4 Facts Doctors Need You to Know About Taking Vitamin D - The Beet

Vitamin D has been all the rage lately, and it’s easy to see why. The sunshine vitamin delivers many health benefits, such as strengthening bones, elevating your mood, and bolstering the immune system (even against COVID-19 symptoms).

You might worry you’re not getting enough vitamin D and look to supplements or nutrition to boost your levels. However, many surprising vitamin D benefits are still up for grabs despite all the hype. So read on to discover some fascinating vitamin D facts that might surprise you, according to experts.

4 Surprising Facts About Vitamin D

1. Excessive vitamin D intake can cause kidney stones.

Supplementing excessive amounts of vitamin D can have adverse side effects, including kidney stones. This occurs because too much vitamin D can cause high calcium levels, which over time can lead to kidney stones. Other side effects of consuming toxic vitamin D levels include nausea, confusion, and fatigue.

Your susceptibility to kidney stones from vitamin D may be related to your genes. Dr. Jeffrey Bland, Ph.D., immunity expert and founder of Big Bold Health, tells The Beet, “Vitamin D increases calcium absorption in the body. Supplementing high doses of vitamin D has been associated with increased risk of calcium-related kidney stones in people who have a history or genetic risk of kidney stones.” Therefore, it's essential for anyone living with kidney disease who supplements vitamin D to get regular vitamin D blood panels to ensure their levels are in a healthy range.

If you take vitamin D supplements, pay close attention to the dosage to ensure you’re not reaching toxic levels. According to the NIH, a daily amount of 800 IU per day is sufficient. However, for people who don’t get much sun exposure (i.e., those who live in northern latitudes, frequently wear sunscreen, or don’t get outside much), supplementing with doses of 1,000 to 2,000 IU may be appropriate. Reminder to always talk to your healthcare provider before taking a vitamin D supplement.

2. Aging reduces the skin’s ability to produce vitamin D

A 2014 study demonstrated that aging impacts your skin’s natural ability to produce vitamin D in the presence of sun exposure. Dr. Bland says the overuse of sunscreens also reduces vitamin D production in your skin.

So how much sun exposure does your skin need to produce sufficient amounts of vitamin D? Dr. David Bissonnette, Ph.D., associate professor of nutrition at Minnesota State University, explains, “For sun exposure to be a significant contributor of vitamin D, a person would need to have their legs, face, arms or back, exposed to ultraviolet light for between five to 30 minutes between 10 AM and 3 PM without the use of any kind of sunscreen.” However, he adds, “Currently, no studies have determined the minimum amount of sun exposure necessary to generate vitamin D with minimal risk of skin cancer.”

3. Vitamin D levels affect your sexual health

It’s not common knowledge, but vitamin D deficiency can impact your performance in the bedroom. Vitamin D increases sperm motility, improves fertility, and boosts testicular function to produce sex hormones, says research published in The World Journal of Men’s Health.

“Research has found that low vitamin D status is associated with decreased sexual health in both men and women,” says Dr. Andrea Paul, MD, co-founder of Health Media Experts and Medical Advisor at Illuminate Labs. “There is also medical research suggesting that optimal vitamin D levels are necessary for erectile function.”

As for women, a 2019 study found an association between vitamin D deficiency and sexual dysfunction, including symptoms of low sex drive, lack of arousal, and pain during intercourse. Dr. Bland tells The Beet, “In females, vitamin D is used by the ovaries for maintaining proper sexual function. However, there is no conclusive evidence showing vitamin D alters female sex hormones.”

4. Vitamin D status affects urologic health

Urology relates to the body parts involved in sexual health, such as the prostate and testicles. Urologic health also consists of the body parts responsible for producing, storing, and eliminating urine, such as the bladder, kidneys, and urinary tract. Dr. Bland explains, “Because vitamin D influences calcium absorption and utilization, it can affect the amount of calcium excreted in the urine. Therefore, a well-balanced intake of vitamin D is important in promoting proper calcium utilization and urinary tract health.”

More and more research is revealing a correlation between vitamin D deficiency and several urologic issues, including overactive bladder, urinary tract infections (UTIs), prostate gland enlargement, and even bladder cancer. Since vitamin D is fat-soluble, it doesn’t get excreted through urine like other vitamins. Therefore, supplementing toxic vitamin D levels can cause your blood to retain too much calcium and lead to hypercalcemia (excessive amounts of calcium in the blood), resulting in an overactive bladder, according to research published in the peer-reviewed Endocrine Abstracts.

Adequate vitamin D levels can boost your immunity against recurring UTIs. A 2019 study demonstrates how low vitamin D levels are associated with an increased risk of UTIs in children and adults. In addition, vitamin D deficiency is associated with prostate gland enlargement, which has many uncomfortable urinary symptoms, such as frequent urination, difficulty urinating, and an inability to empty the bladder.

Bottom line: Vitamin D is essential for many bodily functions.

Besides vitamin D’s well-known benefits of strengthening our bones and supporting the immune system, the sunshine vitamin is also associated with kidney health, aging skin health, sexual health and function, and urologic health. Ensure you get reasonable amounts of sun exposure and consume at least 800 IU of vitamin D per day for optimal health. As with any supplement, we recommend you speak with your healthcare provider before starting a vitamin D supplement.

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