In recent years, research into Vitamin D has shown just how important it is for our health. It has found that having low Vitamin D levels are associated with a higher risk of heart disease, diabetes, cancer, mood disorders, dementia, and other diseases.
People have taken note and the vitamin is having its moment in the sun, so to speak. Vitamin D supplements and screening tests have become far more popular but, with them has come the rise of something else: too much of a good thing.
Vitamin D has been called the sunshine vitamin because your body has the ability to produce it internally after exposure to the sun. Produced in the kidneys, it enters the bloodstream where it has long been known to help the body absorb calcium and phosphorous, helping to build strong bones.
If a person doesn’t have enough vitamin D, their bones can become thin, brittle or misshapen. Deficiency can cause rickets for children, and osteomalacia and osteoporosis in adults, especially the elderly.
Wanting To Do Right
It’s no surprise then that people who want to maintain good bone health look toward Vitamin D supplements in addition to taking calcium. But those people should know that the science is still out on whether or not supplementation helps.
“Research on Vitamin D and calcium supplementation has been mixed and, especially when it comes to randomized clinical trials, has been generally disappointing to date,” says Dr. JoAnne Manson of Harvard Medical School.
Correlation Is Not Causation
While some studies have found an association between low levels of Vitamin D and various diseases, Dr. Manson said, it hasn’t been conclusively shown that the low Vitamin D levels actually cause those diseases.
A person with a serious illness may have a Vitamin D deficiency but that may be because they spend little time outdoors being physically active, or because of a poor diet. Both of those things could be the cause of many diseases and of a Vitamin D deficiency at the same time.
Many diseases cause inflammation, which can reduce levels of Vitamin D in the blood. Obesity, which has links to a number of diseases, can also reduce blood levels because your body stores Vitamin D in fat tissue, meaning less shows up in blood tests.
“Thus, a low Vitamin D level may be a marker for other conditions, but not necessarily a direct cause of disease,” Dr. Manson said. Still, people continue to take Vitamin D supplements in hopes of preventing or helping in treating of a number of diseases. And though the research is inconclusive, there are signs that point toward supplementation being helpful, so long as it’s done in the right amounts.
Enough Is Enough
But some people seem to be overdoing it. In a national survey that gathered data between 1999 and 2014, researchers found a nearly 3 percent increase in people taking more than 4,000 international units (IU) of Vitamin D each day — a potentially unsafe amount. There was also a nearly 18 percent increase in the number of people taking over 1,000 IU, which is still beyond the recommended dose of 600-800 recommended by doctors.
All Things In Moderation
“More is not necessarily better,” said Dr. Manson. “In fact, more can be worse.” One study showed that intake of very high doses of Vitamin D in older women was associated with more falls and fractures.
And in rare cases, taking a supplement with too much vitamin D can be toxic. That leads to hypercalcemia, a condition where calcium builds up in the blood to excessive amounts, which can lead to deposits in the arteries or soft tissues. For women, it may also predispose them to kidney stones.
Thankfully, there are a few simple guidelines you can follow to ensure that you get a good amount of Vitamin D in your system. First, keep track of the amount of vitamin D put into whatever supplements you take. For most people 600 to 800 IU is an adequate amount to take.
Different For Some
There are some people who require a higher dosage, including those with bone health disorders or conditions that interfere with the absorption of Vitamin D or calcium. For those people especially, it’s important to follow the second guideline.
Talk To Your Doctor
The second guideline is to follow your doctor’s recommendations, and make sure your doctor knows if you are supplementing your diet with Vitamin D or anything else. “Many people are taking high-dose supplements on their own and their doctors may not even be aware of it,” said Dr. Manson.
Finding The Right Amount
Work with your doctor to figure out if supplement use is right for you, and if so, which supplements you should be taking. After talking with a health professional, many people find that they don’t even need supplementation so long as they’re getting the right levels of Vitamin D from their diet.
The last guideline is, if possible, to get your Vitamin D from food, rather than from supplements. Though it’s not found in most foods, salmon, tuna, sun-dried mushrooms, and eggs are all good sources. You can also find products like milk or orange juice that have been specially fortified with Vitamin D at any grocery store.
Location, Location, Location
There are a few different factors that may put you at risk of having low Vitamin D, and the most unexpected one is where you live. People living above 37 degrees in the northern hemisphere and below 37 degrees in the southern hemisphere are at a greater risk for deficiency because they may not be getting enough sun to produce sufficient Vitamin D during winter months.
Other Risk Factors
Your ability to produce Vitamin D also decrease with age. People over the age of 65 produce just a quarter of what they did when they were in their twenties. People with darker skin also typically have lower levels of Vitamin D than lighter-skinned people. Americans of African descent, for example, have roughly half the Vitamin D in their blood than Americans of European descent.
If you suspect that you have a Vitamin D deficiency, there’s a surefire way to be sure. A simple blood test can easily show you. However, like Vitamin D supplements, Vitamin D tests have proven to be overused in recent years.
“Vitamin D testing is one of the top Medicare lab tests performed in the United States in recent years,” said Dr. Manson. “This is really surprising for a test that is recommended for only a small subset of the population.” While you should definitely speak with your doctor, you should know that if your diet is good and you don’t suffer from any diseases or disorders, you should be fine.