If antioxidants are good for you, then it makes sense to increase the antioxidants you consume through your regular diet with a flood of supplements, right?

That may not be so, according to some recent research. The name “antioxidant” refers to chemicals that stop molecules from oxidizing. Oxidation occurs when a molecule loses or gains an electron. A classic example is rust: When iron reacts with water and oxygen, it corrodes, turning into rust.

Our cells don’t rust, but oxidation can lead to damage to the cell. However, a small amount of cell damage can be a good thing. Damage in cells can trigger the body to create pathways to protect against oxidation, forming its own antioxidants.

A Norwegian study examined healthy adult men and women, most of whom were cyclists and runners. After taking muscle biopsies, blood draws and testing the volunteers’ endurance, the researchers divided the volunteers into two groups.

One group received placebo pills and the second group took 1,000 milligrams of vitamin C and 235 milligrams of vitamin E each day. At the end of an 11-week training program, each group had increased endurance and strength. But the placebo group had increased biomarkers indicating their bodies were making more mitochondria, a marker of health and fitness. However, the group taking antioxidants had fewer of these biomarkers.

Another study of 32 men and women, half of whom took vitamins E and C and half of whom received a placebo pill, looked at muscle strength after a course of weight training. Although each person’s muscles increased in size, only the group who took the placebo pills increased in strength.

When it comes to antioxidant intake, the old adage seems to hold true: You can have too much of a good thing.