Vitamin D Supplements: Do You Need Them?

Estimates from recent years suggest an increase in deficiencies and insufficiencies associated with vitamin D in certain populations. Nicknamed the sunshine vitamin, it plays an important role in various functions of the body.

The nutrient helps with the absorption of calcium which means a deficiency could lead to weaker bones over time. Low levels have also been linked to negative effects on mood, joint health, immune function, to name a few.

As you may know, the vitamin is largely derived via exposure to sunlight. Midday is said to be the best time to get vitamin D, as stated by Healthline, since the sun is at its highest point.

Though few in number, there are also dietary options including egg yolks, mushrooms exposed to the sun, fortified products, and oily fish such as salmon, mackerel, herring, and sardines.

Food and sunlight aside, the other available source comes in the form of supplements — but do you need to take them?

Dr. Clifford Rosen of Tufts University said it is "generally better" to get the vitamin from sun exposure and dietary sources than from supplements. Speaking to CNN, he also noted a lack of causality in studies linking vitamin D deficiencies with serious illnesses.

In other words, it is possible that sick people end up with reduced levels of the nutrient rather than the other way around. So we need better quality research before we can consider associations to the likes of heart disease and colon cancer

Another issue is that one could end up with too much vitamin D when taking supplements. In a study based on United States survey data gathered between 1999 and 2014, researchers found a 2.8 percent increase in the number of people taking "potentially unsafe" amounts of the vitamin.

"Megadoses of vitamin D can cause a buildup of calcium in the blood, causing nausea, vomiting, poor appetite, constipation, weakness, and weight loss," Madeline Basler, a registered dietician nutritionist with Real You Nutrition, told Reader's Digest.

The bottom line is to prioritize sunlight and food before considering the option of supplements. In most cases, both of those sources are enough to fulfill your daily recommended intake — 600 or 800 IU per day based on your age.

Individuals who face dietary restrictions or are unable to get enough sun may want to speak to a doctor as they are at the highest risk of having low levels of the nutrient. Some possible symptoms of vitamin D deficiency are fatigue, mood problems, erectile dysfunction, joint pain, insomnia, and infections. 

If needed, they will be prescribed supplements and asked to make a few lifestyle changes as well. There is a risk of going over the upper limit if supplements are taken without the guidance of a medical professional.