I'm willing to bet you probably haven't heard the word 'phytochemicals' before. But you've been eating them your whole life and they are vitally important to your life and well-being. They are one of the keys to real health.

So, what are they? Phytochemicals are biologically active substances in food. They have health enhancing abilities and possibly curative abilities. They number in the hundreds in most plant foods. They are found in fruits, vegetables, legumes and grains.

Phytochemicals work together with nutrients to promote health and prevent disease. When you eat some broccoli or a tomato, you get all of these phytochemicals. So, can't you just take a supplement? You could, but first of all, scientists have isolated only a few of the phytochemicals in foods. But these work best in combination, so taking just one, isolated phytochemical is not anywhere near as effective.

For example, let's look at lycopene. It is found in tomatoes and is an antioxidant. Antioxidants are a large and important subject, but for now, let's just simplify and say that antioxidants help to repair cellular damage.

Scientists did studies and found that tomatoes had a noticeable effect against prostate cancer. They analyzed the tomato and isolated lycopene. Then the scientists did more studies, using lycopene. The effect on prostate cancer was much less. Does this mean that lycopene doesn't work?

No, it means that it works best in combination with all the other phytochemicals in tomatoes, and the nutrients. You don't get that from a chemically identical, but lab-created, lycopene.

Eating a tomato is good for you, of course. But eating all the tomatoes you would need to get what you need from them would be quite a task. So, a whole foods powder that I use, Berry Greens, offers freeze dried tomatoes, in a form that retains the nutrients. And a whole lot of other vegetables and fruits as well. You get all the benefits of eating all those fruits and vegetables, without having to consume all that food.

Most foods have not been analyzed and even those that have been, scientists have only been able to isolate a few of the phytochemicals. Most vegetables have hundreds of phytochemicals, and it's not likely they will all be isolated, analyzed and understood any time soon. We do know now, though, that they do work together to provide real health for us.

Barbara Pfieffer writes about gaining real health on her blog, Real Health. She has resources on what supplements really work, the differences among carbohydrates and other information to bring you to real health.