You probably already know that if you undercook some foods like meat or poultry, you run the risk of bacterial infection. But if you overcook your food, the risks may be equally great – although not immediately noticeable.

Overcooking foods by frying, grilling, or excessive broiling produces substances called advanced glycation end-products (AGEs). AGEs are created by rapid, high-heat cooking. What’s the big deal, you may ask? After all, most of us have eaten a slightly charred chicken breast, or even veggies that turned black from over-grilling, and we didn’t feel any ill effects. Well, AGEs are pro-oxidants (they increase oxidative stress in the body, which means your body generates more free radicals that interfere with normal body processes). Think of rust slowly oxidizing metal and eating it away.

Generally, the longer you cook a food, the greater the nutrient loss. This occurs because of the longer time in which chemical reactions can occur. Some vitamins are more sensitive to the effects of cooking. You will quickly deplete the amount of vitamin C in your foods with normal cooking, let alone overcooking. This is due to the chemical nature of this nutrient. The U.S. Department of Agriculture provides an extensive listing of the percentage of nutrients maintained based on food type and cooking method.  High heat zaps nutrients. Did you know that over-frying your eggs changes the protein structure and makes them less beneficial? The same goes for veggies: overcooking your broccoli zaps vital nutrients.

How you prepare your foods will also impact their quality. Some vitamins, such as the B-complex vitamins and vitamin C, are water soluble, meaning they dissolve in water. If you cook these in water, you will, in effect, leach the nutrients from the food into the cooking water. The longer you cook them, the greater the nutrient loss will be. Unless you use the cooking water in your recipe, you are literally throwing nutrition down the drain. Microwaving foods minimizes nutritional loss, even with overcooking, simply because it is a quicker preparation method. For example, baking a whole acorn squash in the oven takes 45 minutes or more. In the microwave, it is cooked in only 7 to 10 minutes.

Don’t kill your food by overcooking. Lightly steam vegetables to preserve maximum nutrient content. When grilling anything, turn it often to prevent charring. When broiling or grilling meat, marinate it first to help prevent charring. If frying eggs, use low heat and cook them just long enough to kill any bacteria.