The 3 nutrients that can help you if you're feeling fatigued:

CINCINNATI (WKRC) – We’re learning that one of the after-effects of COVID-19 can be crushing fatigue.

Fatigue can impact all of us whether we have had this virus or not. If you do have the virus, recovery may take a while.

"It's probably a little longer than influenza,” said Dr. Stephen Cleves, an internal medicine specialist at TriHealth. “Probably a little longer than your mild to moderate bacterial pneumonia. It's like a severe -- both lungs -- what we would call bi-lateral pneumonia. Those take two or three months sometimes before you feel normal. The bad COVID cases are following kind of the same pattern."

The good news is that whether you’ve had the virus, if your energy is lagging, three nutrients may help you fight fatigue. It’s suggested if you are feeling tired, you ask your doctor to test you for these to see if you are low in them.

The first nutrient, iron, is found in a lot of breakfast foods, such as eggs. It’s also found in red meat -- in moderation -- and leafy greens. A study in the American Journal of Hematology found as many as 1 in 10 of us may be low in iron as we get older.

Magnesium is found in vegetables. It’s the second fatigue-fighting nutrient. It’s important for heart and nerve function to help energy. It is also found in whole grains, nuts and beans.

Finally: B-12. It’s only found in animal foods and a common low nutrient that can impact energy.

If you don’t eat these foods, you might be low, but you also may need this supplement this nutrient if you’re low. Lack of vitamin B-12 is also caused by an absorption problem in some people. If that’s the problem, no matter how much food you eat, you won’t feel better. Instead, ask your doctor about vitamin B-12 shots or some other way to get it into your body. Not enough of it can make you feel exhausted. It can also lead to cognitive changes in your brain