Eat Smart · General Health · Nutrition

All About Vitamin D

This year, many SU students took advantage of Thanksgiving break and visited their doctors and healthcare professionals at home. Medical offices were packed with students desperate for their last minute flu shots and physicals before the bone-chilling Syracuse winter. Yet, did anyone think to get a blood test? Especially on a campus where sunshine is limited, students should pay close attention to the amount of vitamin D, also known as the “sunshine vitamin,” produced in their bodies. A simple blood test can show if an individual is getting enough vitamin D from sunlight exposure or dietary sources such as liver, fatty fish like salmon and sardines, cod-liver oil, egg yolks, and fortified milk. Though a worldwide problem with long-term health consequences, vitamin D deficiency is prevalent amongst three quarters of teens and adults in the U.S alone.

Small amounts and sometimes inaccessible sources of vitamin D pose an even greater concern and demand for its consumption. Vitamin D maintains levels of calcium and phosphorus in the blood that favor bone mineralization. When blood calcium levels dip, the parathyroid gland releases parathyroid hormone, which stimulates enzymes in the kidney to convert 25-hydroxyl vitamin D3 in the liver to the active form of vitamin D. Active vitamin D enters the blood and travels to the intestines, bones, and kidneys, where it acts to increase calcium levels in the blood. In addition to these three major target tissues, vitamin D receptor proteins have been found in the nuclei of many other cells, including those of the colon, pancreas, skin, breast, and immune system. Within these areas of the body, vitamin D acts to prevent cells from becoming cancerous, protecting against autoimmune disorders like type 1 diabetes and multiple sclerosis, and other disease processes such as cardiovascular disease and type 2 diabetes. The more the world understands the importance of vitamin D, the more it will know about deficiency.

When vitamin D is deficient, only about 10 to 15 percent of the calcium in the diet can be absorbed. In other words, not enough vitamin D can result in the lack of proper bone mineralization and abnormalities in bone structure. Osteomalacia, a disease characterized by bone pain, muscle aches, and an increase in bone fractures, occurs in vitamin D deficient adults when there is an insufficient amount of calcium available to form the mineral deposits needed to maintain their health. For adolescents and adults at risk for this disease, different actions are recommended from person to person. For instance, vitamin D supplements are recommended for children and adolescents who do not get regular sunlight exposure and do not ingest at least four cups of vitamin D-fortified milk per day. Other groups that might benefit from supplements include people who do not drink milk or consume dairy products, individuals with dark skin pigmentation, and individuals who do not absorb fat normally. Keep in mind that it is important to take supplement dosages seriously to prevent toxicity; the recommended dietary allowance for college-aged students is set at 600 IU.

Are you nervous about your levels of vitamin D? Don’t be. Although sources seem limited, there are plenty of options to obtain the recommended daily amount of vitamin D if enough attention is paid to diet and outdoor activity, as well as guidance from a healthcare professional. Even in Syracuse, vitamin D absorption is attainable; awareness of deficiency is what is key.

By Allison Milch