Foods That Fight Aging

“We need oxygen to live, but high concentrations of it are toxic to living things,” writes integrative physician Andrew Weil, MD, in his book, Healthy Aging. “Oxygen itself is caustic and destructive; you can see that in the oxidation, or rusting, of iron, when it turns a solid metal into a flaky, corroded material.”

Oxidation creates unstable free radicals, which attack neighboring molecules in a chain reaction that damages cell membranes, DNA, proteins, and other vital elements in the body. Oxygen is just one of many agents that strip electrons from organic molecules, upon which all living things depend. “Free radicals come from the environment, smoking, and various toxins we ingest, including medications,” says Marcia Zimmerman, MEd, CN. “However, most are produced within your own cells as a normal byproduct of converting food into energy.”

“A good case can be made that health depends on a balance between oxidative stress and antioxidant defenses,” adds Dr. Weil. Although our bodies are equipped with such protective defense mechanisms, they’re also bombarded by free radicals from the environment. “Senescence and the appearance of age-related diseases represent the inability of antioxidant defenses to cope with oxidative stress over time,” he explains. However, “If antioxidant defenses are strong, long life without disease should be possible.”

Plant Protection

“The most practical step we can take to defend ourselves against the ravages of oxidative stress is to eat more plants,” Dr. Weil says. One reason the Mediterranean diet is considered so healthy is its “high intake of plant-based antioxidants,” Australian researchers find.

“Amazing plant chemicals have cancer preventive and gene restorative properties,” says Zimmerman. “Moreover, they modify genetic expression and improve cellular metabolism, thus slowing aging and alleviating aging conditions.”

Whether fresh or processed, grown locally or shipped across country, organic fruits and vegetables tend to have higher levels of antioxidants than their conventional counterparts. Research shows significant differences in antioxidant levels of organic produce, compared to crops produced conventionally.

Some Documented Benefits

The Age-Related Eye Disease Study (AREDS) demonstrates one of the important ways antioxidants fight aging. This research found that high-dose antioxidant supplementation—specifically vitamins C and E, beta carotene, and zinc—delayed the progression of age-related macular degeneration. Strong clinical evidence suggests that antioxidants also fight prostate cancer and respiratory infections. Investigators at the Cooper Institute in Dallas find that taking a multivitamin with antioxidants lowers LDL (bad) cholesterol and homocysteine oxidation, while raising blood levels of important nutrients. Though more research is needed, antioxidants offer promise for protection against Alzheimer’s and Parkinson’s diseases.

Antioxidant benefits aren’t limited to aging, either. A new study at Queen’s University Belfast shows that pregnant women at risk for pre-eclampsia who took antioxidant vitamins C and E significantly lowered their risk. Oxidative stress may be at least partially to blame for pre-eclampsia, a serious condition for mothers and their unborn babies.

5 Kinds of Antioxidants

Phytonutrients, as antioxidant plant chemicals are known, give fruits and vegetables their bright colors—and their protective benefits. While they work together against oxidative stress, these dietary antioxidants fall into five different groups, often based on color.

Carotenoids are found in yellow, orange, and red plants, including apricots, carrots, grapefruit, kiwi, mangos, nectarines, pumpkin, spinach, tomatoes, and some spices (including cayenne and turmeric). With more than 600 carotenoids identified, this family of antioxidants is fat soluble, transported through the body on cholesterol and other fats. “Thus they are uniquely situated to prevent oxidation of lipoproteins, a major factor in atherogenesis [development of abnormal deposits of fat in the arteries],” explains Zimmerman.

Alpha, beta, and gamma carotenes are converted to vitamin A in the body. Good thing, too, since these carotenoids are anti-inflammatory, able to modulate cell growth and immune defenders, and offer protection to the brain and nervous system. Other important carotenoids?

• Astaxanthin, found in phytoplankton and sea creatures that consume these one-celled marine plants, offers anticancer benefits, while supporting immunity and helping to protect vision.
• Lycopene, most available in cooked tomatoes, is linked to reduced cancer risk (particularly prostate) and lower incidence of coronary artery disease. It also protects against sun-related skin damage and age-related vision loss.
• Lutein, the primary carotenoid in the retina, is found in leafy greens and peas and fights macular degeneration.
• Zeaxanthin (important to photoreceptors in the retina) protects vision and is available in leafy greens, marigolds, and orange bell peppers.

