Scurvy disorders, unusual eating habits, alcoholism, and old people who live alone. Other risk factors include intestinal malabsorption and dialysis. Humans and certain other animals require vitamin C in their diets to make the building blocks for collagen. Diagnosis typically is based on physical signs, X-rays, and improvement after treatment. Treatment is with vitamin C supplements taken by mouth. Improvement often begins in a few days with complete recovery in a few weeks. Sources of vitamin C in the diet include citrus fruit and a number of vegetables such as tomatoes and potatoes. Cooking often decreases vitamin C in foods. Scurvy
Vitamin B12 deficiency be considered only if blood testing is inconclusive. The Schilling test was a radio-isotope method, now outdated, of testing for low vitamin B. The National Institutes of Health (NIH) has found that "Large amounts of folic acid can mask the damaging effects of vitamin B deficiency by correcting the megaloblastic anemia caused by vitamin B deficiency without correcting the neurological damage that also occurs", there are also indications that "high serum folate levels might not only mask vitamin B deficiency, but could also exacerbate the anemia and worsen the cognitive symptoms associated with vitamin B deficiency". Due to the fact