multivitamins, probiotics, and melatonin.

Bottle and Pills Spread Out on Blue Background

CL Answer

How do the COVID-19 vaccines compare in terms of efficacy, safety and side effects? How, when and where do I get the COVID-19 vaccine?

Find out how the COVID-19 vaccines from Pfizer and Moderna compare and learn how when and where you can get the COVID-19 vaccine.

Older woman getting an injection

Clinical Update


Dark Chocolate for Mood?

A recent study investigated the effects of consuming dark chocolate on mood. The effect depended on cocoa level. See the results in the Mood and Stress section of our Dark Chocolate and Cocoa Review. Also see our Top Picks among dark chocolate bars and cocoa products.

Clinical Update


Saffron for Mood?

Does saffron extract improve mood in people feeling down and anxious or stressed? See what a new study found in our article about Supplements for Depression and Anxiety.

Clinical Update


Probiotic for Anxiety?

A number of studies have evaluated probiotics for reducing anxiety, stress, and depression. See the results of the latest study in the What It Does section of the Probiotic Supplements Review. Also see our Top Picks among probiotics.

Clinical Update


Ashwagandha Improves Memory

An 8-week study among men and women with mild cognitive impairment found ashwagandha root extract to improve many aspects of cognitive function compared to placebo. Studies have shown a range of benefits with ashwagandha, particularly in reducing stress and anxiety, although studies have been small. For details, see the "What It Does" section of the Ashwagandha Supplements Review >>

Clinical Update


Does Dark Chocolate Improve Mood?

A recent study evaluated whether eating dark chocolate improved mood and reduced levels of cortisol, a stress hormone. See the results in the What It Does section of the Dark Chocolate and Cocoa Review. Also see our Top Picks among products.

Clinical Update


Dark Chocolate & Depression?

Are people who consume dark chocolate less likely to be depressed? Find out what a recent study showed in the Mood and Stress section of the Dark Chocolates and Cocoa Powders Review. Also see our Top Picks for dark chocolates and cocoa powders.

Clinical Update


L-Theanine for Sleep and Cognition?

Several studies have evaluated whether a single dose of L-theanine (found in green tea) can reduce stress and anxiety. A new study has evaluated the effect of L-theanine when taken daily for several weeks. See the results in the What It Does section of the L-Theanine Supplements Review. Also see our top choices for L-Theanine.

Clinical Update


Ashwagandha for Better Sleep?

Ashwagandha, which is often used for anxiety and stress, was recently tested in people with insomnia. Did it help them fall asleep? Find out in the What It Does section of the Ashwagandha Supplements Review. Also see our Top Pick for ashwagandha.

Clinical Update


Does MSM Help Joints and Muscles?

MSM (methylsulfonylmethane) is commonly in supplements for joint and muscle pain, although the evidence behind it has been limited. Its effectiveness in reducing pain, muscle damage, and oxidative stress was recently evaluated in people running a half-marathon. See the results in the "What It Does" section of the Joint Health Supplements Review (Glucosamine, Chondroitin, MSM, and Boswellia), which includes our Top Picks among products.

Clinical Update


Cacao Flavanols for Mood?

Did drinking a beverage containing cacao flavanols improve mood in a recent study? Find out in the Mood and Stress section of our Dark Chocolates and Cocoa Powder Review, which includes our Top Picks for dark chocolate and cocoas.

Clinical Update


L-Theanine for Fatigue?

Did drinking a beverage containing L-theanine, with or without CBD, reduce fatigue? See what a recent study showed in the Stress, sleep and cognition section of our L-Theanine Review, which includes our Top Picks for L-theanine.

Also see: Which supplements help to improve energy and decrease fatigue?

CL Answer

After taking a curcumin supplement, I started getting chronic diarrhea which went away when I stopped taking it. Can curcumin supplements cause diarrhea?

Learn more about the side effects of curcumin supplements, including diarrhea and other gastrointestinal discomfort.

Turmeric and Diarrhea

Product Review

CoQ10 and Ubiquinol Supplements Review

Find the Best CoQ10 and Ubiquinol Supplements and Learn How They Differ

CoQ10 2024

CL Answer

Do any supplements or lifestyle changes reduce the symptoms of tinnitus? Is it true that some supplements can cause tinnitus?

Learn which supplements can ease tinnitus, including melatonin and pine bark extract. Understand which may actually cause tinnitus.

