Phytonutrients are My Friend…
This is a great article on phytonutrients and their health benefits from World’s Healthiest Foods.
Phytonutrients are plants' home security services--think of them as the Plant Police, Fire Department and Coast Guard. As defenders, phytonutrients protect their plant from free radical attack from excess ultraviolet radiation and from predator pests. And phytonutrients do their job with style, providing plants with their sensory characteristics such as their color, flavor and smell.
Unlike us, plants can't move, put on a fan or air conditioning when it gets too hot, or put on sunscreen or sunglasses. But, even more than we, plants are exposed to damaging radiation, toxins, and pollution, and this toxic exposure results in the generation of free radicals within their cells. Free radicals are reactive molecules that can bind and damage proteins, cell membranes and DNA. Since plants can't move away from these insults, nature has provided them with a means of protection: they can make a variety of types of protective compounds--the phytonutrients. Like plants, we're exposed to ultraviolet radiation or pollution, we also generate reactive, free radicals, and although we cannot produce our own phytonutrients, when we consume plants, their phytonutrients also protect us against damage from these free radicals.
Most plants use sunlight as an energy source. Although to the eye sunlight appears as a single, clear, bright force, it is actually made up of many different wavelengths, some of which the plant captures for the generation of energy. Others, however, are wavelengths from which the plant needs protection. Each plant contains literally thousands of different phytonutrients that can act as antioxidants, providing protection from potentially damaging free radicals. Many of these compounds also provide the plants with color, their different colors each reflecting a different variety of protection they provide.
Plants Contain Thousands of Phytonutrients
If a plant was only one color, with no shades or variations in that color, it would only be able to receive and protect against one specific wavelength of light. A plant with several different colors is like a television set with an antenna, and a plant with many different colors is like a television with a satellite dish. Most plants have a satellite dish's worth of colors - even ones that look very green to us when we eat them. Like the primer used beneath a coat of paint, these other colors are simply overshadowed by the primary color that we see.
Some researchers estimate up to 40,000 phytonutrients will someday be fully catalogued and understood. In just the last 30 years, many hundreds of these compounds have been identified and are currently being investigated for their health-promoting qualities. At research organizations like the National Institute of Cancer, and at many universities around the world, different individual phytonutrients are being studied to identify their specific health benefits.
Phytochemicals in Fruit - Anthocyanidins
With over two thousand known plant pigments presently identified, the chemicals that give foods their colors may also translate into vibrant health. Notable among these phytochemical pigments are the bioflavonoids known as anthocyanidins. These are the purple-blue pigments that give fruits such as blueberries, blackberries, raspberries, black currants, and red and purple grapes their unique coloration, and which protect them from the damaging effects of oxidation.
As researchers confirm that metabolites of oxidation, known as free radicals, are at the root of the progression of both chronic diseases (such as arthritis, atherosclerosis, diabetes and cancer) and other signs of aging, such as the loss of skin elasticity and cognitive function, antioxidants are gaining an ever more important place in health promotion. Among the antioxidants, anthocyanidins have been found to have some unique features. They are able to protect cells and tissues from free radical damage in both water-soluble and fat-soluble environments. And, their free radical scavenging capabilities are thought to be more potent than many of the currently well-known vitamin antioxidants; anthocyanidins are estimated to have fifty times the antioxidant activity of both vitamin C and vitamin E.
Phytochemicals in Vegetables - Glucosinolates
Just like our mothers told us, the foods we loved to hate as kids have turned out to be especially healthy for us. Members of the brassica family of vegetables, including broccoli, Brussels sprouts, cabbage, kale and bok choy appear to have significant cancer-preventive properties. Studies have shown that people who consume these vegetables frequently have a lower risk of developing a variety of cancers, including cancers of the colon, stomach and lung.
Phytochemicals in Whole Grains - Ferulic Acid
Diets that feature significant amounts of whole grains have been shown to offer protection against the development of cardiovascular disease and certain types of cancer. While whole grains provide an array of important constituents such as fiber, resistant starches, vitamins and minerals, the whole story of whole grains can't be told without appreciating the important health contribution of the phytochemicals that they contain.
The germ and bran of whole grains such as rice, barley and oats contain a concentrated amount of important phytochemicals that belong to the organic acid family. Included among this family of compounds are caffeic acid, ellagic acid as well as ferulic acid, a phytochemical at the crux of recent research efforts. While whole grains are significant sources of ferulic acid, certain fruits and vegetables such as spinach, parsley, grapes and rhubarb are also known to contain this important compound.
Phytochemicals in Tea - Catechins
While drinking tea is a cultural ritual of community in Asia, it is now becoming a cultural ritual of wellness in the West. This is because green tea consumption has been shown to have many health benefits that researchers believe are related to the phytochemicals that it contains. Of these phytochemicals, the ones receiving the most attention are called the catechins, and include individual compounds called epicatechin, epicatechin gallate, and epigallocatechin gallate. In addition to being an important feature of green tea, catechins are also featured in other plant-based foods such as apples, grapes, raspberries and avocadoes.
In one very large scale study, the catechins in tea have been show to lower risk of stroke by approximately 20% when consumed in plentiful but still customary amounts. One cup of green or black tea in the morning, another in the afternoon, and a third in the evening were shown to provide the 30-50mg amount associated with risk reduction for stroke.
What amount of food phytochemicals is healthy?
Although research is supporting their significant health benefits, phytochemicals are presently considered "non-essential" nutrients. Unlike vitamins and minerals, there are no RDAs or DRIs for them. One reason for the difficulty in setting a level is that there are so many of these phytonutrients that appears to provide health benefits; hundreds are presently being researched for their health-promoting effects. Another reason for the difficulty in setting standards for consumption is that many of these phytonutrients have similar activities. Instead of a lot of one specific compound, it may be more important to have a certain level of a family of compounds, but you can have different amounts of the individual compounds and still get the health-benefit.
Finally, new research is uncovering that many of these phytonutrients act synergistically; that is, they help each other and provide more benefit when taken with other phytonturients than alone. This is a major reason for eating whole foods over taking an individual supplement of beta-carotene or vitamin C. The whole food can contain not only the beta-carotene or vitamin C, but also other phytonutrients that act synergistically to support even more benefit to your health.
The major classes of phytonutrients include:
Organo-sulfurs: example, the glucobrassins found in crucifers and the allyl sulfur compounds in garlic.
Terpenoids: These include the basic terpenoids like limonene found in citrus foods and menthol, as well as the carotenoids (vitamin A precursors), coenzyme Q10, the phytosterols, and the tocopherols and tocotrienols.
Flavonoids: Flavonoids are the plant pigments that give plants their colors, like the deep blue of blueberries, the purple of grapes, the orange of pumpkins, or the red of tomatoes. Flavonoids include the anthocyanidins in blueberries and quercetin found in onions.
Isoflavonoids and lignans: For example, genistein and diadzein found in soy foods, and the lignans in flaxseed and rye.
Organic acids: example, ferulic acid, which is found in whole grains, and the coumarins, which are found in parsely, licorice and citrus fruits.