America may have a vitamin D deficiency problem.

As a supplement, vitamin D has been a staple on drugstore shelves for years—and its popularity is only growing.

It is the market price in the US. It is expected to reach 1.3 billion dollars By 2025, studies show that a A big jump Vitamin D deficiency has been researched for the past two decades, and over-the-counter supplements can support bone health, muscle function, and the immune system.

Supplement took on a new life last year, time people He started taking vitamin D pills As a preventive measure against covid. Medical professionals today I generally agree: Vitamin D does not prevent you from catching the virus. And while scientists are still trying to figure out if it can reduce the severity of infections, because of its immune-boosting benefits, it’s certainly not a substitute for disease. Vaccination.

But Vivid’s concerns aside, doctors have mixed opinions on the supplement. Some say it’s a harmless everyday pill that only helps many Americans when taken in moderation. Others argue that this is largely a wasteful expense – and in most cases it is irresponsible to even test patients for vitamin D deficiency.

“This is a very difficult subject. There is really no consensus. There are no large-scale good studies on vitamin D without any conflict of interest.” Dr. Neha VyasA family medicine physician at the Cleveland Clinic tells CNBC Make It. “You really have to be careful.”

“There’s really no need to screen low-risk or asymptomatic people for vitamin D deficiency,” he says. Dr. Kendall MoseleyMedical Director of the Johns Hopkins Metabolic Bone and Osteoporosis Center. “One of the reasons for the ‘increased’ prevalence of vitamin D deficiency over the last five to 10 years is not that we are all actually becoming vitamin D deficient. We are now looking for more.”

A significant study Published last month He supports Moseley’s position in the New England Journal of Medicine. Researchers studied 25,871 participants – men 50 and older and women 55 and older – and determined that vitamin D supplements had no significant effect on the health of “generally healthy middle-aged and older adults.”

If you’re breaking bones with simple activities, feel bone pain when touched, or have enough muscle pain or weakness that you can’t comfortably get out of a chair, you should talk to your doctor about a possible vitamin D deficiency, Moseley says. . General fatigue and low mood can be associated with blemishes, she adds – and you may be at risk if you have darker skin or spend the winter in high latitudes.

Moseley notes that if you have any of these symptoms, it’s unwise to self-medicate with over-the-counter supplements — because if you’re seriously deficient, you’ll need to take cases.

But Weiss says you shouldn’t be surprised if your doctor sees vitamin D as the immediate culprit: Many of the symptoms associated with vitamin D deficiency are also linked to other, more serious health conditions.

“As scientists, we have to be very careful about how we talk to our patients,” Vyas says. We don’t want to say, “Oh, you’re tired,” or, “Oh, you’re stressed, let me check your vitamin D levels.” Because there is so much. [potential] For that reason.”

If your doctor doesn’t think you’re particularly at risk for severe vitamin D deficiency, or if your symptoms don’t warrant a diagnosis, the way forward is basically risk with reward.

Mild deficiencies are “very common” because most people don’t get enough sunlight in their daily lives to absorb a healthy amount of the vitamin, he says. Dr. Jad Sfeir, a Mayo Clinic endocrinologist. They go largely undetected, he says: Most people could live their entire lives with a small deficit and never know.

Still, even minor mistakes can have long-term consequences. “Ultimately, it puts your bones at risk of breaking and breaking more easily,” says Sfeir. “Osteoporosis can go completely undiagnosed for years until we find it on a bone density scan – usually after menopause in women and usually after age 60 or 70 in men.”

Sfeir says that taking 600 to 800 international units (IUs) of vitamin D per day can safely address the issue. If you can get that completely from your diet, he says, you don’t need supplements — so watch how much vitamin D you get from sources like fortified milk and orange juice, or fatty fish like salmon or mackerel.

Just be careful about adding over-the-counter supplements to the mix. Exceeding a total of 4,000 IUs per day can increase calcium levels in your blood and urine, putting you at risk of dangerous levels of toxicity, says Sfeir. This can cause symptoms such as kidney stones, nausea, vomiting, cognitive changes, memory impairment and kidney failure, Moseley added.

These days, if you search for “vitamin D” on Amazon, you’ll see several potentially dangerous options before you find anything below Sfeir’s 600 IU figure — anywhere from 2,000 IUs to 5,000 IUs per pill. Moseley also notes that vitamin D can be found in other supplements, from beauty supplements to energy pills.

In a high-profile example published last month in the medical journal BMJ Case Reports, there was a British man. Hospitalization for eight days – 150,000 IU per day vitamin D one month after starting medication.

“It can take a year or more for things to normalize. In more severe cases, patients may need to go on dialysis,” Moseley said. “Correcting excess vitamin D is more difficult than correcting low vitamin D.”

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