Reviews and Information for Inactive Ingredients
Inactive Ingredients
Find out about the safety and regulation of added ingredients in supplements, protein drinks and bars and more, including cellulose, lactose, magnesium stearate, methylcellulose, microcrystalline cellulose, polyethylene glycol (PEG), povidone, sorbitol, starch, and xylitol, coloring agents such as Blue 1 Lake, D&C Yellow No. 5, Red 40 Lake, Yellow 5 Lake and Yellow 6 Lake and sweeteners such as aspartame, sucralose, maltodextrin.
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CL Answer
Are the inactive ingredients I see listed on my supplement label necessary? Are they dangerous?
Learn more about the inactive ingredients found in supplements, including coloring agents, and their safety.
Product Review
Joint Health Supplements for Pets Review (Glucosamine, Chondroitin, MSM & Boswellia)
See Which Pet Supplements for Joint Health Passed Our Tests and Which Didn't!
CL Answer
Should I be concerned about supplements that contain Polysorbate 80? Is it safe?
Find out if polysorbate 80 is a safe ingredient in supplements.
Product Review
Toprol XL vs. Generic Metoprolol Succinate Extended-release (ER) Tablets Review Article
Choose the Best Blood Pressure Medication. Find Out Why Some Generic Blood Pressure Medications Are Not the Same as the Original & May Increase Blood Pressure or Have Other Disturbing Side Effects.
Product Review
Zinc Supplements and Lozenges Review
Find the Best Zinc Supplements and Lozenges. Have a Cold? See CL's Top Picks Among Zinc Supplements and Lozenges.
CL Answer
Titanium dioxide is listed as an ingredient in my supplement. Is it safe?
Titanium dioxide in supplements might have you concerned. Learn more about titanium dioxide - FDA status and evidence from studies on cancer.
CL Answer
I read an article stating that some of the ingredients in Centrum multivitamins may be dangerous or toxic. Is that true?
Learn more about the safety of ingredients in Centrum, including binders, fillers, and coloring agents.
CL Answer
What is magnesium stearate, what is it made from, and is it dangerous?
Learn more about magnesium stearate and its safety, based on evidence from clinical studies.
CL Answer
What is Lutigold Lutein? And why is the capsule of one brand of lutein so much larger than that of another brand, if the amount of lutein on the label is the same?
Learn more about lutein supplements like Lutigold, FloraGlo, and XANGOLD, and understand the difference in capsule sizes.
Clinical Update
11/29/2022
Tooth Stains from Food Colorants
Find out which food colorants appear to increase staining of the teeth in the Coloring Agents section of our Inactive Ingredients Review.
CL Answer
Which ingredients should toothpastes and other dental products contain, and which should be avoided?
Learn about ingredients you want in your toothpaste, mouthwash and other dental products and which ingredients you may want to avoid.
CL Answer
What is the best sunscreen based on safety and efficacy?
We’ve boiled down the latest research about mineral and chemical sunscreens, including product tests, to help you choose the best sunscreen (which will depend on whether you expect to be in or out of the water). We also list popular sunscreens that have, or have not, been found to contain cancer-causing compounds (benzene and benzophenone).
Product Review
Turmeric and Curcumin Supplements and Spices Review
See Our Top Picks Among Turmeric Products
CL Answer
Does the talc added to Centrum Silver and other vitamins pose a risk of cancer?
Find out if talc, an inactive ingredient in many vitamins and supplements, is safe to consume, and learn about asbestos in talc and cancer risk and USP-grade talc vs. food-grade talc and cosmetics-grade talc. ConsumerLab.com's answer explains.
Product Review
L-Lysine Supplements Review
Read L-Lysine Labels Carefully. Some Can Fool You.
Product Review
Cinnamon Supplements and Spices Review
CAUTION: Some Cinnamon Products High in Toxin. See Which Passed or Failed and our Top Picks!
Product Review
Psyllium Fiber Supplements Review
Find the Best Psyllium Fiber Supplement and Avoid Lead.
CL Answer
Should I be worried that my supplement contains "caramel coloring IV"? I've heard that it has been linked to cancer.
Learn more about caramel coloring IV, including evidence from studies on cancer.
CL Answer
Is it better to use a powdered product that you mix with liquid than to take a pill? I was told that the vitamins will be more completely absorbed. Is that true?
Learn more about taking supplements & multivitamins in powder or tablet form, including tips on how to get the most from your supplement.