Word blocks spelling out “tinnitus”

Clinical Update


Latest Supplement Recommendations

New draft recommendations on vitamin and mineral supplement use were published this week by the U.S. Preventive Services Task Force. The recommendations apply only to healthy adults without nutritional deficiencies. They focus only on the use of supplements for the prevention of cardiovascular disease and cancer at doses not exceeding tolerable upper intake levels. The recommendations are based on existing science and are generally consistent with information already presented in's Product Reviews.  We have summarized the recommendations below, with links to more information in's reports:

- Beta-Carotene and Vitamin E:  Supplementation with either does not provide a benefit. Vitamin E does not pose a risk of harm, but beta-carotene increases the risk of lung cancer in people at risk for lung cancer.

- Other Single Vitamins, Minerals, Pairs, and Multivitamins: There is inadequate evidence regarding a benefit or a risk of harm.

The task force stressed that at excessive doses (above tolerable upper intake levels) there is evidence of harm with supplementation, such as with vitamin A and vitamin D

CL Answer

Do any supplements help with fatty liver disease? Are some diets more beneficial than others?

Find out if supplements such as vitamin E, fish oil, milk thistle, curcumin, choline, probiotics, vitamin D, reishi mushroom, or extra virgin olive oil are beneficial for fatty liver disease and learn which diet (Mediterranean, ketogenic, DASH, or fasting diets) seems to have greatest benefit.

Overweight man holding his right side near his liver

Product Review

Dark Chocolates, Cocoa & Cacao Powders, Nibs, and Supplements Review -- Sources of Flavanols

Is Your Chocolate or Cocoa Healthful or Toxic? Find the Best Dark Chocolate, Cocoa Powder and Cocoa Supplements Based On Our Tests.

Product Review

Prebiotic Supplements Review

You Can't Tell How Much Fiber Is Really In Most Prebiotics Without Testing

Prebiotics 2024 Expanded Review

CL Answer

Do any supplements naturally suppress appetite and help with weight loss?

Learn which natural ingredients can suppress appetite and find if these natural appetite suppressants help with weight loss.

Container of natural appetite suppressant supplement with measuring tape and scale in background

CL Answer

What is TUDCA (tauroursodeoxycholic acid)? Does it have any proven health benefits, and is it safe?

TUDCA information, including its potential health benefits, safety, possible interactions, and cost.

What is Tudca - white capsules poured out of container

CL Answer

Can any vitamins or minerals help prevent or reduce canker sores or cold sores?

Find out which, if any, supplements, including iron, L-lysine, monolaurin, olive leaf extract, vitamin B-12, and zinc, may be beneficial for canker sores or cold sores.

Lip of woman with a cold sore

Product Review

Vision Supplements Review (with Lutein, Zeaxanthin & AREDS2 Formulas)

Find the Best Vision Supplement Based Our Tests

CL Answer

What is Noopept? Can it really improve memory and cognition, and is it safe?

Learn more about Noopept, including results from clinical studies on cognition, safety, and dosage.

CL Answer

Can drinking coffee prevent gallstones? Can supplements help?

Information about the impact coffee has on gallstone disease. Plus, supplements that have been proposed to help with gallstone pain.

Coffee and Gallstones -- coffee in cup and coffee beans

CL Answer

Is echium oil a good alternative to fish oil? I am allergic to fish.

Echium oil as an alternative to fish oil. Learn more for those with fish allergies, including information on omega-3 fatty acids.

Fish Oil Tablets and Liquid on White Background

CL Answer

Do magnesium supplements, like Magtein, help memory or protect against Alzheimer's disease?

Magtein, and other magnesium supplements, may help memory and protect against Alzheimer's disease.

Memory 1400

CL Answer

I'm considering taking vitamin K for my bones, but I take blood thinner (anticoagulant) medication. Is there a problem taking both?

Learn more about vitamin K, including info on interactions with blood thinners such as Coumadin and Jantoven, its effects on bones & impact on clotting.

CL Answer

My HDL (good) cholesterol level is low. Should I take niacin to raise my HDLs?

Learn more about niacin and find out if it can raise HDL ("good") cholesterol levels.

Vitamin B3 Blister Packs

CL Answer

Does Bacopa extract improve memory, mood, or sleep? Is it safe?

