To find the best vitamins for nails, you need a more comprehensive look at your overall health, especially to check for vitamin deficiencies. “Deficiencies in vitamins like iron, zinc, biotin, and vitamin B, as well as low levels of iron, can all show up on your nails,” says Dr. Nussbaum. A look at the ingredients you should consider, below.

Biotin

Perhaps the most popular ingredient known for its hair and nail health support, biotin, aka vitamin B7 is a water-soluble B vitamin that helps convert nutrients into energy in the body. “It supports keratin production, a key structural protein in nails,” says Fazio. “Low levels of biotin, while rare, are linked to brittle nails.” While biotin supplements are generally considered safe, it’s important to know that they can affect the results of blood tests, especially lab testing for thyroid issues. “While many nail experts used to recommend biotin for brittle nails, there has been a re-analysis of a lot of the data and we are now questioning the efficacy of this vitamin B coenzyme for nail health,” says Dr. Stern. The FDA issued a warning in 2017 that excessively high biotin consumption can cause incorrect lab results.

Protein

Protein is essential for overall nail health. “Nails are largely composed of protein and so if you are consuming adequate protein it is highly unlikely that a specific diet will benefit your nails,” says Dr. Stern. To boost nails, Dr. Stern recommends generally focusing on protein intake because “keratin, which is what your nails are composed of, is protein-derived.”

Collagen

“Collagen is a protein that gives shape and strength to tissues,” says Dr. Nussbaum. “It’s a building block of nails, hair, and teeth.” Fazio recommends hydrolyzed collagen peptides (types I and III) as the most effective form for supplementation. “Your body needs a full range of amino acids to build nails, and collagen works best when your overall protein intake is sufficient.”

Vitamin C

Vitamin C is a water-soluble antioxidant that protects cells from oxidative stress and damage. “It’s essential for collagen synthesis, which helps maintain skin elasticity, hair structure, and nail strength,” says Fazio. “It also helps with iron absorption.”

Zinc

An essential micronutrient and trace mineral, zinc is “used in over 300 metalloenzymatic reactions and over 2,000 transcription factors that are needed for regulation of lipid, protein, and nucleic acid metabolism and gene transcription,” says Dr. Stern. That means it’s key for cell repair, growth, and inflammation control. “Inadequate zinc intake can cause degeneration of the nail plate or something called “Beau’s lines” which are horizontal grooves across the nail,” says Dr. Nussbaum.

Iron

Iron is an essential mineral. “It supports red blood cell production and oxygen delivery to tissues, including nails,” says Fazio. “Iron deficiency is a common cause of hair shedding, dull skin, and pale, or discolored nails.” Iron deficiency or anemia is common, and your nails could be a sign. “Iron deficiency may contribute to vertical ridges, brittle, or spoon-shaped nails,” adds Dr. Nussbaum.