“You want to get as many different kinds of carotenoids as possible into your diet by eating a great variety of fruits and vegetables in the red-orange-yellow portion of the color spectrum,” advises Dr. Weil.

Sulfur compounds are found in green and white produce. Calcium D-glucarate, cysteine, isothiocyanates, indoles, sulforaphane, and the mineral selenium in the cabbage, garlic, onion, and mustard families activate protective phase 2 enzymes useful in detoxification. Several clinical studies show that cysteine lowers the ratio of fat-to-lean body mass as well as levels of certain cancer-causing agents, while improving the functions of the immune system and skeletal muscles.

Harvard research suggests that indoles in the cabbage family inhibit several cancers, and Scottish studies find that indoles and isothiocyanates protect against DNA damage and stimulate cancer cell death. Sulforaphane in cabbage family vegetables blocks the Cox-2 enzyme that triggers inflammation and pain.

Herbalist James A. Duke, PhD, calls garlic “our premier plant for virtually any heart or circulatory condition.” Besides helping to lower blood pressure and cholesterol, “it markedly impedes LDL oxidation into artery-clogging atherosclerotic plaque.” Garlic also fights cancer, particularly in the gastrointestinal system, and supports the body’s immune defenses, doubling the activity of natural killer cells in the bloodstream.

Phenols and vitamin C are found in black, blue, magenta, and purple plants, including the apple, berry, and grape families; veggies like beets and unpeeled eggplant; and the beverages tea and wine. This group of plant foods includes a number of important phytonutrients: anthocyanidins, flavonoids, polyphenols, and resveratrol. Research suggests that anthocyanidins lower blood pressure, inhibit the spread of cancer, improve vision, and protect against liver damage and ultraviolet radiation, while fighting inflammation, microbial activity, and oxidation. Flavonoids protect against cardiovascular disease and several cancers, and some (like catechins in green tea) support weight loss.

Antioxidant vitamin C fights cancer and cataracts while preventing oxidation of LDL cholesterol. Because C is water soluble and easily destroyed by heat, make sure it’s in your daily multiple. “Natural vitamin C is much more than ascorbic acid,” says Zimmerman, “and to get the full benefit of this vitamin, the entire complex should be taken. This ensures effectiveness with much lower doses—and fewer side effects such as gastrointestinal irritation.”

Vitamin E and its tocopherols and tocotrienols, as well as phytoestrogens, plant sterols, and saponins, are found in tan and brown foods (grains, legumes, and nuts). Because processing (roasting nuts, for example) destroys these nutrients, supplementation is useful.

Research shows that E reduces the oxidation of LDL cholesterol, protecting against heart disease and stroke. Vitamin E also improves insulin response in older individuals and those with diabetes, while boosting glutathione (an antioxidant detoxifying agent), reducing inflammation, and enhancing the body’s immune response.

Phytoestrogens are important in balancing hormones and fighting cancer while also lowering cholesterol. Lignans from seeds appear to help inhibit bone density loss among older women.

Mitochondrial antioxidants (CoQ10, alpha lipoic acid, and L-carnitine) protect against oxidative damage at the cellular level, the primary cause of aging and age-related conditions. Essential to life, CoQ10 is created in the body—but only if 12 other nutrients are available. Statin drugs, increasingly prescribed to lower cholesterol, deplete the body’s stores of this antioxidant, and levels naturally decline with age. CoQ10 supports heart function, protects the brain and DNA from oxidative damage, stabilizes vitamin E, prevents thyroid problems, and may fight cancer.

Lipoic acid also protects DNA and helps improve carbohydrate metabolism. Carnitine moves fatty acids across cell membranes and supports brain, heart, and nerve functions. These three mitochondrial antioxidants are most effective combined in supplement form.

A Balanced Approach

“Antioxidants may protect against the onset of disease and damage progression,” says Jeffrey Blumberg, PhD, who directs the Antioxidants Research Lab at Tufts Nutrition Research Center on Aging, “but they can’t repair damage that has already happened.” In addition, some experts warn against high levels of antioxidants during cancer treatment, since they may reduce the effectiveness of chemotherapy and radiation treatments.

Dr. Blumberg cautions that overempha-sizing antioxidant benefits may give people a false sense of security. For example, eating a handful of nuts or a bowl of blueberries every day won’t make up for a poor diet. Much like wise investing, healthy eating must be diversified, so enjoy a wide variety of brightly colored plants for the best mix of nutrients, and consider supplements for specific needs.