Find out if bacopa improves memory and cognition, mood or sleep, and whether it's been shown to be helpful in people with Alzheimer's disease or dementia. Plus, learn about the safety and common side effects of bacopa.

Bacopa for Memory and Cognition -- Bacopa leaves and powder

CL Answer

Does urolithin A reduce age-related muscle decline or improve osteoarthritis?

Find out if urolithin A may improve age-related muscle decline and learn about its safety.

Older couple walking together to exercise

CL Answer

Which supplements reduce hearing loss?

Can supplements such as alpha-lipoic acid, magnesium, N-acetyl-cysteine, folate or vitamins B-12, C and/or E help prevent or improve symptoms among people with hearing loss due to excessive noise or aging? Find out what the clinical evidence shows, and learn whether Advanced Hearing Formula, a supplement marketed for ear health, is likely to help.

Older man holding his hand up to his ear due to hearing loss

CL Answer

Are There Supplements That Help Treat POTS (Postural Orthostatic Tachycardia Syndrome)?

Find out which supplements and lifestyle changes may be helpful for people with Postural Orthostatic Tachycardia Syndrome (POTS).


CL Answer

How are you staying healthy during the coronavirus pandemic?

Tips for staying healthy during the coronavirus (COVID-19) pandemic. Tips from ConsumerLab members for maintaining physical health, mental health and social well-being during COVID-19.

Staying Healthy During the Coronavirus Pandemic -- Couple at Home, Looking Out the Window

Product Review

Melatonin Supplements Review

Trouble Sleeping? See CL's Tests of Melatonin Supplements and Top Picks.

Melatonin Review 2024

News Release

March 09, 2023

L-Theanine Supplements Reviewed by ConsumerLab. Top Pick Chosen.

  White Plains, New York, March 9, 2023 —L-theanine supplements are often promoted to reduce stress and improve sleep and cognition.

CL Answer

Is it possible to take too much vitamin C?

Find out the daily value of vitamin C, along with possible side effects of excessive vitamin C intake. ConsumerLab explores the topic of proper vitamin C supplement usage, and why taking too much can be harmful.

Bottles of vitamin C pills

News Release

February 23, 2023

Best GABA Supplements Identified by ConsumerLab

White Plains, New York, February 23, 2023 — GABA (gamma-aminobutyric acid) supplements are claimed to have a "calming" effect, and are often promoted to reduce stress and insomnia and improve cognitive performance.

CL Answer

Do any supplements help for ulcerative colitis?

Find out what supplements & vitamins can help with ulcerative colitis, such as VSL#3, curcumin, aloe or boswellia.

Woman Grabbing Stomach Due To Abdominal Discomfort

CL Answer

What are the health benefits of zinc carnosine, also called polaprezinc, and is it safe?

Find out if zinc carnosine is beneficial for any GI conditions, including stomach ulcers, Helicobacter pylori infection, taste disturbances, aspirin-induced small-bowel injury and oral mucositis, and learn if it is safe.

Zinc carnosine supplements in wooden spoon in front of oysters

CL Answer

Does ergothioneine help prevent age-related problems such as impaired cognition, Alzheimer’s disease, Parkinson’s disease or cataract, and is it safe?

Learn about ergothioneine and its potential use for cognitive impairment, dementia, Alzheimer's disease, Parkinson's disease, cataract, or kidney disease, as well as its safety and cost of supplements containing this ingredient.

Various types of mushrooms that contain ergothioneine in a wooden bowl on a wooden countertop

Recalls & Warnings

February 24, 2023

Bountiful Charged with “Review Hijacking,” False Advertising of Nature’s Bounty Supplements on Amazon

On February 16, 2023, the Federal Trade Commission (FTC) charged The Bountiful Company (formerly NBTY), whose brands include Nature’s Bounty and Sundown, with deceptively using Amazon reviews and badges (such as “#1 Best Seller” and “Amazon’s Choice”) from its ...

Product Review

Rhodiola Rosea Supplements Review

Do Rhodiola Supplements Help With Depression and Anxiety? Find Out and See Which Rhodiola Supplements Provide the Best Quality & Value.

Rhodiola Supplements Reviewed by

Product Review

Ginseng Supplements Review

Find the Best Ginseng Supplement. Key "Ginsenosides" Found to Range 10-Fold Across Products.

