What is Vitamin D Good For Anyway?
Updated: Nov 6, 2018
Experts say we need the sunshine vitamin — here's why.
BY AMY CAPETTA Oct 19, 2018 www.womansday.com
Vitamin D is one of those nutrients that you hear a lot about. Experts say that you really need it for strong overall health, but it's likely that you're not getting enough of it. In fact, a 2009 report found that many Americans were deficient, even though it's a fat-soluble vitamin that our bodies produce when skin is exposed to direct sunlight.
What gives? Despite being able to soak it in via Mother Nature (that's why it's often nicknamed the sunshine vitamin), there are a few reasons why adults are having difficulties meeting the National Institutes of Health's recommended dietary allowance of 600IU (International Units). First, there's your day-to-day lifestyle: Wearing sunscreen, spending the majority of your day indoors, covering up during the colder months — all of these things limit our skin's opportunities to absorb the sun's ultraviolet rays, says Eudene Harry, M.D., medical director for Oasis Wellness and Rejuvenation Center in Orlando. If you have darker skin tones, it's even more difficult, as UV rays aren't as easily converted, she adds. And as we get older, everyone's ability to produce vitamin D slows down.
Which is why a lot of people then try to get their daily dose through food. The problem is that there aren't that many that naturally contain vitamin D, says Toby Amidor, M.S., R.D., author of Smart Meal Prep For Beginners. “The best sources are fatty fish (such as salmon, tuna, and mackerel) and fortified foods, including milk, orange juice, yogurt, soy beverages, and cereals,” she explains. Egg yolks, cheese, and beef liver contain smaller amounts, and mushrooms that have been exposed to UV light will offer trace amounts of the nutrient.
So it makes sense, then, that some people turn to supplements. Both Amidor and Dr. Harry agree that taking a vitamin D supplement is probably necessary for the majority of adults, but they emphasize that your physician can confirm that for sure — and determine your dosage — as a 2017 study found that a number of adults may actually be consuming an excessive amount.
Whether you’re hitting your daily dosage from the sun, your plate, a supplement, or a combination of all three, here are six health benefits your body can score from getting enough vitamin D.
1. It can strengthen your bones.
First and foremost, this vitamin is necessary in order for the body to absorb calcium, a mineral that is essential in bone formation. “As we get older, we are more prone to fractures and osteoporosis, and vitamin D helps to ensure that calcium is deposited into the right place,” Dr. Harry says. What's more: According to a review of 53 studies published in the journal The Cochrane Library, seniors who took a vitamin D supplement with calcium had a reduced risk of hip fractures.
2. It may improve muscle strength.
After looking at 116 healthy adults between the ages of 20 and 74, researchers realized that the active form of vitamin D, which your body makes when your skin is exposed to sunlight, was linked to lean mass in women; those with more muscle bulk were likely to have higher levels of the nutrient in their bloodstream. The same outcome was not seen in men, but now scientists are analyzing the role vitamin D plays in muscle building in larger clinical trials.
3. It can boost your immune system.
In an international study that looked at nearly 11,000 people over 25 clinical trials, researchers found that those with lower levels of vitamin D who then took a daily or weekly supplement were shown to cut their risk of an acute respiratory infection (such as pneumonia or the flu) and an upper respiratory infection (like a cold and sinus infection). A study published in Frontiers in Immunology also found that vitamin D could be therapeutic for those with an autoimmune disease, such as Lupus and multiple sclerosis, Dr. Harry adds.
4. It may lower your diabetes risk.
Study authors from the University of California San Diego School of Medicine and Seoul National University followed nearly 900 healthy adults over a 12-year period. Their vitamin D levels, as well as two measurements for diabetes — fasting plasma glucose and oral glucose tolerance — were recorded. Over that 12-year span, 47 people were diagnosed with type 2 diabetes and 337 were diagnosed with prediabetes. The connection? Those with higher blood serum levels of vitamin D had between one-third and one-fifth of the risk of developing diabetes compared to those with lower levels of the nutrient.
5. It may improve your chances of healthy pregnancy.
Researchers from the Eunice Kennedy Shriver National Institute of Child Health and Human Development uncovered two possible connections between vitamin D and motherhood. After analyzing several studies that involved women who were undergoing in vitro fertilization, they found that the females with higher levels of vitamin D also had higher rates of pregnancy. They also discovered that moms-to-be who had sufficient levels of vitamin D before conceiving were 10% more likely to become pregnant, and they had a 12% reduced risk of miscarriage once they were expecting.
6. It could reduce your risk of cancer.
Various studies over recent years suggest that vitamin D is associated with lowering your chances of developing different forms of cancer, including breast, colon, bladder, and liver. Plus, a September 2018 study published in Menopause, which looked at 600 women, found that post-menopausal females with obesity had an increased risk of vitamin D deficiency at the time they were diagnosed with breast cancer. Why does that matter? Those with higher levels of vitamin D during cancer treatment had a 50% lower mortality rate, so experts think there could be a connection between the nutrient and your chances of beating the disease — or even getting it at all.