She didn't always order the test. For more than two decades in private practice, in fact, Dr. Patricia Czapp almost never checked the vitamin D levels of her patients.
Things have certainly changed.
"For the last two years, I've been testing virtually all of my patients," said Czapp, a family doctor at Annapolis Primary Care. "The vast majority are straight-out deficient or insufficient. It's frightening to think there's that many people walking around with that deficiency."
What doctors are beginning to understand is that vitamin D isn't just important for absorbing calcium and building bones. And new research seems to be coming out by the day suggesting vitamin D deficiency can lead not just to osteoporosis but possibly to heart disease, multiple sclerosis, diabetes, even cancer. Vitamin D is believed to impact the immune system and, one researcher suggests, perhaps even the functioning of the brain.
"When you start reading about vitamin D, how can you not offer that to your patients?" said Czapp, who was persuaded by a newly trained colleague to check for deficiencies. "What we're coming to find out is most of the cells in the body have a vitamin D receptor. Vitamin D touches hundreds of different genes in the body, regulating the immune system, fighting infection, cancer cells."
She isn't the only physician ordering more vitamin D tests. She is part of a growing trend among doctors turning the once-rare test into a routine part of the annual physical, making it one of the top five blood tests ordered nationwide, according to two leading lab companies.
Patients, reading recent headlines about vitamin D or hearing about it on the news, are also pushing the popularity of the test, asking their doctors about a vitamin they rarely thought about before. One grass-roots health organization is advocating that everyone have their vitamin D levels checked.
All this comes as the American Academy of Pediatrics doubled its recommendation last month of how much vitamin D children should take daily and as other groups are pushing for adults to get up to 10 times more than is currently recommended in their diets.
As many as half of Americans, middle-age and older, are believed to get an inadequate amount of vitamin D.
"That's quite sobering and it really says we've got to do better with vitamin D nutrition," said Dr. Anthony W. Norman, a biochemist at the University of California, Riverside who has studied vitamin D for decades.