Ginseng Supplements Reviewed by ConsumerLab

Product Review

Vitamin E Supplements Review

Find the Best Vitamin E Supplement. Tests and Reviews of Popular Vitamin E Supplements & CL's Top Picks.

Vitamin E Supplements, Cream, and Oil Tested by

CL Answer

Do any supplements help prevent or treat a cold?

Are there supplements that can help prevent or treat cold symptoms? Learn more about zinc, probiotics, vitamin C and more.

Supplements for Colds: Zinc, Echinacea & More -- Couple with cold, sitting on couch blowing their noses

CL Answer

I take omeprazole (Prilosec), a proton pump inhibitor, to reduce stomach acid. Are there supplements I should avoid, or be taking, due to this drug?

Supplement interactions with proton pump inhibitor (PPI) drugs like omeprazole (Prilosec) and Nexium.

CL Answer

Is it true that there are bits of plastic in drinking water, specialty salts, or other foods and beverages? How concerned should I be?

Microplastics are tiny pieces of plastic that can end up foods and beverages. Learn about microplastics found in drinking water and specialty salts.'s answer explains.

Microplastics in water, plastic bottle of water pouring water into glass

News Release

April 03, 2020

Tests of Holy Basil Supplements Show 63% Fail on Quality -- ConsumerLab Tests Reveal the Best and Worst Holy Basil Supplements

White Plains, New York, April 3, 2020 — Holy basil supplements are promoted to reduce stress and anxiety, lower blood sugar, and strengthen the immune system.

CL Answer

Do any supplements or diets help prevent or treat osteoporosis?

If you have osteoporosis, you may be interested in supplements or diets for bone health. Find out which can increase bone strength and density.

Doctor discussing osteoporosis with older female patient

CL Answer

My doctor told me to stop taking supplements because my kidney function was low. After stopping, my kidney function returned to normal. Can taking a lot of supplements really damage the kidneys?

Find out which supplements may damage your kidneys. ConsumerLab explores possible kidney side effects of supplements including chromium, creatine, and vitamin C.

Can Supplements Really Damage Your Kidneys? -- Woman with kidney pain

CL Answer

Can taking too much vitamin B-12 be dangerous? The label on my B-complex states it contains 50,000% of the Daily Value!

Find out the daily value for vitamin B-12 and the potential side effects of taking too much B-12. ConsumerLab explains why taking too much vitamin B-12 can be harmful.

The danger of taking too much vitamin B-12 -- bottle of vitamin B-12 with pills on the table spelling out 'B-12'

CL Answer

Which supplements and lifestyle changes improve sleep, and which cause insomnia?

Find out which vitamins may help you sleep and learn if any vitamins or supplements can cause insomnia.

CL Answer

Do any supplements help for irritable bowel syndrome (IBS)?

IBS supplements may help reduce irritable bowel symptoms such as pain, diarrhea and constipation. Supplements include probiotics, melatonin, and flaxseed.

Supplements for IBS? -- Women With Stomach Pain

CL Answer

What are CoQ10 side effects?

CoQ10 side effects, such as nausea, headache, and insomnia, and how you can reduce the occurrence of CoQ10 side effects.'s answer explains.

CoQ10 2024

CL Answer

Which supplements may help with PCOS (polycystic ovarian syndrome)?

Many supplements are promoted to help treat symptoms of PCOS (polycystic ovarian syndrome), but do they really work? See the clinical evidence for inositol (myo-inositol and D-chiro-inositol), alpha lipoic acid, vitamin B-12, folic acid, vitamin D and more.

Supplements for PCOS

CL Answer

Do supplements help with Parkinson’s disease treatment or prevention?

Learn what has been shown with vitamins D and E, niacin, CoQ10, melatonin, creatine, SAMe, NAC, valerian, CoQ10, and CBD, as well as with coffee and the Mediterranean and MIND diets for treating and/or preventing Parkinson's disease.

Elderly man with parkinsons holding trembling hand while eating

CL Answer

What is lumbrokinase, does it have heart benefits, is it safe, and what should you look for, or avoid, in a lumbrokinase supplement?

Lumbrokinase is marketed as promoting healthy circulation and supporting heart health. Find out how and if lumbrokinase supplements actually work, possible safety concerns, and what to consider when choosing a lumbrokinase supplement.

Capsules of lumbrokinase poured onto a black table

CL Answer

What are the health benefits of bovine colostrum and is it safe?