Clinical Update
10/31/2023
Can B-12 cause allergic reactions?
Although rare, vitamin B-12 can cause allergic reactions, but so can “inactive” ingredients in B-12 and other supplements. For details see the Risks of B-12 section of our Vitamin B-12 Review, which includes our Top Picks for B-12.
Clinical Update
5/25/2019
Concern With a Colorant
Titanium dioxide is a common white colorant in foods and supplements. A recent study in mice, however, suggests that it may affect the gut. For details, see the updated Titanium Dioxide section of the Inactive Ingredients/Excipients article.
Clinical Update
5/11/2021
Whitener In Many Pills May Not Be Safe
Titanium dioxide, which is commonly used to whiten pills, is not safe according to the European equivalent of the FDA. Find out why in our Review Article about Inactive Ingredients.
Clinical Update
12/07/2021
Can a Natural Colorant Cause Adverse Effects?
A CL member recently asked if purple carrot powder in his supplement might have caused symptoms such as chest tightness and headache. Find out in our updated article about Inactive Ingredients/Excipients.
Clinical Update
3/31/2023
Phosphate Additives in Food
Are phosphate additives, such as trisodium phosphate and dicalcium phosphate, a health concern? Find out in our article about Inactive Ingredients in supplements and foods.
Clinical Update
10/14/2022
Cancer-Causing Sweetener?
Acesulfame potassium is a sweetener in some of the products that we have tested. A CL member asked if it can cause cancer. Find out in the Sweetening agents section of our Inactive Ingredients/Excipients in Supplements Review Article.
Clinical Update
8/18/2023
Benzene in Supplements?
Can sodium benzoate, a preservative used in supplements and foods, be converted to benzene, a toxic compound? Find out what a recent study showed in our article about Inactive Ingredients.
Also see our articles about benzene in sunscreens and deodorants.
Clinical Update
8/22/2023
Sodium Benzoate and Benzene
Vitamin C can promote the conversion of sodium benzoate, a preservative, to benzene, a toxic chemical. Should you be worried about consuming products such as lemon juice (a source of vitamin C) preserved with sodium benzoate? Find out in the Preservatives section of our article about Inactive Ingredients.
CL Answer
What is UC-II and does it help joints?
What is UC-II (undenatured type 2 collagen - InterHealth Nutraceuticals) and do clinical studies show that it works for joint health?
CL Answer
I have type 2 diabetes. Should I be concerned about ingredients like maltodextrin and maltitol that are found in some protein bars and drinks?
Learn more about maltitol and maltodextrin and their effects on blood glucose levels for people with type 2 diabetes.
CL Answer
I read that turmeric may be a GI irritant. I have GI problems and wonder if I should avoid turmeric and curcumin?
Find out if turmeric/curcumin supplements can cause gastrointestinal irritability.
CL Answer
Is soy in supplements good or bad for you?
Find out about the health benefits and/or safety concerns related to soy constituents (including soy isoflavones, soy protein, soy lecithin, and soybean oil), and learn how you can avoid soy in supplements if necessary.
Product Review
Probiotic Supplements Review (Including Pet Probiotics)
Probiotics: See What They Really Contain and Our Top Picks
CL Answer
Does AHCC (active hexose correlated compound) have anticancer or antiviral benefits, and is it safe?
Learn about AHCC (active hexose correlated compound), including whether it is beneficial for liver, pancreatic, or prostate cancer, chemotherapy-related side effects, or the flu, and if it is safe.
Product Review
Taurine Supplements Review for People, Dogs, and Cats
Find the Best Taurine Supplements. Learn When to Use Taurine and Which Supplement is Best.
Product Review
Alginate Supplements Review (For Reflux)
See Our Top Pick Alginate Supplements For Reducing Symptoms of Gastroesophageal Reflux (GERD)
CL Answer
Are enteric coated supplements better than non-enteric coated ones?
Learn about the pros and cons of enterically coated supplements, including ingredient absorption,safety and price.
CL Answer
What are trace minerals and do I need them?
Trace minerals include boron, chromium, copper, iodine, iron, manganese, molybdenum, nickel, zinc, and others. Find out what they do, how much of each trace mineral you should be getting, and who's most likely to be deficient in these minerals.
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.
CL Answer
I take levothyroxine (Synthroid), a thyroid hormone to treat hypothyroidism. Are there supplements or foods I should avoid, or be taking, due to this drug?
Is taking certain supplements and hypothyroidism medications bad? Learn which supplements can interact with thyroid hormone medications like levothyroxine (Synthroid), thyroid hormone levels, and laboratory tests.
