When you’re not ingesting enough vitamin D with your food, supplements can help
By Deborah Jeanne Sergeant
In addition to your summertime tan, your vitamin D stores have long since disappeared. While excessive sun is not so good for your skin, in moderation, it makes the body generate vitamin D, a pre-hormone that modulates many important bodily systems.
Why is vitamin D important?
With insufficient vitamin D, people are less able to absorb other nutrients.
“As many as 30% to 40% of those with hip fractures are vitamin D insufficient,” said Erica Smolinski, registered and certified dietitian nutritionist with Buffalo Nutrition & Dietetics, PLLC in Orchard Park. “Vitamin D helps the body absorb calcium and regulates both calcium and phosphorous levels in the blood. It plays an important role in bone growth and maintenance, influences cell growth and development and is required for proper immune function.”
She added that research shows the current recommended daily allowance could be lower than optimal for skeletal health.
Research about vitamin D continues to reveal more of its functions.
“Vitamin D works in every part of the body,” said Mary Jo Parker, registered dietitian in private practice in Williamsville. “It’s a prohormone that acts like a hormone. It does have vitamin properties but acts like a hormone in the body. They’re finding it’s beneficial in prevention and even treatments of so many conditions and diseases.”
Who needs more vitamin D?
Nearly everyone in North America. The sun is not intense enough from about October through May to trigger production of vitamin D. Parker said that older adults are not as good as synthesizing sunlight for vitamin D and that people of any age with darker skin tones are not as good as absorbing sunlight.
How much D do we need?
As a fat-soluble nutrient, vitamin D is stored by the body if it gets too much.
“The best way to know if you have enough is a blood test,” Parker said. “They’re pretty run of the mill. They’re not part of a typical metabolic panel. I routinely have my patients request to have that checked. Then we know what you’re doing, where you are on the range and if we need to supplement and how much.”
Vitamin D generated through sunlight exposure does not cause toxicity. That is possible only through taking too many supplements.
Most people older than 70 need more vitamin D than younger people.
“There’s a natural decline in stomach acids as we get older,” said Andrea Langston, certified dietitian nutritionist with Thrive Nutrition & Wellness in Amherst. “Stomach acid breaks down food and helps us absorb them.”
The amount of vitamin D one needs varies depending not only on age but also other health concerns and medication.
Where can we get vitamin D?
Primarily, it’s through the UVB radiation in the sun. While too much exposure can cause skin cancer, 20 minutes’ exposure a few times in a week suffices for generating vitamin D.
Commercially processed milk and other fortified products such as most boxed breakfast cereals contain vitamin D. Milk processed by an on-farm creamery may not have vitamin D added.
“There’s not a ton of dietary ways to get vitamin D,” Langston said.
She mentioned egg yolks, fatty fish like salmon and shellfish and mushrooms as naturally occurring dietary sources.
“The only thing is, it’s not super dependable in terms of how much you’ll be getting,” Langdon said. “It varies with animal products based on what they’re exposed to.”
So Why Do I Have Vitamin D Pills?
Unfortunately, doctors do not prescribe a vacation to a sun-soaked island for their patients deficient in vitamin D. Instead, it’s a supplement providing 50,000 international units (IUs) of vitamin D per dose. Over-the-counter vitamin D provides at most 10,000 IUs.
Vitamin D helps the body absorb nutrients. Vitamin D deficiency can cause rickets in children and in adults, hypoparathyroidism, osteomalacia, hypocalcemia, or bone diseases, which is why a prescription is sometimes necessary.