Bovine colostrum is promoted for boosting immunity, preventing and treating diarrhea, and improving gut health, but does it really work? See the clinical evidence for bovine colostrum, including doses that have been used, as well as safety concerns, cost considerations, and the difference between regular bovine colostrum and hyperimmune bovine colostrum.

Bovine colostrum powder and capsule supplements

CL Answer

Butyrate Supplements for Gut Health: Does butyric acid really work and is it safe?

Can butyrate supplements improve gut health or help reduce symptoms of irritable bowel syndrome (IBS) or Crohn's disease? Find out what the clinical evidence shows, learn about the different forms of butyrate, including sodium butyrate, calcium-magnesium butyrate, and tributyrate, and get details about products such as BodyBio Sodium Butyrate and Healus Complete Biotic Tributyrin, dosage, safety and cost.

Butyrate Supplements

Product Review

Turmeric and Curcumin Supplements and Spices Review

See Our Top Picks Among Turmeric Products

CL Answer

Is drinking coffee good or bad for heart health?

Learn more about coffee and caffeine, its safety, if it's good for you, how much coffee is too much and its impact on your heart.

CL Answer

Do any supplements, foods or lifestyle modifications help with brain function, like memory and cognition?

Find out which supplements help improve memory, brain function and cognition, including fish oil, some B vitamins, cocoa, and curcumin. ConsumerLab's answer explains the evidence for supplements promoted to help with brain function and cognition.

Supplements for Memory -- doctor holding a model of a brain and fish oil capsule

CL Answer

Do hair loss supplements, such as Viviscal, Hair La Vie, and Nutrafol, or topical essential oils work?

Vitamins and supplements that may help with hair loss and thinning, including saw palmetto, beta-sitosterol, protein, iron, and vitamin D.

Supplements for Hair Loss -- woman looking at hairbrush

Recalls & Warnings

January 12, 2023

FDA Warns Two Sellers Promoting CBD to Treat COVID-19

On January 10, 2023, the FDA issued warning letters to two companies following a review that found statements made on the companies’ websites to be drug claims because they promoted the cannabidiol (CBD) products to prevent or treat COVID-19.

Recalls & Warnings

May 04, 2023

FDA Warns MedoLife for Promoting Homeopathic Products to Treat COVID-19, Cancer

On April 19, 2023, the FDA issued a warning letter to Medolife Rx D/B/A MedoLife Corp., AELIA Inc. and Queanta Inc.

Recalls & Warnings

August 25, 2022

Oregon’s Wild Harvest Warned by FDA for Manufacturing Violations

On July 8, 2022, the FDA issued a warning letter to Oregon’s Wild Harvest, Inc.

News Release

May 31, 2018

ConsumerLab Identifies the Best Valerian Supplements -- Strength, Quality and Cost Vary Widely Among Popular Brands

White Plains, New York, May 31, 2018 — Valerian is often promoted as a sleep aid and to help with anxiety. But does it really work, and if so, which products are best? To find out, ConsumerLab recently purchased and tested popular valerian supplements sold in the U.S.

Recalls & Warnings

September 21, 2023

Moor Herbs, Inc Warned for Manufacturing Violations, Drug Claims

On August 1, 2023, the FDA issued a Warning Letter to Moor Herbs, Inc.

Recalls & Warnings

August 14, 2020

The Green Herb and New Genesis Health Warned for Manufacturing Violations

On July 31, 2019, the FDA issued a warning letter to Davis Ventures, Inc.

News Release

February 23, 2017 Reveals Best and Worst B Vitamin Supplements and Why Current Labels Often Mislead

White Plains, New York, February 24, 2017 — B vitamins and complexes are popular supplements, but labels often mislead, says a new report from which tested, reviewed, and compared 49 supplements from the U.S.

Recalls & Warnings

February 22, 2021

FDA Warns Sellers of St. John's Wort

On February 18, 2021, the FDA issued warning letters to two companies following reviews of the companies' websites, which found statements made about the companies' St. John's Wort products to be drug claims. These products include St.

News Release

August 13, 2015

Feeling Stressed? Reviews the Evidence for L-Theanine and Test Popular Products

White Plains, New York, August 21, 2015 — L-theanine is often promoted to reduce stress, and for conditions such as ADHD — but does it really work? recently reviewed the evidence and purchased popular brands of L-theanine to test their quality.

