Phytochemicals are naturally occurring chemical compounds in plants. While you may not be as familiar with phytochemicals, they provide the body with biologically significant chemicals to potentially reduce the risk of chronic disease, cancer, heart disease and stroke, among other benefits.
One example we should all be familiar with is the phytochemical antioxidants, which is famous for its supposed anti-aging properties and found in foods such as blueberries. It is important to note, however, that FDA studies have resulted in inconclusive results with respect to the medical benefits of consuming phytochemicals.
Believe it or not, humans have been prescribing the use of phytochemicals for millennia. Modern day aspirin has its roots in salicin, a willow tree extract. Interestingly, Hippocrates may have prescribed willow tree leaves to treat headache without knowing exactly why they work.
While scientists estimate that there may be over 10,000 different phytochemicals, thankfully they can be grouped into a few different types: Polyphenols, flavinoids, antioxidants, carotenoids and allyl sulfides, according to the American Cancer Society.
Some of these groups overlap, as an antioxidant is simply a chemical compound that delays cell oxidation (i.e., aging). Here is a sample of some prevalent phytochemicals and various fruits and vegetables containing high levels of the specified phytochemical:
- Beta-carotine: dark, leafy greens and red, yellow and orange fruits and vegetables
- Lycopene: tomatoes, grapefruit, watermelon, guava and carrots
- Lutein: spinach, romaine lettuce, eggs, rep pepper and pumpkin
- Phytosterols: almonds, cashews, peanuts, sesame seeds, soybeans, buck wheat and wheat germ
- Flavonols: Red and yellow onions, ginger, tea, grapes, citrus fruits and red turnips
Check out the Wikipedia entry List of Phytochemicals in Food for many other food listings and a more detailed breakdown of the phytochemical categories.
Regardless of a lack of hard scientific evidence, consuming a varied, colorful diet heavy in fresh fruit and vegetables with provide you with a variety of phytochemicals and is a best practice that certainly all nutritionists and dietitians would recommend.