Certain nutritional deficiencies can contribute to the development of canker sores, but a deficiency in vitamin D is not usually one of them. For the most part, vitamin D helps with calcium absorption. Deficiencies in this vitamin can lead to low serum calcium and phosphate levels, which increase the risk of rickets, osteomalacia and osteoporosis. A vitamin D deficiency does not, however, cause canker sores. Increasing your intake of vitamin D will neither prevent them from forming nor aid in their recovery.

Canker Sores

Canker sores are small lesions that develop along the lining of your mouth and gums. While their exact cause is unclear, certain factors can contribute to an outbreak. Aside from injury, food sensitivities and allergic response, some people develop canker sores -- or aphthous ulcers -- from diets lacking sufficient vitamin B-12, zinc, iron or folic acid, another name for vitamin B-9.

Self-Care

Most canker sores respond favorably to self-care measures. Rinsing your mouth with salt water, baking soda or diluted hydrogen peroxide can help ease discomfort and speed recovery. Numbing agents and anti-microbial mouthwashes can also provide relief, the American Dental Association notes. At the same time, avoid foods that are known to aggravate the sores, such as spicy or acidic fare.

Medical

If your canker sores don’t improve with self-care or are fairly large, medical treatment is often necessary. To start, your doctor will likely prescribe a mouthwash to reduce inflammation and alleviate associated pain. He may also suggest a topical paste to apply over the ulcer to aid in healing and minimize discomfort. If he suspects that a nutritional deficiency is contributing to your condition, he may prescribe a nutritional supplement of vitamin B-6, vitamin B-12, folic acid and zinc as well.

Prevention

Preventing canker sores often entails reducing your exposure to their triggers. Lack of vitamin D isn’t one of them. Avoiding any food that you’re sensitive to, such as nuts, cheese, strawberries, eggs or chocolate, can minimize the occurrence of canker sores. You should also eat plenty of fruits, vegetables and whole grains to avoid nutritional deficiencies that may lead to an outbreak. In fact, eating yogurt regularly can introduce cultures that prevent these ulcers.