Recalls & Warnings

October 29, 2019

Chinese Herbal Supplement May Raise PSA

Use of a Chinese herbal supplement appears to have significantly increased the PSA (prostate specific antigen) level in a man treated for prostate cancer, erroneously suggesting a recurrence of the cancer (Abel, J Am Osteopath Assoc 2019).

News Release

January 06, 2015

Only 25% of Ashwagandha Supplements Pass Review

White Plains, New York, January 6, 2015 —"It's very hard to find a good ashwagandha supplement," notes Tod Cooperman, M.D., President of, the health product testing company which recently completed evaluations of ashwagandha herbal supplements.

Recalls & Warnings

June 02, 2018

FDA Warns Seller of Cough Suppressant & Grape Seed Supplements

On March 29, 2018, the FDA issued a warning letter to Yoder's Good Health Products following a facility inspection which found a number of the company's products, including Respiratory & Cough Formula and Life Drops to be adulterated because they were prepared, packed, or ...

Recalls & Warnings

November 24, 2018

Dangerous Drug In Supplements for Pain and Anxiety

On November 20, 2018, the FDA announced it has issued warning letters to two companies for the illegal marketing of products labeled as dietary supplements that contain the opioid-like drug tianeptine.

Recalls & Warnings

August 25, 2018

Thirty-Two Children's Homeopathic Products Recalled

On August 22, 2018, King Bio issued a recall of 32 homeopathic products for children because some have have tested positive for microbial contamination.

Recalls & Warnings

May 22, 2018

FDA Warns Companies Selling "Sun Protection" Supplements

On May 18, 2018, the FDA issued warning letters to four companies selling supplements for sun protection because statements made on product labels, websites and in marketing materials were found to be drug claims, which are not permitted for dietary supplements. 

Recalls & Warnings

July 18, 2017

Seller of "Super Strength Prostate Formula," Acai Berry Supplements & More Warned for Drug Claims

On June 30, 2017, the FDA issued a warning letter to Nature's Health Company, LLC, following a facility inspection and review of the company's website, www.natureshealthcompany.

Recalls & Warnings

November 02, 2009

FTC Charges Marketers with Baseless Weight-Loss Claims

On November 2, 2009 the U.S. Justice Department, at the Federal Trade Commission’s request, filed suit today in federal court in a case affecting consumers nationwide.

Recalls & Warnings

November 18, 2011

FDA Warns Maker of Milk Thistle and L-Carnitine Supplements of Serious Violations

The U.S. FDA posted a Warning Letter to CJ Labs (Miami, Florida) dated November 1, 2011 regarding serious violations of Good Manufacting Practices in the production of its Milk Thistle and L-Carnitine supplements.

Recalls & Warnings

August 05, 2016

Seller of Fertilix Warned By FDA

On July 22, 2016, the FDA issued a warning letter to CellOxess LLC, following a review of the company's websites, social media pages and marketing literature which found statements made about Fertilix Preconceptual, Fertilix Low Dose and Fertilix Max to be drug claims.

Recalls & Warnings

December 07, 2012

Antioxidant Protandim Supplement Recalled Due To Risk of Metal Fragments

On December 5, 2012, LifeVantage Corporation issued a voluntary recall of dietary supplement Protandim, the Nrf2 Synergizer, due to the potential for contamination with small metal fragments. The recall includes Protandim products sold in the U.S. and Japan between July and November 2012.

News Release

September 27, 2012 Reveals How Much Caffeine is in Energy Drinks -- Also Finds Some Drinks and Dietary Supplements Don't Contain Claimed Amounts of B Vitamins

White Plains, New York — September 27, 2012 — Energy shots and drinks are promoted to keep you alert and energized, attributing their effects to special formulas often "packed with B vitamins and nutrients to make it last," as a commercial for 5-hour Energy proclaims.

News Release

March 07, 2008 finds most vitamin C supplements pass quality tests but one short on ingredient and some exceed tolerable levels

WHITE PLAINS, NEW YORK — MARCH 7, 2008 — reported test results today for a wide variety of vitamin C supplements. Vitamin C is the top-selling single vitamin in the U.S., with sales of $863 million in 2006 according to Nutrition Business Journal.

