What it is: It’s a nutrient that your bones, muscles, and immune system need. Your doctor can check your vitamin D level with a blood test.
Why you need it: Your body needs it in order to use the calcium you get from food or supplements. RA tends to be worse in people who are low on vitamin D, but it’s not clear why.
How much you need: All adults up to age 70 should get 600 IU of D per day. Starting at age 71, you should get 800 IU per day. You may need more if you are low in vitamin D.
How to get it: It’s added to almost all milk and to some orange juices, breakfast cereals, and soy or nut milks. (Check the label). Egg yolks, salmon, tuna, and sardines naturally have some vitamin D in them. Your body also makes vitamin D from sunlight, but because you’ll need to wear sunscreen to protect your skin, you might not want to rely on the sun for your vitamin D.
Omega-3 Fatty Acids
What they are: Omega-3 fatty acids are a type of healthy fat.
Why you need them: Omega-3s may help prevent heart problems linked to RA, and high doses might ease RA symptoms like morning stiffness.
How much you need: There’s no RDA (recommended dietary allowance) for omega-3s, so ask your doctor how much you need. Studies show that people with RA have lower-than-average levels of EPA and DHA, two omega-3 fatty acids.
How to get it: Your body can't make omega-3s. You can get EPA and DHA from salmon, tuna, sardines, and other fatty fish. (Many experts recommended eating fish at least twice a week.) Some plant foods, such as flax seeds, leafy green vegetables, nuts, canola oil, and soy oil, have ALA, which is another type of omega-3 fatty acid. Or you can take a supplement.
Other Vitamins and Minerals
You may have heard that not getting enough vitamin C, vitamin E, magnesium, zinc, and selenium can affect RA symptoms. While your body needs all of these, there’s no proof that taking extra helps RA.