We were starting to think that Vitamin D deficiency was a thing of the past. I mean, when was the last time you met someone with rickets? But a recent study in Pediatrics showed that over six million children in the United States do not get enough Vitamin D. That is one out of every five kids! It seems that Vitamin D deficiency is more common than we thought.
Vitamin D is an important vitamin! New studies are proving that vitamin D can help prevent many diseases such as cancer, depression, diabetes, hypertension, osteoporosis, chronic fatigue, autoimmune diseases and cardiovascular disease. Other research has linked low Vitamin D levels to obesity; studies show that overweight individuals are much more likely to be Vitamin D deficient. It is not clear, however, whether increased body fat leads to Vitamin D deficiency or if low Vitamin D levels cause a person to gain weight. Is one responsible for the other? More research is needed in this area.
There are a few different ways to get vitamin D. Vitamin D may come from foods or vitamin supplements; vitamin D can also be made by the skin when it is exposed to ultraviolet rays (UV light). Fortified foods are the main dietary sources of Vitamin D as few foods naturally contain it. Although milk is fortified with vitamin D, dairy products made from milk, such as cheese and ice creams, are generally not fortified with vitamin D. Fatty fish and fish oils are natural sources of Vitamin D.
Vitamin D deficiency is often missed because there are no real symptoms associated with it. Rickets and osteomalacia (softening of the bones) are the most common signs of vitamin D deficiency but there is no way for parents to tell if their child is suffering from these illnesses. The only way to prove that your child is vitamin D deficient is by completing a blood test which screens for a particular form of vitamin D, called 25-hydroxyvitamin D (25(OH)D).
Think that name sounds complicated? Unfortunately, many doctors do too. In fact, doctors often order the wrong blood test when assessing vitamin D levels. Be sure to ask for 25(OH) D blood test not 1, 25-dihydroxy-vitamin D (aka calcitriol). With such complicated names, it is no wonder that such mistakes are made!
Vitamin D deficiency exists when 25(OH) D levels fall below 25 ng/mL. Levels may vary depending on time of year, direct sunlight exposure, skin color and vitamin D consumption. Levels should be between 50 – 80 ng/mL year-round for both children and adults.
As a doctor, I am finding more and more children with low levels of vitamin D, mainly because kids are spending less time in the sun. These days, toddlers are more often inside watching TV than playing outside. And if they are in the sun, they are lathered with sun block, which reflects the sun’s rays and decreases vitamin D formation. Obviously, sunscreen is important and should not be avoided! But it does lead to lower levels of vitamin D. Also, many toddlers do not get enough vitamin D to meet their needs since there are limited food sources of high vitamin D content.
The current recommendation is 400 IU per day in the form on of vitamin D3 (cholecalciferol). New studies are showing that higher levels may be needed to prevent the diseases discussed above. Many are now recommending 1,000 IU per day in the form of vitamin D3 (cholecalciferol). If your child doesn’t get this amount of vitamin D in his diet, you may want to consider a multivitamin that contains vitamin D.