7 Common Signs of Vitamin Deficiencies in Nails

Your fingernails can provide visible clues about nutritional status and overall health. Unusual changes in nail texture, color, or growth rate may indicate dietary gaps or other underlying conditions.

Discover seven ways your nails may signal nutritional deficiencies, and discover simple but effective natural strategies to support nail health.

7 signs of nutritional deficiencies in nails

Approximately 80 percent of fingernails and toenails are made of keratin. This structural protein helps provide strength and protection to various parts of the body, including your hair, skin, and nails. 

In addition to keratin, nails also contain lipids, minerals, and, surprisingly, a significant amount of water.

Research published in the Indian Journal of Dermatology, Venerology, and Leprology notes that the nail plate depends on a precise nutrient balance. As a result, even minor deficiencies can lead to noticeable changes in nail structure and may also affect the nail bed.

Healthy nails usually appear smooth, uniformly colored, and relatively firm. Changes in nail texture, color, growth, or strength can reflect shifts in nutrient levels, circulation, digestion, or overall metabolic health.

Here are seven common nail changes and what they may suggest about your nutritional status.

1. Vertical ridges

Pronounced ridges running from the nail bed to the tip of the nail are commonly associated with aging and dehydration. They may also be linked to deficiencies in iron, biotin, zinc, or vitamin B12, all of which support normal nail formation and growth.

Prioritize pasture-raised meats and wild-caught seafood, which offer highly bioavailable protein, iron, and B vitamins, including biotin, a vital nutrient for keratin synthesis. Shellfish, especially oysters, are rich sources of zinc.

Diets high in refined carbohydrates can promote nutrient deficiencies, dehydration, microbial imbalances, and oxidative stress, all of which may contribute to nail irregularities.

This explains why adopting a nutrient-dense, low-carbohydrate diet, such as Healthy Keto®, can further support nail health by promoting metabolic health, fluid balance, and optimal nutrient levels over time.

Watch the video below to learn how your nails can help identify potential deficiencies.

2. Horizontal ridges

Horizontal ridges or grooves, also called Beau’s lines, often form when nail growth is temporarily slowed by systemic stressors.

Common triggers include severe illness, certain medications, surgery, injury, or malnutrition. In particular, these lines may be linked to low protein, iron, zinc, calcium, or vitamin C.

Ensure adequate intake of high-quality protein and minerals from foods such as oysters, sprouted pumpkin seeds, and pasture-raised meat and dairy to promote consistent nail growth and help reduce the risk of recurring horizontal ridges.

Raw sauerkraut is a rich source of vitamin C, which is a vital cofactor for collagen synthesis. Collagen helps provide the structural foundation for the nail bed, as well as the amino acids necessary for building strong keratin.

3. Brittle or splitting nails

Brittle or splitting nails can be indicative of dehydration, aging, and general malnutrition, especially deficiencies in B vitamins, iron, calcium, and magnesium. 

Animal-based foods naturally provide many of the nutrients needed for healthy nails. Some of the best sources include pasture-raised eggs, beef liver, and wild-caught fatty fish, as they provide some of the most absorbable forms of protein, iron, and B vitamins.

For added support, include pumpkin seeds, leafy green vegetables, and avocados to promote magnesium, zinc, and folate, all of which help strengthen the nail plate.

4. Spoon-shaped nails 

Spoon-shaped nails, also referred to as spoon nails or koilonychia, appear inverted, with the nail curving upward at the edges to create a scooped shape.

This pattern is commonly associated with iron deficiency anemia and chronically low iron stores. 

Iron supports the production of healthy red blood cells and facilitates oxygen delivery to tissues, including the nails. When iron is low, the nail bed may not receive enough oxygen, and nails may become thinner, softer, and lose their normal curvature in both fingers and toes.

Prioritize iron-rich whole foods, especially animal-based sources. Animal products provide heme iron, which is significantly more bioavailable than the non-heme iron in plant foods. When eating plant iron sources, pair them with vitamin C-rich foods to support absorption.

“Supporting digestive health is also essential, as iron status depends not only on intake, but also on absorption,” explains Dr. Berg. “In many cases, low iron is linked to low stomach acid.”

Low stomach acid is often linked to the aging process, acid-blocking medications, microbial imbalances, and high-carbohydrate diets.

Consuming a teaspoon of diluted apple cider vinegar in eight ounces of water, either with or before a meal, may help create a more acidic stomach environment, which is crucial for mineral absorption.

Fermented foods containing live probiotic cultures, such as kefir and raw pickled vegetables, can further support a healthy microbiome, balanced digestive fluids, and the absorption and production of nail-supportive nutrients.

5. Nail clubbing

Nail clubbing is a change in which the fingertips enlarge, and nails curve tightly around the tips, rather than forming a gentle, straight slope from the cuticle to the fingertip.

Clubbing often reflects chronically low blood oxygen or long-term circulatory stress and is commonly associated with conditions affecting the lungs, heart, or liver.

While nail clubbing should always be evaluated by a healthcare provider, as it may be linked to systemic disease, lifestyle and diet can help support healthy oxygenation and circulation.

Helpful strategies include regular physical activity, avoiding smoking and secondhand smoke, and adopting a nutrient-dense diet rich in nutrients that support oxygen delivery, such as iron, copper, B vitamins, vitamin C, and essential fatty acids.

In addition to addressing any potential micronutrient deficiency, it’s also recommended to avoid the use of nail polish and limit exposure to harsh chemicals, which can further weaken nails and interfere with normal nail growth and appearance.

6. White spots on nails 

Small white spots, specks, or nail discoloration, known as leukonychia or nail pitting, most often result from minor trauma to the nail matrix, which is the area at the base of the nail where new nail cells form.

They may also follow periods of high metabolic or physiological stress, allergic reactions, or recent illness, signaling that immune activity may have increased the body’s nutrient needs.

When white markings appear as transverse lines across multiple nails, they may indicate short-term nutritional imbalances, such as deficiencies in zinc, calcium, or B vitamins. More extensive white banding can be associated with low blood protein levels.

Include foods such as oysters and pasture-raised beef to provide bioavailable protein, zinc, and B vitamins that support nail growth and immune function.

Support mineral balance by getting regular sun exposure for vitamin D, which helps regulate calcium metabolism. In addition, focus on foods rich in vitamin K2, including egg yolks, butter, dairy, organ meats, oily fish, and fermented foods, to help direct calcium to appropriate tissues.

To further support optimal health and nutrient utilization, limit refined carbohydrates, ultra-processed foods, and industrial seed oils, and emphasize minimally processed, nutrient-dense foods to promote nail growth.

7. Nail color changes 

While nail discoloration can result from injury or aging, persistent changes in color may be linked to underlying nutritional deficiencies and poor dietary patterns.

Yellowing of the nails is often associated with fungal infections, which can be influenced by immune activity, diet, and lifestyle. Yellow discoloration may also occur alongside low vitamin E levels or as a result of metabolic issues.

Nail hyperpigmentation, which usually presents as darkened nails or brown to bluish-black streaks, is often associated with vitamin B12 deficiency or inadequate protein intake.

Significant whitening of the nails has been linked to low selenium intake and zinc deficiency and is commonly seen in older adults or those with low stomach acid. 

To support healthy nails, prioritize shellfish, liver, salmon, tuna, pasture-raised beef, eggs, and dairy, which offer highly bioavailable protein, minerals, and B vitamins, including B12 and biotin.

Brazil nuts are one of the most concentrated food sources of selenium, which supports keratin formation. Other good sources include seafood, turkey, and chicken.

FAQ

Source