Many people know that vitamin D is necessary for building of strong bones, but that is not the only reason it is so important. It is a critical human need for optimizing many body systems.
“Vitamin D is so important to the body because it influences the functioning of more than 200 genes. Thus, it is vital for many systems not just the well-known bone building,” said Boyd Hoddinott, M.D., a family physician in Bellefontaine, Ohio.
Your body needs calcium to build strong bones and teeth in childhood and adolescence. As an adult, you need vitamin D and calcium to maintain bone mass. This helps prevent osteoporosis. Vitamin D also helps your body keep the right amount of calcium and phosphorus in your blood.
The amount of vitamin D your body needs can vary depending on your weight, your genetic makeup, your skin color, whether you have any chronic conditions, and even where you live.
Many people do not get enough vitamin D in their diets. Adults who do not get enough vitamin D are at risk for osteomalacia (muscle weakness and weak bones) and osteoporosis (thin bones). Children who do not get enough vitamin D are at risk for rickets.
“Until further studies are done, I think 800 IU daily is enough for children and teenagers,” explained Hoddinott.
“It has been known for a century that very low vitamin D caused the bone disease rickets. More recently, we have learned that all the calcium and drugs in the world will not prevent or adequately treat osteoporosis unless you have adequate vitamin D on board,” Hoddinott said. “And, now we are beginning to understand the importance of ‘D’ in muscle function and in preventing diseases other than rickets including; autoimmune, infectious, bone, muscle and cardiovascular diseases, and cancer.”
Foods that naturally contain vitamin D include fish, eggs, cheese, and butter. There are also vitamin D-fortified foods, such as milk and milk alternatives, orange juice, and breakfast cereals. Vitamin D supplements are also available over the counter and by prescription.
“In five years of testing patients, I have never seen vitamin D toxicity. Clearly, everyone should take vitamin D supplements. It is probably not possible to get enough vitamin D in your diet without supplementing, no matter how much oily seafood you eat,” said Hoddinott. “A glass of milk only has about 90 IU, which would be inadequate for a daily intake amount.”
It is important to talk to your family physician if you think that you may not be getting enough vitamin D. They will ask you about your diet and your exposure to sunlight, as well as any other risk factors that you may have. Your family physician may also suggest testing your vitamin D level to help you decide if a supplement is needed.
According to Hoddinott, vitamin D deficiency is one of the most important public health issues. It is an important issue and should be monitored in patients. So, remember to talk to your family physician about getting an adequate amount of vitamin D.
Adults need at least the following amounts of vitamin D:
• Under age 70: 600 IU daily
• Over age 70: 800 IU daily
• Children and adults who do not get any sun exposure may need 800 to 1,000 IU daily.
• For children from birth to age 18, the recommended daily dose is 400 IU.
• If you breastfeed your baby, your physician will prescribe a vitamin supplement that has vitamin D (because human milk only has a small amount of vitamin D). Talk to your physician before giving older children vitamin supplements.
Those who are at risk for vitamin D deficiency include older adults, breast-fed infants, people who are obese
• People with darker skin
• People with limited exposure to sunlight
• People who live in the northern United States