When we were growing up our moms told us to eat our fruits and vegetables. We would have to sit at the table, with no chance of leaving to play, until our plate was devoid of these strange foodstuffs. Oh what worse torture could a mother bestow upon us than this! But now that we’re older and wiser (hopefully!), we understand that mom loved us and her intentions were pure. She was just looking out for our health.
We’ve known for some time now that these colorful plant foods have many attributes beneficial to health. Most are naturally high in vitamins and fiber, and low in sodium, fat and calories. But nutritional science has come a long way since mom’s dinnertime mandates. We now know that plant foods, such as fruits and vegetables, have even greater benefits than mom could have ever realized.
What are they?
Thousands of substances called phytochemicals (“phyto” being Greek for plant), that contribute to health in a variety of ways, have been found in plant foods. Phytochemicals is a catchall term for the vast array of chemical substances found naturally in plants. These substances serve various functions beneficial to plants. They provide a defense against predators, such as viruses and plant-eating insects. Phytochemicals are also pigments that attract insects and animals to facilitate fertilization. Then when plants are consumed by people, their phytochemicals provide health benefits to us. They are also responsible for both the taste and beautiful colors of plant foods. So the next time you’re in the produce section at the grocery store, you can say “look at all those colorful phytochemicals!” (But not too loudly!)
How much does food have?
The quantity of any particular phytochemical found in a food, or many traditional nutrients for that matter, is determined by genetic and environmental factors. Genetically, some varieties of foods naturally have higher amounts than others. Environmental determinants include soil and fertilization methods; sunlight exposure; altitude, climate and temperature; maturity of plant; presence of predators; and storage, processing and preparation methods.
What are the health benefits?
Several methods have been identified by which phytochemicals, also known as phytonutrients, benefit our health and prevent disease. The antioxidant properties moderate damage to cells from oxidation by free radicals. This can help decrease the risk of various cancers, as well as prevent the oxidation of LDL (the “bad”) cholesterol that can lead to heart disease. Some prevent bacteria from sticking to places they shouldn’t (e.g. the bladder, to prevent urinary tract infections – think cranberry juice!), some prevent blood vessels from sticking together reducing the risk of heart attack and stroke, and some reduce inflammation in artery walls helping prevent the buildup of plaque deposits. Other phytochemicals can enhance the body’s ability to detoxify chemicals, slow or stop the growth of cancer cells, and even kill cancer cells. These are only some of the benefits, as new ones are discovered almost daily.
Research has found that phytochemicals differ in the health benefits they provide. Each type of plant food contains differing amounts and types of phytochemicals. And since most are also pigments with very striking colors, eating a “colorful diet” is good advice (the “Rainbow Diet?”). Also, while research has shown evidence of health benefits from food sources, phytochemical supplements have not shown the same benefits. Optimal but safe intakes have yet to be determined. There is some research evidence indicating that taking supplements of individual phytochemicals may actually be deleterious to health. It is believed that foods have the correct balance of phytochemicals, and that they act synergistically to provide their benefits. This is another reason why you should eat a variety of different plant foods to reap optimum health benefits. And don’t forget to eat the skins, as this is where the highest concentration of phytochemicals is often found!
There is some evidence linking herb usage to disease prevention, because of their concentrated stores of phytochemicals. The most common herbs used in cooking – parsley, sage, rosemary, thyme, cilantro, oregano, basil, mint and all their cousins – could be a treasure trove of health benefits. So if you enjoy cooking, try spicing up your dishes with these rather than adding salt or fat. The table below provides a glimpse of some of the health benefits of herbs.
Nutrition recommendations can sometimes seem overly complex and confusing. But if I were able to give just one piece of nutritional advice, it would be to eat lots of different plant foods flavored with spices. Your odds of being healthy would be greatly increased and mom would definitely approve!