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Supplements for Brittle Nails -- healthy nails


There are many supplements marketed for strengthening nails, but the only significant evidence to-date is for supplementing with biotin (vitamin B-7). ('s tests of biotin supplements are found in the Product Review of B Vitamins, including its Top Pick among biotin supplements.) A small, but controlled, study among women with brittle nails found that a daily dose of 2,500 mcg of biotin for 6 to 9 months increased nail thickness by 25% and reduced the tendency of nails to split (Columbo, J Am Acad Dermatol 1990). Biotin does not, however, further strengthen healthy nails. Also, be aware that high doses of biotin can interefere with certain medications and laboratory tests, including tests used to diagnose thyroid disease and heart attacks, so be sure to tell your doctor if you are taking biotin.

A study in Brazil suggested a benefit for brittle nails from a collagen supplement. However, there was no placebo control in the study, making the findings questionable. Women in the study consumed 2.5 grams per day of bioactive collagen peptides (BCP, VERISOL) dissolved in water for 24 weeks. Nail growth was reported to have increased by 12% and the frequency of broken nails decreased by 42% compared to the period before collagen treatment. There was no significant change in nail roughness (i.e., ridging and grooves) (Hexsel, J Cosmet Dermatol 2017).

Some preliminary studies also suggest improvement in brittle nails supplementing with 10 to 30 mL daily of colloidal silicon (silicic acid, trademarked Silicol) or 10 mg daily of orthosilicic acid. Adequate intake of vitamins and minerals facilitates nail health, but there is no evidence that normal nails are affected by supplementing with gelatin, cystine, L-methionine,  keratin, pantothenic acid, salt, millet, yeast, or chromium, or with formulas containing these ingredients (Scheinfeld J Drugs Dermatol 2007).

As noted in the Magnesium Supplements Review, some research suggests that people who have soft, flaky nails that are inclined to break or split may have reduced blood levels of magnesium.

As discussed in the Iron Supplements Review, brittle nails can be a symptom of iron deficiency anemia.

Soft, thin nails that break easily have been associated with vitamin C deficiency, as noted in the Vitamin C Supplements Review. (Vitamin C also helps improve iron absorption).

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November 6, 2018

if a vitamin has lead. How many mcg of lead per pill is safe?
December 4, 2018

Hi Arlete - Lead is a toxic heavy metal. Although adults (other than pregnant women) can tolerate 70 mcg per day from total intake (i.e., all food, water, and air), it is best to avoid unnecessary exposure as lead can accumulate in bones (replacing calcium).

When ConsumerLab tests products, it uses the State of California's Prop 65 limits for lead in dietary supplements of 0.5 mcg per recommended daily serving in products with a single serving weight of less than 5 grams which are not marketed for children – and slightly higher limits for products containing large amounts of minerals or whole herbs. Products marketed with single serving weights of 5 grams or more, and products which are marketed for children have different limits, as set by Prop 65. See the "How Products Were Evaluated" page for the Multivitamins Review ( for more details about limits for lead.

October 25, 2017

Perhaps more than one mineral is needed for strong nails. In my case, adding magnesium to my diet was the answer to my brittle nails. It also totally stopped my migraines.

October 25, 2017

My dermatologist started me on Genadur, which is applied like a nail polish at night. It absorbs into the nail. My nails were heavily damaged from acrylic nails but now they look great. The only problem is the price which is about $300 per bottle— outrageous. It’s a prescription that isn’t covered by insurance. It lasts about six months. I figured I spent that much on manicures with the fake nails in six months so it’s a trade off. I now have healthy nails which makes me happy.

October 25, 2017

My husband had very thin and brittle nails. Our doctor offered no advice saying that some people just have brittle nails. A friend suggested we read the book, "Why Stomach Acid is Good for You", which prompted him to start taking Betaine HCl with high protein meals. From what we've read, as we age our bodies produce less and less stomach acid which makes it difficult for the body to digest and absorb protein. Betaine HCl aids that digestion. His nails are quite normal now.
October 26, 2017

Thank you for sharing your experience with this, Rebecca.

September 8, 2017

Hi, which enzymes do you take, please? Can you share the brand, please?

September 1, 2017

I used to have thin brittle nails years ago. I started using multi enzymes along with other supplemments. My nails grew very strong within 3 months. I didn't know why this was happening and thought my particular vitamins were the cause. I quit taking the enzymes and my nails became thin again. I have been taking them for years now, and have switched brands many times. My nails are still very strong and grow rapidly and I break a nail maybe once or twice a year. I have to cut them back about every 2 to 3 weeks. I believe that we are not getting the nutrition from our food because of lack of enzymes among other reasons. I recommend them to everyone.

October 25, 2017

Hi Julie, I was wondering if you could give me the name of the multi enzymes that you are taking. I would love to try them and see if they would work for me.

August 28, 2017

After RNY gastric bypass, my nails were incredibly soft and broke constantly. I tried biotin which helped somewhat. After I added vitamin K2 my nails fairly rapidly went back to their normal strong condition. At some point I tried cutting the dose in half (because of high cost). My nails became softer and more breakable. I am now taking the higher dose again and my nails are great.

August 23, 2017

I have found consistent use of Bone Restore formula by Life Extension makes my nails stronger. Without the mineral formula my nails become soft and thin with constant tears and splits. I only use 1/2 of the recommended daily dose (I use 2 capsules/dose=4). That equates to only 350 mg supplemental calcium (in a couple different forms), along with added D, magnesium, boron, K, zinc, manganese and silicon. I also have teeth sensitivity, and this formula prevents that as well. I have used straight calcium for my teeth in the past, but this formula is much better overall and makes a notable difference in the nails, and possibly hair as well.