Recalls & Warnings

March 17, 2004

Marketers of “Focus Factor” and “V-Factor” Fined for Advertising Claims

On March 17 , 2004 the Federal Trade Commission (FTC) reported that the marketers of “Focus Factor,” a dietary supplement that purports to improve concentration, and “V-Factor,” a supplement that purports to enhance sexual performance, have agreed to settle charges that they made numerous ...

Recalls & Warnings

February 14, 2013

Maker of Antioxidant and Anti-Aging Supplements Warned For Manufacturing Violations

On January 10, 2013, the FDA issued a warning letter to dietary supplement manufacturer Consolidated Marketing Unlimited, Inc.

Recalls & Warnings

January 07, 2002

Liver Toxicity with Kava

As announced in a December 19, 2001 letter to healthcare professionals, The Food and Drug Administration (FDA) is investigating whether the use of dietary supplements containing kava (also known as kava kava or Piper methysticum) is associated with liver toxicity.

Recalls & Warnings

February 22, 2012

"Japan Weight Loss Blue" Pills Dangerous According to FDA

On February 18, 2012, the U.S. Food and Drug Administration (FDA) advised consumers not to purchase or use “Japan Weight Loss Blue,” a product for weight loss sold on various websites, including

Recalls & Warnings

May 30, 2015

Seller of Supplements for Herpes, Prostate Cancer & More Warned for Drug Claims

On May 7, 2015, the FDA issued a warning letter to Strictly Health Corporation, following a review of the company's websites which found statements made about FENVIR, Prosta Pep and Tonalin brand CLA to be drug claims.

Recalls & Warnings

May 26, 2015

Skin Measurement Device Used to Select Nutritional Supplements Not Approved for This Use, FDA Warns

On May 8, 2015, the FDA issued a warning letter to ZYTO Technologies, Inc.

News Release

March 14, 2005 reports on vitamin C supplements — Test Results for 29 Products Reported Along with Information on Use

WHITE PLAINS, NY — MARCH 14, 2005 — reported test results today for a wide variety of vitamin C supplements purchased at retail. Vitamin C is the top-selling single vitamin in the U.S., with sales of $770 million in 2003 according to Nutrition Business Journal.

News Release

August 28, 2003

Some problems persist with ginseng supplements but overall quality improves according to — Test results published online today

WHITE PLAINS, NY — August 28, 2003 — In contrast to its testing three years ago in which nearly 60% of Asian and American Ginseng supplements were found to have significant problems, testing of recently purchased products by ConsumerLab.

Recalls & Warnings

January 03, 2004

FDA to Prohibit Sales of Dietary Supplements Containing Ephedra

On December 30, 2003, the U.S. Food and Drug Administration (FDA) issued a consumer alert of its forthcoming determination that dietary supplements containing ephedra present an unreasonable risk of illness or injury, and should not be consumed.

Recalls & Warnings

March 25, 2002

FDA Advises Consumers of Risk of Severe Liver Toxicity with Kava

On March 25, 2002 the U.S. Food and Drug Administration (FDA)issued a Consumer Advisory, as well as a letter to health care providers, advising of the potential risk of severe liver injury associated with the use of kava-containing dietary supplements.

Recalls & Warnings

March 03, 2006

FDA Requests Seizure of More Supplements Containing Ephedrine Alkaloids

On February 24, 2006, the U.S. Food and Drug Administration (FDA) announced that the U.S.

Recalls & Warnings

February 20, 2013

Cold, Flu and Stress Supplement Company Warned For Adulteration, Drug Claims And More

On October 5, 2012, the FDA issued a warning letter to dietary supplement manufacturer Wholistic Herbs, Inc. following a facility inspection which found the company's products, including At-Ease, Morning Calm, Aller-Ban, Stomach Flu, Kold & Koff, Kold Sore, and L.

Recalls & Warnings

October 06, 2004

False Claims Made by Marketer of Cortisol-related Weight-Loss Supplements According to FTC

On October 6, 2004, the Federal Trade Commission (FTC)charged marketers of two dietary supplements with claiming, falsely and without substantiation, that their products can cause weight loss and reduce the risk of, or prevent, serious health conditions.

Recalls & Warnings

April 11, 2008

Twelve Dietary Herbal Supplements Recalled -- Possible Health Risk Associated with Ephedra, Aristolochic Acid and Human Placenta

On April 10, 2008, the FDA posted a recall notice issued the same day from Herbal Science International, Inc. (AKA Jen-On Herbal Science International, Inc.).