RELATED: If You See This on Your Nails, It Could Be a Tell-Tale Sign of Diabetes. One common medical cause of breakage-prone nails is iron deficiency anemia. This may occur if there is a lack of iron in someone’s diet, an inability to absorb iron, blood loss, or even pregnancy. “Iron helps the hemoglobin in your red blood cells carry oxygen,” says Dimitar Marinov, MD, Ph.D., a nutritionist who specializes in nutrition and dietetics. “As you develop iron deficiency, the capacity of your red blood cells to carry oxygen is reduced, which leads to reduced oxygen delivery to the nails and the development of brittle and curved nails.” There are a few nail-related symptoms to look out for if you think you may have iron deficiency anemia. The first is dry, brittle nails that appear split or have vertical ridges, says Nelya Lobkova, DPM, a board-certified podiatrist in New York City. Another is a condition called koilonychia—or “spoon nails”—which can cause nails to become flat or concave. Some koilonychia patients note that their concave nails could even hold a droplet of water. If either of those symptoms sounds familiar, look out for the other signs of iron deficiency anemia. These include shortness of breath, pale skin, muscle weakness, heart arrhythmias, dizziness, and cold hands and feet, says Marinov. There are a few vitamin B deficiencies that can lead to brittle nails, but the most common is related to vitamin B12. Vitamin B12 deficiency can also lead to anemia, causing brittleness for the same reason as iron deficiency anemia: reduced oxygen levels in the nails. Advanced vitamin B12 deficiency can also lead to a condition called melanonychia. This is when the nails become blue or black with wavy, longitudinal dark streaks and brownish pigmentation, says Marinov. Other symptoms of vitamin B12 deficiency include anemia, inflammation of the tongue, shortness of breath, pale skin, muscle weakness, heart arrhythmias, dizziness, and cold hands and feet, says Marinov. Fortunately, iron and vitamin B12 deficiencies are not permanent, and can often be fixed with a few updates to your diet. According to Healthline, if you have iron-deficiency anemia, you’ll want to increase your consumption of iron-rich foods, such as meat, fish, poultry, beans, and lentils. Vitamin C-rich foods—such as citrus and cruciferous vegetables—can help your body absorb that iron and use it more easily. If you have a vitamin B12 deficiency, you’ll want to eat more foods that contain the nutrient to restore your body’s levels. According to WebMD, these include beef, liver, chicken, fish, shellfish, and eggs. With both iron deficiency and vitamin B12 deficiency, your doctor may prescribe additional supplements to help your body get the nutrition it requires. RELATED: For more health advice delivered straight to your inbox, sign up for our daily newsletter. If you’re concerned about your nails—or think you may have a nutrient deficiency for any other reason—it’s important to visit your doctor immediately. A medical professional will be able to assess them, consider your personal health history, and run the appropriate tests needed to get a complete picture of the situation. From there, they’ll be able to diagnose any nutritional deficiencies—or conditions that could mimic them—and prescribe the appropriate supplements or dietary recommendations.ae0fcc31ae342fd3a1346ebb1f342fcb RELATED: If You Notice This With Your Fingernails, Get Your Thyroid Checked.