Food and technology in the balance.

Humans evolved with their fruit-and-vegetable-heavy diets from primate origins for over 2.5 million years. Only in the last 10,000 years--an evolutionary eye blink--has the human diet changed drastically from these fibrous, roughage-heavy foods. Because our species is capable of manipulating its environment as none other on the planet, we eventually altered our diets severely and unnaturally, causing certain health problems. Genetically, we are not much different from our ancient ancestors, but our diets are. The ability to mill and cultivate cereal grains caused the major substitution of fresh fruits and vegetables with flour-based food. Much less densely packed with essential vitamins and minerals, grains are also completely void of phytochemicals. These plant-based nutrients are powerful antioxidants, and their role in our health--from cancer prevention to faster recovery from workouts--is widely recognized today.

The fact that up to a quarter of adults worldwide cannot properly digest animal milk is indicative of how far we've drifted from our natural diet. But our easy manipulation of what we consume doesn't stop there. We severely process many of our foods for convenience, and the result is a dangerously increased intake of preservatives, flavor enhancers such as MSG, hydrogenated vegetable oils, artificial colors, and corn syrup. Diseases of affluence like obesity, diabetes, high blood pressure, and heart disease are the result.

You can minimize your consumption of processed foods and refined sugars by returning to the diet of our ancestors. Several years ago, the United States Department of Agriculture (USDA) published the 20 best sources of cancer-preventing antioxidants, and it's no surprise that they are all fresh fruits, vegetables, and legumes: blueberries, cranberries, blackberries, prunes, raspberries, strawberries, apples, cherries, plums, red beans, black beans, pecans, artichokes, and russet potatoes were among the highest. Aim for between three and five servings each of fresh fruits and vegetables a day.

While phytonutrients aren't essential by traditional definitions, the USDA Agricultural Research Service (ARS) reports that they appear to reduce the risks of many diseases associated with aging. On the ARS Web site, the government writes, "The isoflavones in soy products may reduce the risk of heart disease, osteoporosis, and several types of cancer. Certain flavonoids in blueberries may actually reverse nerve cell aging. And a wide array of compounds in fruits and vegetables may protect cell components against oxidative damage ..."

Ironically, it is our ability to manipulate our food supply that is now increasing the nutritional value of many fruits and vegetables. The ARS says, "Projects have sprouted up to screen germplasm for specific phytonutrients or to find ways to increase or preserve them in cultivated varieties." We can now produce tomatoes with between three and 10 times more lycopene than normal. ARS researchers are examining soil differences and other factors to explain differences in cantaloupes grown at their Subtropical Agricultural Research Center in Weslaco, TX. The various fruit crops differ in beta carotene levels by some 500%. Researchers at the ARS Vegetable Research Unit in Charleston, SC and at Johns Hopkins University in MD have bred broccoli with 30 times the supposed anti-cancer phytochemical glucoraphanin. Even studies on vegetable storage have found ways to preserve phytonutrient levels. Onions that have been in cold storage up to 90 days show more anti-platelet activity. This can reduce cardiovascular disease risk by interfering with the clumping of blood platelets.

Today's fresh whole foods, then, often taste better, contain more nutrients, enjoy better crop yields and resist disease more effectively than in the past. Ever-advancing science and technology, while sometimes compromising our nation's health, have also provided us with vast quantities of useful information and made more of these important foods widely available.

(Runner's World Performance Nutrition for Runners by Matt Fitzgerald, 2006, Rodale Press, pp. 25-38; Phytonutrients Take Center Stage, Agricultural Magazine, Dec. 1999, www.ars.usda.gov/is/AR/archive/dec99/stage1299.htm; www.ars.usda.gov/main/main.htm)