Phytochemicals

Overview

Phytochemicals are defined as non-nutritive (i.e. non-energy-providing) chemicals found in plants. Scientists have only isolated a few of these in the laboratory, but it is estimated that there are more than a thousand phytochemicals available in our food supply.

You’re probably familiar with some of them, including:

• Resveratrol in grapes/grape skins
• Isoflavones in soy
• Lycopene in tomatoes
• Lutein in spinach
• Naringenin in grapefruit.

Importance

Phytochemicals can help the body ward off disease through various mechanisms. For example:

• Many of them function as antioxidants, helping to scavenge free radicals. The oxidative damage from free radicals can exacerbate the progression of cancer and heart disease. An example of this would be carotenoids in yams, which function as antioxidants.
• Phytochemicals may also influence hormonal function. An example of this would be the isoflavones found in soy and lignans in flax that can mimic estrogen in the body. There are also enzymes in the liver that can make estrogen less effective. These enzymes can be up-regulated by indoles, a phytochemical found in cruciferous vegetables.
• Phytochemicals such as capsaicin, which makes peppers spicy, may help protect DNA from carcinogens.
• Have you ever heard that garlic is anti-bacterial? That is due to allicin, a phytochemical found in garlic. Many other phytonutrients have antibacterial and antiviral abilities. For example, anthocyanins (red, purple, and/or blue plant pigments) found in many fruits can actually prevent the adhesion of pathogens to cell walls. And the proanthocyanidins found in cranberries can prevent the adhesion of pathogens to cell walls, potentially decreasing the incidence of urinary tract infections.

Food Sources

Phytochemicals are found throughout the rainbow of fruits and vegetables.

Deficiencies

Because phytochemicals are not essential to survival, you can get by without them. However, a lack of phytochemicals may mean an overall lack of nutrients, which could put you at greater risk of disease and illness.

On the other hand, phytochemicals can make you healthier and stronger. They will help you heal and recover faster, and look and feel better.

If you’re not feeling like your optimal, healthy self, eating a greater variety across the rainbow of fruits and vegetables can help significantly.

Excess/Toxicity

The more plant foods you consume, the better.

However, eating a surplus of a specific food or phytochemical can potentially have adverse side effects. Example: antioxidants have received “superfood” status lately, but getting carried away and “overdosing” on antioxidants could result in oxidative stress.

A megadose is more likely to occur if taking the phytochemicals in supplement form (pills, juices, powders, etc.). Eat whole plant foods and you shouldn’t have a problem.

Recipe

For recipes rich in phytochemicals, check out any of the fruit and vegetable entries within the Encyclopedia of Food.

Free Recipe Book

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Related Foods

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  Antioxidants
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