Can cooking food change its nutritional value?

The beauty of home cooking is that you can create many different dishes with the same ingredients. For instance a green pepper could be a light crunchy addition to a savory salad, or it could be a killer side dish after a simple sauté. But, will changing the preparation of the pepper change the benefits we get from eating it?

We recently got this question from a viewer:

Dear Dr. Manny,

Do vegetables lost nutrients when they are cooked?



The answer is, yes. But while certain cooking methods can change the nutritional makeup of your fruits and vegetables, it can sometimes be for the better.
For example, when you cook tomatoes, the antioxidant lycopene becomes more concentrated. Lycopene is not only a compound that gives tomatoes its color, but it’s also been linked to lower risk of cancer, according to the American Cancer Society.

But on the other hand, sometimes crucial nutrients can be pulled out from the fruit or vegetable during the cooking process.

There are a few steps you can take to avoid losing nutrients while cooking.  It is important not boil or steam or cook vegetables for too long. Lightly cooking or blanching the vegetables will help to maintain its nutritional value.

Eating fruits or vegetables close to when they were first picked is also a good idea, that way the nutrients do not have a chance to breakdown naturally.

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