Phytochemicals are non-nutritive plant chemicals (manufactured by plants, not merely contained in plants) that have protective properties against disease. As non-essential compounds, they are not required to sustain life, but they promote a long healthy life. There are dozens of known phytochemicals, and as they are the “latest thing” in nutritional science, it is likely that we are only scratching the surface of a comprehensive list.
So how to phytochemicals promote health?
- Firstly, they have antioxidant properties–that is, they protect cells against oxidative damage. See Oxidation: Explaining Free Radicals, Cell Damage, and Antioxidants. Known phytochemicals with antioxidant activity include allyl sulfides (found in onions, leeks, garlic), carotenoids (fruits, carrots), flavonoids (fruits, vegetables), polyphenols (tea, grapes).
- Some phytochemicals have hormonal actions. We know, for example, that certain foods like soy and flax have high levels of plant estrogens, which behave in the body similarly to estrogen, and can offset symptoms of menopause.
- Some phytochemicals influence enzymes. Enzymes are substances produced by a living organism that act as a catalysts to bring about specific biochemical reactions. Considering how pracicaly everything that occurs in the human body requires enzymes, the implication that phytochemicals influence enzygmatic processes is enormously important. For example, indoles (found in cabbage) stimulate enxymes that make estrogen less effective, and may reduce risk of breast cancer.
- Saponins, a phytochemicals found in beans, interfere with the replication of cell DNA. This may reduce risk of cancer.
- Many phytochemicals have anti-bacterial properties.
- Some phytochemicals bind physically to cell walls; this aids in preventing the adhesion of pathogens to human cell walls. Proanthocyanidins are phytochemicals found in cranberries, a popular remedy against urinary tract infections.
Phytochemicals are essentially plant chemicals. You get them when you eat plant foods. While mainstream nutritional recommendations are obsessed with nutrients, macro (protein, fat, carbohydrate) and micro (vitamins, minerals, and trace minerals), phytochemicals went ignored until recently. Chemistry is powerful, and small amounts (microscopic) of substances can be the key to health. Phytochemicals, after all, have been implicated as cancer-fighting, disease preventing, cholesterol lowering, house-cleaning compounds that are health promoting, especially when sourced from their whole plant forms.
But supplementing your body with a single phytochemical may not be sufficient. Why not take a pill? Take phytochemicals as a supplement? Plants, like every living thing, have certain properties and (arguably) intelligence that can work in concert with so many plant-sourced co-factors, the complexity of which is entirely unknown to nutritional science. In short, while quantitatively the same, they are not qualitatively the same.
Peoples have been healing and treating disease with plants for millenia, without having to adulterate or synthesize them. The notion that the consumption of plants with certain properties may confer those properties to the consumer is timeless; just as being in an environment will adapt one to certain environmental conditions. This is the greatest argument in favor of eating local and seasonal. The properties needed to adapt to environmental conditions are contained within those plant foods.
The secret to health does not come in a plastic pill bottle; it never did.
Start protecting your health by eating a large variety of plant foods, a variety of colors, preferably in their raw form.
The following list of phytochemicals was sourced from http://www.phytochemicals.info/phytochemicals.php