Vitamin D is a critical nutrient for your body. It affects many of your body’s systems and functions, and when you are not getting enough, you run the risk of having significant health problems. The risk of developing problems like depression, Alzheimer’s disease, cardiovascular disease, cancer and other problems can all be increased by having low vitamin D levels.

Even though it is so important, there are a surprising number of adults that are considered vitamin D deficient. More than 75% of adults fail to get enough vitamin D. Here are some great ways to increase the amount of vitamin D in your body.

1. Get outside.

Dr. Michael F. Holick, Ph.D., M.D., a professor of medicine at Boston University School of Medicine and the author of The Vitamin D Solution, states, “Sunlight is your best source for D.” He developed an app, called “dminder,” that can help you learn about how much vitamin D you are probably getting, based on your location, your skin type, and the time zone you live in.

2. Try supplements.

Holick recommends that adults get even more than the Institute of Medicine recommends, when it comes to vitamin D. He recommends that adults get 1,500 to 2,000 IU per day, for best results. This is considered to be a safe level, and provides your body with enough vitamin D to take care of all of the important functions that it is known to help with. Vitamin D is found in most multivitamins, but taking a supplement would likely be necessary to reach the levels recommended by Holick.

3. Eat more wild salmon.

It can be difficult to get enough vitamin D from diet alone. But, eating wild salmon can certainly put a huge dent in how much you need, because it contains high levels of vitamin D. Eat the wild varieties of salmon, with the more reddish flesh, and you can get about 450 IU for every 3 ounces that you consume. Add a tablespoon of cod liver oil, if you can stand the flavour, and you will be well on your way to making your daily dose.

4. Eat more mushrooms.

Surprisingly, mushrooms contain high amounts of vitamin D when they are exposed to UV light sources, much like the human body. When you eat mushrooms that are labeled as having vitamin D, you can raise the levels in your body, by getting about 400 IU per serving.

5. Add fortified foods.

Certain foods are given a boost of vitamin D when they are processed, such as orange juice, milk, and breakfast cereals. You can get about 100 IU from a serving of these vitamin D fortified foods.

It’s likely that you are vitamin D deficient, but you should check with your doctor before adding too much, so you know just how much you need. These suggestions can help you get the amount your body needs for best results.