Ask Tufts Experts: Antioxidant Vitamins; Genetically Engineered Food

I see lots of ads and Web pages touting the benefits of antioxidant vitamins. Should I be taking them?

Alice H. Lichtenstein, DSc, director of the Cardiovascular Nutrition Laboratory at the Human Nutrition Research Center on Aging and executive editor of this newsletter, answers: “Antioxidants neutralize free radicals, molecules in need of an electron which roam the body potentially causing damage by taking electrons from other molecules. Many detrimental effects of aging and causes of disease have been attributed to this oxidative damage. The body makes its own antioxidants, but there are compounds with antioxidant properties in plant foods.

“Some phytochemicals have antioxidant properties, but the bulk of the research on antioxidants has been on vitamins with antioxidant properties, namely vitamin C, vitamin E, and beta-carotene, a precursor to vitamin A. If you put LDL particles with low and high levels of vitamin E in a test tube and add a prooxidant into the system, the LDL with high levels of vitamin E will be more resistant to oxidation. But, unfortunately, it doesn’t appear to work quite that way in our bodies. Studies have found just taking vitamin E, vitamin D, or beta-carotene supplements did not result in any measurable benefit, and in some cases high doses of antioxidant vitamins were associated with adverse effects.

“High levels of supplemental beta-carotene, for example, actually increased risk for lung cancer in vulnerable individuals such as smokers. Very high intake of supplemental vitamin A has been associated with elevated risk for bone fracture in older women.

“Beyond supplements, eating vitamin- and phytochemical-rich plant foods is important for many reasons. Eating more fruits, vegetables, nuts, seeds, legumes, and whole grains in place of sugary, salty, and refined carbohydrate foods and processed meats leads to a healthy dietary pattern and positive health outcomes. Foods that are naturally high in vitamins, minerals, and phytochemicals also tend to be rich in fiber and unsaturated fats, low in saturated fat and refined carbohydrates, and have little added sugars and salt. That’s why it’s important to focus on overall dietary pattern, not individual foods, nutrients, or phytochemicals.”

What is your experts’ take on genetically modified foods? Should I try to avoid them?

Timothy Griffin, PhD, an associate professor and director of the Agriculture, Food and Environment program at the Friedman School of Nutrition Science and Policy, answers: “Genetic engineering (GE) is the process of modifying an organism’s genes to change a characteristic of that organism. The most common use of this process is to make crops insect resistant to cut down on the use of pesticides. Some people are concerned these modified products may be bad for human health, animals, or the environment.

“I learned a lot about this issue as part of an independent national committee that spent two years reviewing the evidence summarized in our 585-page report on genetically engineered crops. Today—about 20 years into the production of GE corn, soybean, and cotton crops—one of the biggest impacts we found on human health and the environment was positive: there has been a large reduction in the amount of highly toxic chemicals being used to control insects. In contrast to public perception, the committee found no unique health or environmental risks from GE crops. But we should continue to be vigilant with continued research.

“Some apples, corn, eggplant, papaya, pineapple, potatoes, and canola plants and sugar beets are genetically engineered. However, many other crops do not currently have genetically modified versions. Except for products where the first ingredient is meat, poultry, or eggs, the FDA now requires that genetically engineered ingredients be clearly labelled with a symbol that says ‘bioengineered.’ Oils and sugar made from GE crops do not need the label. This is because genes are blueprints for building proteins, and there are no GE proteins or genetic material in oils or sugars. For consumers who wish to avoid genetically engineered crops, it may help to know that crops certified as organic in the U.S. cannot use GE technology.”

The post Ask Tufts Experts: Antioxidant Vitamins; Genetically Engineered Food appeared first on University Health News.

Read Original Article: Ask Tufts Experts: Antioxidant Vitamins; Genetically Engineered Food »