Top Nutrition Tips for Healthy Fingernails

Our finger and toenails are made from keratin, a protein that also forms human hair, the outermost layer of the skin, and in animals, horns, wool, and feathers.

Healthy fingernails are smooth, without horizontal ridges, pits, or grooves, and they have the same texture all over. Healthy nails are uniform in color, without discolored spots or stripes. If a nail is damaged, any discoloration should disappear when the nail grows out. Vertical ridges—from cuticle to tip—are fairly common, especially as we age, and are not a cause for concern.

Fingernails are more than just a beauty concern; they can tell us a lot about our general physical health. Unhealthy nails are often a sign of a nutrient deficiency that could be corrected by diet or supplementation. In some cases, however, unhealthy nails indicate an underlying condition that requires medical intervention.

Symptoms that should be checked by a doctor include discoloration, clubbing (enlarged fingertips with curved nails), and Beau’s lines, which are horizontal ridges or indentations.

Biotin is a naturally-occurring B vitamin that supports metabolism and cell function. A deficiency can lead to brittle nails, hair loss, and skin rash. Biotin deficiency is rare, and most people get enough from their diet.

The vitamin supplement is often marketed as a miracle cure for hair and nail health. However, there is very little evidence that shows a significant advantage to supplementation in people without a deficiency. Instead, it’s best to focus on ensuring you're getting enough biotin from food sources, which include eggs, fish, and organ meats, such as liver.

All B vitamins are important for maintaining healthy skin, hair, and nails. Vitamin B12 helps the body form red blood cells and absorb iron, which is important for nail health. Good sources of B12 include poultry, meat, fish, and dairy. As most sources of B12 are animal proteins, people following a vegetarian or vegan diet may require a supplement to get enough.

Vitamin B9, also known as folate, is important for cell and tissue growth. A lack of folate may cause nail ridges, as well as other symptoms including fatigue, weakness, irritability, and poor concentration. Good sources of vitamin B9 include whole grains, beans, and green vegetables like spinach, asparagus, and Brussels sprouts.

Iron plays a major role in forming the red blood cells that distribute oxygen around the body, as well as aiding in the production and function of certain types of cells and hormones. Insufficient iron may lead to iron-deficiency anemia, which can cause fatigue, light-headedness, hair loss, and brittle nails. Iron deficiency is the most common nutritional deficiency worldwide, affecting 10 million people in the United States alone.

For most people, a balanced diet should provide sufficient iron, but in some cases, an iron supplement may be helpful. Groups at risk from iron deficiency include pregnant or menstruating women, people following a vegetarian or vegan diet, children, and the elderly. Dietary sources of iron include meat, poultry, seafood, lentils, and beans.

Zinc is vital for the normal functioning of the body. It supports wound healing, protein creation, and cell division. Because our nails are always growing due to cell division, zinc is important for healthy nails. It also boosts collagen production.

The body has no storage system for zinc, so it's important to ensure we're getting enough through our diets every day. Good sources of zinc include shellfish, poultry, whole grains, and legumes.

Evidence suggests that collagen has an important role to play in nail health. One study found that supplementation with specific collagen peptides can reduce brittle nails and improve nail growth. Collagen peptides are an easily digestible form of collagen that is available as supplements, but it is also possible to get this nutrient from food.

Collagen-rich foods include gelatin and cuts of meat that contain connective tissue, like brisket. Foods that contain collagen-boosting amino acids include fish, poultry, meat, eggs, dairy, legumes, and soy.

Although bones and nails are made from different substances, there's some indication that healthy bones are linked to healthy nails. Magnesium is an essential nutrient, supporting the function of the heart and nervous system and contributing to bone and muscle health.

For this reason, getting enough magnesium may help achieve and maintain healthy nails. Good sources of magnesium include dark green leafy vegetables, legumes, nuts, fish, poultry, and beef.

The cuticle is a thin layer of skin at the base of the nail that contributes to nail health by protecting new nail growth from bacteria. Omega-3 helps maintain the skin's moisture barrier and prevents inflammation, so may help promote healthy cuticles and in turn, healthy nails.

Omega-3 is easy to get from a balanced diet. Good sources include oily fish, nuts and seeds, and plant oils such as flaxseed and soybean.

Protein makes up the building blocks of the body and can be found in our bones, muscles, skin, hair, and nails. Keratin—the substance nails are made of— is a kind of protein, so ensuring adequate protein intake can help promote nail health.

Sources of protein include meat, fish, poultry and eggs. A vegan diet is typically lower in protein, but some good sources include tofu, pulses, and beans.