Are Brittle Nails a Sign of a Vitamin or Mineral Deficiency?

Are Brittle Nails a Sign of a Vitamin or Mineral Deficiency?
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Note: The U.S. Food and Drug Administration (FDA) does not approve supplements for safety or effectiveness. Talk to a healthcare professional about whether a supplement is the right fit for your individual health, and about any potential drug interactions or safety concerns.

If your nails crack, break, or chip without an apparent reason, you may be dealing with brittle nails. Oftentimes, brittle nails are a normal sign of aging.

 Regular nail salon visits and frequent handwashing may also weaken nails.

“There are many causes of brittle nails, which include too much or too little moisture and chemical damage from nail polish, cleaning agents, or detergents,” says Rahaf Al Bochi, RDN, a Baltimore-based spokesperson for the Academy of Nutrition and Dietetics and the owner of Olive Tree Nutrition. “Most often, the cause of brittle nails is wetting and drying nails over and over, which removes moisture and causes them to be dry and brittle.”

That said, brittle nails could also be a sign of an underlying issue, such as a nutritional deficiency.

“If a diet lacks foods rich in these nutrients or if there is poor digestion or absorption of nutrients, then a deficiency may occur, and further lab testing would be needed to confirm,” says Al Bochi.

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Nutritional Deficiencies That Can Cause Brittle Nails

“Deficiencies in several vitamins or minerals can cause brittle nails,” says Al Bochi.

According to Al Bochi, a lack of one or more of these nutrients might make nails brittle:

It’s also important to get enough omega-3 fatty acids for healthy nails.

In addition to brittleness, nutritional deficiencies may cause the following nail changes:

For instance, a lack of folate can cause changes in fingernail pigmentation.

“Your healthcare provider can run lab testing to assess for deficiencies,” says Al Bochi.

Note that extreme eating habits may contribute to nutritional deficiencies, particularly disordered eating such as anorexia nervosa or fad diets, adds Jamie Rosen Manning, MD, a dermatologist based in New York City.

Can You Reverse Your Brittle Nails by Getting More Nutrients?

It depends.

If your doctor thinks that a nutritional deficiency could be the culprit, they might suggest switching up your diet. “Eat a variety of foods to get the vitamins and minerals your body needs to nourish your body from the inside out,” says Al Bochi.

For example, they might recommend the following foods to get more of these vitamins:

  • Iron Beef, poultry, fish, beans, and lentils

  • Vitamin C to Help With Iron Absorption Citrus fruits, kiwi, red peppers, strawberries, and tomatoes

  • Vitamin B12 and Biotin Beef liver, meats, poultry, fish, clams, oysters, eggs, cheese, milk, nuts, seeds, sweet potatoes, spinach, and broccoli

  • Zinc Oysters, meat, fish, poultry, beans, nuts, whole grains, and dairy

  • Protein Meat, fish, poultry, nuts, seeds, and legumes

  • Magnesium Nuts, seeds, avocados, spinach and other greens, and whole grains

  • Folate Spinach, black-eyed peas, and asparagus

  • Omega-3 Flaxseed, chia seeds, and salmon

Should I Take Supplements for Stronger Nails?

If a nutrient deficiency is truly the reason for your brittle nails, your doctor might suggest addressing your diet first, says Dr. Manning. But if your doctor gives you the green light to take a supplement as well, there is some research showing that certain kinds are beneficial for brittle nails.

Biotin supplements may help brittle nails because biotin is essential for the production of keratin, a protein that forms nails.

 One older study found that 63 percent of those with brittle nails who took a daily biotin supplement noticed improvements in their nails.

 And a more recent review of research suggested biotin supplementation (along with increasing intake of other micronutrients) could be helpful.

While some studies indicate that biotin supplements strengthen brittle nails, these studies are small and of lower quality. More research is needed to conclusively show a connection between biotin supplements and brittle nails.

Other research shows that supplementing with “bioactive collagen peptides” may help improve brittle nails, with 64 percent of study participants noticing improvements.

 Collagen is a protein that helps strengthen your skin, muscles, and bones.

“Collagen is made of amino acids that help form keratin, so it makes sense biologically,” says Cristina Del Toro Badessa, MD, a board-certified physician with Artisan, a plastic surgery practice in Atlanta. “I often suggest it as part of a holistic nail health plan, especially since it may also benefit skin and joint health. It’s not a guaranteed fix, but it’s safe, and many of my patients do report stronger nails after a few months.”

