But vitamin D is crucial for many other reasons, including helping the immune system function, according to the National Institutes of Health. This may explain the connection between vitamin D and psoriasis, a disorder of the immune system. Researchers have found that people with plaque psoriasis often have lower than normal levels of vitamin D, says the Mayo Clinic. Not having enough vitamin D doesn’t necessarily cause psoriasis, says Suzanne Olbricht, MD, the chief of dermatology at Beth Israel Deaconess Medical Center in Boston. But vitamin D deficiency may be a contributing factor, because it impairs the immune system’s ability to keep skin healthy. One way to get more vitamin D, the so-called “sunshine vitamin,” is to get outside for 10 minutes at midday, according to the National Psoriasis Foundation (NPF), since enzymes in skin can convert UV rays to vitamin D. But anyone with psoriasis needs to be especially careful about excessive sun exposure; a study published in the Journal of Drugs in Dermatology in October 2019 suggested a link between psoriasis and nonmelanoma skin cancer, particularly for people who’ve been treated with phototherapy or immunosuppressive medication. Fortunately, there are multiple ways for people with psoriasis to get the recommended daily dose of vitamin D, which according to the American Academy of Dermatology is 600 international units (IU) for people ages 1 through 70 and 800 IU for adults 71 and older. Here are six simple — and safe —ways to get more D.

Consume Fatty Fish

The most efficient way to get enough vitamin D in your diet is by eating fatty fish, like salmon, tuna, trout, mackerel, and eel. You can get more than two-thirds of your daily dose of vitamin D from one 3-ounce (oz) portion of sockeye salmon. Fish doesn’t have to be fresh-caught to be beneficial. Canned light tuna, for example, packs about 150 IU of vitamin D for every four ounces. Canned sardines offer a little more than 40 IU of vitamin D for every two you eat. Eating oily fish may also have a side benefit if you have psoriatic arthritis. This type of fish is also rich in omega-3 fatty acids. According to the Arthritis Foundation, omega-3 fats can help ease joint swelling and pain by tamping down inflammation. Fatty fish can be high in mercury, though, so if you’re pregnant or nursing, speak to your doctor about how many servings per week you can safely consume.

Drink Milk

An 8 oz glass of milk provides 100 to 125 IU of vitamin D, whether it’s nonfat, reduced-fat, or whole milk — so opt for the healthier low-fat or nonfat choices. If you’re allergic to cow’s milk, you can get your daily dose of D from milk alternatives such as soy milk, almond milk, or rice milk. Just read the label on the carton, because the amount of vitamin D in an 8 oz serving can vary.

Switch to Fortified Orange Juice

Oranges are known as a great source of vitamin C. But when you’re buying orange juice, look for brands that are fortified with vitamin D; an 8 oz glass should give you around 100 IU.

Eat Eggs More Often

Egg yolks are an excellent source of vitamin D — about 40 IU each. Be careful to eat them in moderation if you are sensitive to dietary cholesterol, says the American Heart Association.

Start Your Day With Fortified Cereal

Fortified cereal is another easy way to get your daily fill of vitamin D. Look for a low-calorie fortified hot or cold cereal, and read the package label to determine how much vitamin D you will get and what’s considered a serving size. Bonus points if you top your bowl of cereal with fortified milk and pair it with a glass of fortified OJ.

Talk to Your Doctor About Vitamin D Supplements

The NPF says the evidence that vitamin D supplements can ease psoriasis symptoms is weak, and that the best way to get more vitamin D is through food. But if you find you can’t bump up your intake of vitamin D–rich foods, or if you have psoriatic arthritis, ask your doctor if taking a vitamin D supplement might make sense. Just be sure not to turn a vitamin deficiency into vitamin overload. Excessive amounts of vitamin D can affect your blood pressure, cause muscle weakness, and lead to gastrointestinal problems.

Try a Vitamin D Ointment

Vitamin D topical ointments are often used to counteract the abnormally fast regeneration of skin cells that can lead to psoriasis plaques. Prescription ointments or creams that contains active or synthetic vitamin D3 include Dovonex (calcipotriene) and Vectical (calcitriol), says the NPF. “If you put something on the skin that slows growth, it may cause the plaques to become thinner and less scaly,” says Richard Gallo, MD, PhD, the founding chairman of the dermatology department at the University of California in San Diego. Apply a thin layer to psoriasis plaques once or twice a day, or as recommended by your doctor. These medications can be used alone or with topical corticosteroids. Most people notice an improvement after using them for two weeks, according to the American Academy of Dematology.