The Sunshine Vitamin: Get Your Vitamin D

Experts agree that vitamin D is essential for your many aspects of your health, but the latest research questions vitamin D as a panacea for cancer and heart health. What you need to know now about vitamin D: how much you need, where to get it, and more.

Chances are, you’re confused about vitamin D — whether you should take supplements, how much you should take, and how it helps you. Some recent studies tout vitamin D as the new supervitamin while other research and experts have questions its wide-ranging benefits and even acknowledged the potential side effects from too-high doses. New research published today in the Annals of Internal Medicine is the latest in a slew of studies to cast doubt on the benefits of vitamin D supplements.

After a review of 19 trials and 28 observational studies, researchers found thatvitamin D supplements alone were not effective in reducing bone fracture risk, as previously thought. But because vitamin D promotes the body’s absorption of calcium, researchers concluded there is evidence that a combined vitamin D and calcium supplement can reduce fracture risk and boost bone health. The same research review found limited data to suggest that vitamin D can reduce cancer risk. In a separate review of vitamin D studies also out today, researchers concluded that there’s still no evidence that vitamin D supplements can reduce the risk of heart disease.

The U.S. Preventive Services Task Force (USPSTF) is set to analyze this new research and release updated recommendations for vitamin D supplements. Currently, the Institute of Medicine (IOM) recommends adults consume 600 international units (IU) of vitamin D daily, less than what is in two three-ounce servings of salmon, which provides 894 IUs. After age 71, the IOM recommends increasing intake to 800 IU. Still, some experts view these levels as too low, and the right dosage of vitamin D remains unclear.

As the debate around the importance of vitamin D supplementation wages on, remember that exposing yourself to limited amounts of sunlight and adding D-rich foods to your diet remain the most fail-safe ways to reap the benefits of vitamin D. Here, what you need to know now.

The Importance of Vitamin D

In addition to helping the body absorb calcium, vitamin D also regulates the body's calcium levels in the blood, as well as levels of the mineral phosphorus, which also helps to promote healthy bones and teeth.

Vitamin D deficiency can be serious, causing bones to deteriorate and weaken. In adults, a vitamin D deficiency can lead to the bone condition osteoporosis and, in children, it can cause rickets — soft and weak bones. Although more research is needed, some studies have suggested that vitamin D may have many other beneficial effects, such as boosting the immune system.

Where to Get Your Vitamin D

The body produces vitamin D on its own after exposure to sunlight. You can also take a vitamin D supplement or get vitamin D from certain foods though it can be challenging to get all the D you need from diet alone.

Foods rich in vitamin D include:

• Fish, such as salmon, mackerel, sardines, and oysters
• Vitamin D-enriched cereal
• Some eggs (but the hens must have been given vitamin D)
• Vitamin D-fortified milk or juice
• Margarine and butter
• Dairy foods including cream and cheese

The Vitamin D Conundrum

So just how much vitamin D do you need? It depends on your gender and age. Get too little vitamin D, and you’ll feel the effects of vitamin D deficiency. Too much of it — and your blood can contain too much calcium, harming your lungs, heart, or kidneys.

Many physicians are now testing vitamin D levels in their patients and results often show low vitamin D levels. Based on these results, doctors often recommend much higher supplement doses, often 1,000 to 2,000 IU a day. However, a 2010 Institute of Medicine expert panel said that laboratory tests for vitamin D are not standardized and results vary widely among labs. Vitamin D deficiency may be overestimated, the panel concluded, and most American don't need more than the recommended amount of this nutrient.

How to Boost Vitamin D Levels

To get enough vitamin D from the sun, you need to spend about 5 to 15 minutes in the sun, just three times each week, without sunscreen. Too much sun exposure can cause sunburn and increase the risk of skin cancer, so make sure you limit your exposure. Also, you can expose your arms and legs, but you should always protect your face with sunscreen. If you don’t feel safe in the sun, turn to your diet and a vitamin D supplement to get the vitamin D you need.

Remember that you still need vitamin D in the winter. For many people, especially those in northern climates, it’s hard to get enough sun during those months, and a supplement may be necessary. African-Americans and others with darker skin tones may also be less able to absorb enough sunlight for sufficient vitamin D production from the sun alone.