But it’s unclear if taking biotin supplements can truly make brittle nails stronger (particularly in the absence of a true deficiency).

If you want to take a supplement, talk to your doctor first.

“In my experience, it’s safe to try a moderate dose of biotin short-term, particularly if we’ve ruled out more serious causes like iron or thyroid issues,” says Dr. Del Toro Badessa. “I also remind patients to let their doctor know if they’re taking it, since high-dose biotin can interfere with lab tests, including thyroid and cardiac markers.”

If you think you could benefit from supplements, we're here to help. Check out our list of the best vitamins for hair, skin, and nails, as recommended by RDs.

Certain supplements may interact with any over-the-counter or prescription medications you may be taking, making them less effective or, in some cases, leading to unwanted effects.

And going over the recommended daily amount of certain supplements may cause side effects.

 For example, too much zinc can lead to nausea and vomiting, while excess amounts of iron might cause issues like constipation and stomach pain.

Even though biotin may improve nail strength, “supplementation with biotin can interfere with some lab test results, making them look falsely elevated or decreased,” says Manning. Two of the main tests affected by biotin include hormone tests and tests for heart attack markers, where false results could have dangerous consequences.

Vitamins and supplements are also not evaluated by the U.S. Food and Drug Administration (FDA). So if you do get the green light to take them, ask your doctor if there are any brands in particular they recommend, and follow up as directed.

Other Factors That May Cause Brittle Nails

Outside of nutritional deficiency, there are a number of other reasons why you might have brittle nails, says Al Bochi.

For example:

  • Dishwashing may dry out your nails, making them brittle, says Al Bochi. Wear cotton-lined rubber gloves when you do the dishes or when cleaning and using harsh chemicals.
  • Nail polish remover can wear down your nails, making them more brittle over time. Choose products that don’t contain acetone to prevent this.

     Certain lacquers and moisturizers can strengthen brittle nails.

  • Brittle nails may be a sign of a fungal infection or an underlying health issue such as psoriasis, a thyroid disorder, or Raynaud’s syndrome (where you have less blood flow to your nail beds).

  • Brittle nails may be a side effect of a medical treatment like chemotherapy.

  • Even the climate you live in can make a difference. “Hot, dry climates, or even cold, dry air indoors, can draw moisture out of the nails, making them more brittle,” says Del Toro Badessa, adding that nails contain water, and when moisture drops, they lose flexibility and are more prone to splitting or cracking.

“I tell patients to treat their nails like they treat their skin: Nourish them from the inside, protect them from the outside,” says Del Toro Badessa.

The Takeaway

  • Brittle nails that chip easily are usually a sign of aging, external damage, or certain medical treatments.
  • In rare cases, brittle nails could be a sign of a nutritional deficiency.
  • Lack of iron, B vitamins like biotin or B12, zinc, protein, or magnesium in your diet may contribute to brittle nails.
  • Healthy, well-rounded meals will strengthen your nails. If you still have a nutritional deficiency, your doctor may recommend dietary supplements.
EDITORIAL SOURCES
Everyday Health follows strict sourcing guidelines to ensure the accuracy of its content, outlined in our editorial policy. We use only trustworthy sources, including peer-reviewed studies, board-certified medical experts, patients with lived experience, and information from top institutions.
Resources
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Jacquelyn-Dosal-bio

Jacquelyn Dosal, MD

Medical Reviewer

Jacquelyn Dosal, MD, is a board-certified dermatologist at Skin Associates of South Florida in Coral Gables. She practices general, medical, cosmetic, and surgical dermatology.

Dr. Dosal provides compassionate care to all her patients, listening to their concerns and creating a treatment plan with each patient's priorities and real life in mind.

She is a member of the voluntary faculty at the University of Miami.

Leslie Barrie

Author
Leslie Barrie is a health and nutrition writer and editor who loves running marathons and attempting to cook healthy meals for her family (even if they don’t always turn out as planned). She received her bachelor of science degree at UCLA and her master of science degree at the Columbia University Graduate School of Journalism. She has written and edited for publications like Health magazine, Seventeen, and Woman’s Day. Leslie won a Hearst Spotlight Award for her work in 2018 at Woman’s Day, and helped plan the Woman’s Day Red Dress Awards, an event honoring changemakers fighting to end heart disease in women.

When she isn’t writing, Leslie loves chasing her daughter and son around outside, going on family hikes, and starting her day with a big bowl of muesli.