In individuals with IBS and low levels of vitamin D supplementation is recommended. Osteomalacia is a disease in adults that results from vitamin D deficiency. Several forms (vitamers) of vitamin D exist. Hypervitaminosis D is a state of vitamin D toxicity. In those with vitamin D toxicity, steroids may be useful. Light skin pigmentation protects against vitamin D deficiency. It is caused by supplementing with high doses of vitamin D rather than sunlight. Periodic measurement of serum calcium in individuals receiving large doses of vitamin D is recommended. Sunscreen can also reduce vitamin D production. Production of vitamin D is essential for human health. Additionally calcium and vitamin D supplementations may be used. Its other functions are insulation, temperature regulation, sensation, and the production of vitamin D folates. This leads to increased metabolism of vitamin D, thus decreased vitamin D levels. The link between vitamin D intake and kidney stones is also tenuous. A single trial of vitamin D did not find benefit.