Product Review
Weight Loss Supplements Review (7-Keto DHEA, Forskolin and Stimulant Blend Supplements)
Choose the Best Weight Loss Supplement. Be Careful With Weight Loss Supplements — Few Pass Quality Testing and Safety Review.
Product Review
Vision Supplements Review (with Lutein, Zeaxanthin & AREDS2 Formulas)
Find the Best Vision Supplement Based Our Tests
CL Answer
Some websites claim that synthetic vitamin C in supplements may be a combination the active "L" form and the inactive "D" form of ascorbic acid. Is that true? Should I be concerned?
Learn more about the forms of vitamin C.
CL Answer
The probiotic I am taking looks pink. Does this mean it is spoiled or no longer "active"?
Find out if a pink probiotic is safe, since they are usually white.
CL Answer
Tablets I purchased are becoming "crumbly" after a few weeks and are easy to break. Is there a problem with this supplement?
Should you be concerned if your supplement tablets have started to crumble? Learn more including the best way to keep pills from getting soft.
CL Answer
I heard the S-form of alpha-lipoic acid is bad for me. Why is it in my supplement?
Learn more about R-form alpha-lipoic acid and S-form alpha-lipoic acid and their activity, as described by experts at ConsumerLab.com.
Product Review
Huperzine A Supplements Review
Choose the Best Huperzine A Supplement. CL Tests Reveal the Best Huperzine A Supplements for Memory.
CL Answer
Are L-carnosine supplements helpful and safe?
Learn about the potential health benefits of L-carnosine, as well as possible safety concerns, drug interactions and cost.
News Release
December 02, 2010
ConsumerLab.com Finds Lower-priced Resveratrol Supplements Pass Tests While Some Higher-priced brands flunk
WHITE PLAINS, NEW YORK — DECEMBER 2, 2010 — ConsumerLab.com reported today that tests of supplements containing resveratrol — a compound promoted as "life-extending" — revealed that two products provided only 43.4% and 86.
CL Answer
Supplements That May Be Needed When Following a Gluten-Free Diet
Find out if supplements such as folate, vitamin B-12, niacin, thiamin, iron, vitamin D, and/or fiber are needed when following a gluten-free diet. Also learn how to find gluten-free supplements on ConsumerLab.com.
CL Answer
Do sea moss and carrageenan have health benefits? Are there risks?
Sea moss is promoted for thyroid health, boosting immunity, improving gut health, and other uses. Find out if it works and learn about possible side effects of sea moss and its constituent, carrageenan.
Product Review
Breast Enhancement Supplements Review Article
Do Breast Enhancement Supplements Really Work? See the Evidence For and Against Breast Enhancement Supplements.
CL Answer
Do arnica pills, gels, creams, or sprays reduce bruising, pain, or swelling?
Find out if arnica pills, gels, creams, or sprays can reduce bruising, pain, or swelling, help with varicose veins, or muscle pain after exercise.
CL Answer
What are the best bug sprays to prevent tick and mosquito bites? Is the insecticide permethrin safe to use?
Find out how permethrin sprays differ and which can be used on sheets and sleeping bags versus clothing
News Release
March 17, 2008
As problems surface, Consumerlab.com and the people's pharmacy ask FDA to disclose differences between generic and original drugs
WHITE PLAINS, NEW YORK AND DURHAM, NORTH CAROLINA — MARCH 17, 2008 — An investigation by ConsumerLab.
CL Answer
What are the health benefits of manuka honey, and is it safe?
Manuka honey health benefits, how it differs from common, store-bought honey, safety, evidence for using manuka honey for wounds, sore throat and cough, constipation and more.
Recalls & Warnings
May 14, 2016
Xylitol in Supplements Poses Danger for Dogs
On May 12, 2016, the FDA warned consumers that xylitol, a popular sweetener found in chewable vitamins, chewing gum, breath mints, toothpaste and a variety of other products, is toxic to dogs.
Recalls & Warnings
February 13, 2013
FDA Warns Maker of Weight Loss and Whey Protein Supplements For Manufacturing Violations and Misbranding
January 25, 2013, the FDA issued a warning letter to dietary supplement manufacturer SciLabs Nutraceuticals, following a facility inspection which found the company's dietary supplements and supplement ingredients, including N-Large 2, Flo-Gard AB, Nitrogen Glutamine capsules, Nutritech nutritional ...