Split fingernails are usually caused by environmental hazards, such as prolonged exposure to water or trauma, according to the Better Health Channel. Though not often a primary cause, a vitamin deficiency may also be to blame. If you suffer from splitting nails, it is possible you might be missing some crucial nutrients.
If your nails are dry, brittle and cracking, biotin could provide a much-needed boost. Biotin is a B vitamin, synonymous with vitamin B-5. It is available as a dietary supplement, but is also available through many foods. The National Institutes of Health states that biotin is available in legumes, vegetables from the cabbage family and dairy, fish, whole grain cereals and lean beef. The recommended amount of biotin -- 30 micrograms per day -- should be available to you if you eat a balanced diet, according to the National Institutes of Health.
Vitamin B-12 helps your body break down fatty acids and assists your body in keeping red blood cells and nerve cells healthy, according to the National Institutes of Health Office of Dietary Supplements. It's found in meats, fish and shellfish. While taking vitamin B-12 won't make your nails stronger overnight, a lack of it can cause fingernails to dry out, discolor and become brittle. The recommended dose for adults is 2.4 micrograms of vitamin B-12 per day, suggested by the NIH ODS. If your fingernails are splitting from a vitamin B-12 deficiency, it's ideal to speak to a health care professional. When healthy, the human body stores a few years worth of the vitamin at a time. If you're deficient or unable to process the vitamin, other serious health factors may be at work.
Vitamin C plays a part in making collagen, the protein responsible for skin. Collagen is also present in the cuticles around your nails. A lack of vitamin C may lead to hang nails. A serious deficiency can cause nails to dry out and become brittle. Brittle nails are more prone to cracking and splitting than healthy nails. Unless otherwise directed by a health care professional, 75 milligrams of vitamin C per day is necessary for adults. The human body doesn't make vitamin C on it's own, cautions the National Institutes of Health, so it is important to get the proper amount from diet or a nutritional supplement. Green, leafy vegetables, citrus fruits, berries and peppers are excellent sources of vitamin C, as outlined by the National Institutes of Health.