A case of brown eggs are in focus.
Get your vitamin D the natural way to keep the winter blues at bay. (For Spectrum Health Beat)

Getting your share of vitamin D, sometimes called the “sunshine vitamin,” could make or break your mood this winter.

Did you know that a deficiency of D may be linked to multiple medical issues such as obesity, diabetes, hypertension, cancer and depression, including seasonal affective disorder? All true.

Sunscreen is good, but…

SAD is usually treated with light therapy and other techniques, but research indicates that getting enough vitamin D may also be a factor.

In a perfect world, you would get plenty of vitamin D when your skin is exposed to the sun. But long winters in northern climates and wise use of sunscreen leave many of us shortchanged.

“Statistically, about half of us are deficient in vitamin D and our levels are lowest from February through April,” said Jessica Corwin, MPH, RDN, community nutrition educator for Spectrum Health Healthier Communities. “Thankfully, doctors are taking note and testing us for vitamin D so people can know whether they need to change their diets or take supplements.”

Adults between ages 19 and 70 should get 600 international units (IU) per day, and the recommendation goes up to 800 for those 71 and older.

“Vitamin D is readily available in ‘fortified’ food, including most cow’s milk, almond milk, breakfast cereal, meal-replacement bars and even orange juice,” Corwin said. If you prefer to get your dose of the sunshine vitamin without fortified foods, however, it takes more effort.

There’s a very short list of foods that are rich in vitamin D naturally. It includes:

Oily fish

Trout, salmon, swordfish, mackerel, tuna, herring or sardines are all great choices. Fresh fillets and canned fish are similar in nutritional value, but fish canned in oil with small bones is often less expensive and you’ll reap the benefits of added omega-3 and calcium.

You’ll get about 425 IU in a 3-ounce serving of salmon or 547 IU in a 3-ounce serving of mackerel. Canned tuna has about 154 IU in 3 ounces, while sardines will give you 270 IU in 3.5 ounces.

Cod liver oil and fish oil tablets are a traditional source of vitamin D, but check the label carefully, Corwin warns. “Some are fortified with vitamin D, and some have nearly zero.”

Certain mushrooms

Not all mushrooms are created equal.

Some have been exposed to ultraviolet light, which boosts their vitamin D content. Avoid little white button mushrooms. Instead, look for portabella, shitake or other, more exotic varieties. For example, shitake mushrooms typically have 40 IU per cup.

Beef or calf liver

Not everyone is a liver lover, but if you can tolerate it, you’ll reap the vitamin D benefits.

Keep in mind, however, that although liver can be nutrient-rich, it’s also essentially a sponge that removes toxins from the body so some people prefer to avoid it. The quality depends on the diet of the livestock (grass-fed is better).

You’ll find about 42 IU in a 3-ounce serving.

Egg yolks

Eggs are relatively inexpensive and easy to prepare—think hard boiled, scrambled or a whole-egg veggie omelet (egg whites don’t have vitamin D).

Each egg has 41 IU.

Check your facts

There’s a lot of misinformation online today, so if you want to check your favorite food’s vitamin D level (or any other nutrient), you can create your own report using the USDA database.

We all absorb and convert vitamin D, so Corwin recommends asking your doctor to check your levels with a simple blood test. Once you’ve changed your diet, ask to get a follow-up test after a few months to see if it’s making a difference.

If you’re low, vitamin D supplements are an easy and quick way to get your full dose if you use them correctly.

“Don’t go overboard,” Corwin said. “You don’t want to take too much because it can be toxic.”