August 23, 2017

I have been taking Omega 3 for years. Besides lowering my triglycerides it also strengthen
my nails.

September 6, 2017

Yes, taking fish oil with high DHA strengthened my nails after a couple of months. Been taking it for several years.

August 23, 2017

I added vitamin K to my supplements a few months ago because I read it helps send the calcium to the bones. I can't tell how that is working but my nails are stronger and longer than they have ever been. They used to break all the time.
August 23, 2017

Interesting! Thank you for sharing your experience Ellen. You can read more about the evidence for vitamin K and bone health in the "What It Does" section of the Vitamin K Supplements Review:

August 23, 2017

I've had nail problems as well as micro cuts near the nail during the winter months. The one thing that has helped is vitamin C. I'm talking real vitamin C not ascorbic acid. I take 240 mg daily of Nutrigold organic whole food vitamin c gold. I was taking 4000 mg of Costco vitamin C but it didn't do the job. Nails are strong and no more of those painful little cuts in the winter. Go figure. Heard this tip on a radio show on supplements.
August 24, 2017

Thank you for sharing your experience with this, Jerry. We've now added information about vitamin C (and iron) in the answer above.

Susan 15427
August 21, 2017

A friend with some anxiety would peel the nail with his fingers or teeth when nervous (had done so since a child). He had used BioSil for some years; but, quit last year. He noticed this winter that his nails would split in odd directions and never across; but usually down in the center (I have a photograph if needed for proof). After 30-45 days use of BioSil (one "000" capful daily), his nails returned to normal. He still has the occasional anxiety...

October 6, 2018

In this ConsumerLab discussion, 3 ConsumerLab customers, Susan, Pamela and Ann mention about good experiences from BioSil.

I have been using BioSil drops for years. I can't tell is it of benefit as I use so many other supplements as well, but at least it does not seem to do any harm.

I read most BioSil reviews at Amazon and iHerb websites and I found no reason not to continue buying.

One can find several BioSil clinical studies at PubMed website!

ConsumerLab should test BioSil capsules & drops and tell us does it make any difference, which one to buy?
I haven't bought the capsules because they are much more expensive to use compared to drops.

August 21, 2017

I agree with Ann 15413 comments about BioSil. I think it is actually doing something with my hair and fingernails. My wrinkles haven't disappeared nor has my skin seemed more elastic (how would I know?) but my nails and hair seem to have accelerated in growth and strength after 45 days of taking 2 BioSil capsules per day. I've been told the silica source is sand... odd. I'll keep trying it for about a year and see if this just wasn't a coincidence. I wasn't taking this to correct a problem, so I haven't 'cured' any ailment. Their claim is that it promotes your body to create its own collagen.

August 20, 2017

I have taken MSM (Methylsulfonylmethane) for years because it strengthens my nails. About 4 years ago, I stopped because I thought it was just another false claim by the snake oil industry. Lo, my nails began to split and weaken. So after a one-year hiatus, I resumed. Nails are once again strong. Not very scientific, I know, but that's been my experience. I have no financial ties to any business that markets or manufactures MSM.
August 21, 2017

Hi Antonia - We are not aware of any clinical studies showing MSM improves nail strength, but thank you for sharing your experience with this. You can see our tests of products containing MSM in the Joint Supplements Review:

August 20, 2017

I've been taking collagen supplements for over a year now. Prior to that my nails were so soft and brittle that I never was able to grow them out. Since taking collagen they have become hard as rocks and grow so fast that I have to file them down every few days. I take collagen one, two and three.

October 25, 2017

Same here. Collagen has been a miracle supplement for me. My nails tend to be very brittle. Perhaps something is missing in my diet, although I eat plenty of vegetables, chicken, and fish. I've been taking BioCell collagen for over two years now and my nails have never been stronger. If I stop taking it for a couple of months, the problems come back.

August 20, 2017

FWIW I went on a low carb hi fat (LCHF) diet last Feb and have had no brittle nails since. Recently just let my fingernails grow to see what would happen. They got to the longest I have ever experienced, and I finally had to trim them because they were getting in the way. Age spots have also begun to fade.

August 20, 2017

I had brittle nails for years until I started taking 400mg magnesium daily. It also cured my lifetime of migraines.
August 24, 2017

Hi Elizabeth - Thank you, we've now added information about this to the Answer. There is also evidence that magnesium may help for migraines:

August 20, 2017

I have found that BioSil (I use the drops) has made a great difference in the strength of my fingernails. I am a skeptic about manufacturers' claims, but in this case I "came to scoff and stayed to pray". Maybe it' s not a solution for everyone, but the label suggests that different doses can affect nails, hair, and bones. It's Choline-stabilized orthosilicic acid , manufactured by Natural Factors.

August 20, 2017

I've never taken collagen or any supplement for my joints or fingernails but here's a personal anecdote for everyone (Vegetarians or vegans might not appreciate this story as much):
I noticed that after eating the edible parts of chicken bones, from roasted chicken or the like, that within about two weeks my finger and toenails were appreciably stronger, I'd not sure if they grew more rapidly but that is quite possible as well.
(By the "edible parts" I mean mostly the "knuckles", and I of course prefer organic meats, especially when things like this are concerned; organ meats, bone, bone marrow, all places where it would seem that toxins would build up.)
I considered taking some supplements recently because of a nagging joint issue but I'm reading the label there was so much shellfish involved I shied away because I might have recently developed a sensitivity to those, I wonder if anyone else has experience with those supplements glucosamine, collagen etc.

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