What it is: 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 to use the calcium you get from food or supplements. RA tends to be worse in people who are low in vitamin D, but it isn’t clear why.
How much you need: All adults up to age 70 should get 600 international units (IU) of vitamin 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. Your doctor can check your vitamin D level with a blood test.
How to get it: It’s added to almost all milk and to some orange juices, breakfast cereals, and soy and nut milks. (Check the label). Egg yolks, salmon, tuna, and sardines naturally have some vitamin D. Your body also makes vitamin D in sunshine, but because you’ll need to wear sunscreen to protect your skin, you might not want to rely on sun exposure 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 what 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 flaxseeds, leafy green vegetables, nuts, canola oil, and soy oil, have ALA, another type of omega-3 fatty acid.
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.