Biotech Flax With Increased Omega-3 Levels Could Improve Human Health

Enhanced flax seeds could bring the benefits of fish oil to vegetable-based cooking oils. A team of researchers led by Ernst Heinz from the University of Hamburg in Germany has successfully developed a genetically enhanced flax (or linseed) plant that has boosted levels of healthful long chain polyunsaturated omega-3 and omega-6 fatty acids that are believed to reduce the risk of heart disease, cancer, Alzheimer's and many other diseases. As reported in the October issue of The Plant Cell, Heinz and his team inserted genes from algae and moss into flax plants to produce nutritionally significant amounts (about 5 percent) of omega-3 and omega-6 fatty acids. Often referred to as "healthy" fats, omega-3 and omega-6 fatty acids are essential building blocks the body needs for tissue growth and normal functioning — especially the eyes and the brain. Omega-6 fatty acids are readily available from a variety of foods (including almost all vegetable oils), but, at present, the best dietary source of omega-3 fatty acids is coldwater fish such as salmon, mackerel and tuna. Unfortunately, many people don't consume enough fish. And pregnant women and young children are often advised to avoid eating certain kinds of fish that have traces of mercury and PCB's, even though these elements are at very low levels and pose minimal risks. Further, global fish stocks are in decline. "Our research should lead to the creation of a sustainable source of these very long chain polyunsaturated fatty acids that are required for human nutrition," says Heinz. "At present the only reliable source is fatty fish, but these marine resources are declining dramatically." By the mid 1990s, 70 percent of the wild ocean fisheries were already so heavily exploited that reproduction couldn't keep up or could just barely keep up with demand. Heinz himself eats fish weekly to obtain the health benefits. And he counts himself among those who could benefit even more by eating genetically enhanced flax plants. Essential fats in the diet Despite the well-publicized increase in obesity around the world, eliminating fat from human diets isn't healthy. In fact, you wouldn't live long with out it. Instead, it is commonly suggested that about 30 percent of our overall calorie intake come from fat. There are three basic categories of fat: saturated, polyunsaturated and monounsaturated. Saturated fats typically come from fatty meats and whole-fat dairy products. The unsaturated fats typically come primarily from vegetable oils, nuts and fish. "We really need some of each of these three fats," says Gail Frank, professor of nutrition at California State University–Long Beach. Frank, who is a spokesperson for the American Dietetic Association, specializes in the study of the relationship of food and nutrition to disease. "Ideally, a person ought to get only about 8 percent of their daily fat intake from saturated fats, not more than about 10 percent from polyunsaturated fats and about 12 percent from monounsaturated fats." It is within the polyunsaturated fat category that we find omega-3 and omega-6 fatty acids. The human body cannot manufacture these fatty acids; the only way to get them is through the foods we eat. Along with the amount of these fats in the human diet, the ratio of them is also important. Ideally, it would be around four (omega-6) to one (omega-3). Because omega-6 fatty acids are readily available in a multitude of vegetable oils, this ratio is commonly in the range of 10 to 20 (omega-6) to one (omega-3). "People first began suspecting that omega-3 fatty acids might play a role in disease prevention when early studies revealed that the Inuit people — whose diet was very high in fat — had a much lower incidence of heart disease than one might otherwise suspect," says Frank. Since then, the list of diseases that omega-3 fatty acids might help prevent has grown dramatically. Although the results are not yet conclusive, preliminary studies indicate that omega-3 fatty acids may help prevent or have a positive influence on rheumatoid arthritis, asthma, lupus, kidney disease, macular degeneration and depression. While omega-3 fatty acids are present in nuts, flax, soybean oils, and a few other foods, currently fish remains the number one source of these essential nutrients. That's why nutritionists and health watchdog organizations alike recommend including fish as a regular part of one's diet. Prominent organizations that recommend the regular consumption of fish include the American Diabetes Association and the American Heart Association. Healthier oils and meat The most direct route for Heinz's research to improve human nutrition would be through the development of cooking oils from genetically enhanced oilseeds. Using cooking oils with a healthier fat profile — and a properly balanced ratio of omega-3 and omega-6 fatty acids — would definitely be a step in the right direction. And such enhanced oilseeds could also be used to produce nutritional supplements, although nutrition experts like Frank say the benefits of supplements are generally unproven and that eating a balanced diet is still the best way to meet nutritional requirements. But for Cindy Moore, director of nutrition therapy for the Cleveland Clinic Foundation, these applications would simply be the very small tip of a very large iceberg of possibilities. "People often overlook the fact that plants and plant seeds with enhanced levels of omega-3 fatty acids could also be used as animal feed," says Moore, who is also a spokesperson for the American Dietetic Association. "There is a trickle-down effect. The omega-3 fatty acids that are in the food we give our cattle, pigs and chickens, ends up in the meat, milk and eggs they produce." So in effect, Heinz's research may one day result in a meal of bacon and eggs that has as much omega-3 as a serving of Atlantic salmon. "What's really exciting about this research breakthrough is that it opens the door to reducing the risk for a number of chronic diseases with a minimum of behavior modification," says Moore, who notes that history has proven it can be extremely challenging to convince people to alter their diets. "One of the greatest benefits of biotechnology is that it allows us to introduce these benefits transparently. Any time we can improve the nutritional profile of the foods people eat without having to convince them to change their habits — that's a good thing. It's a real winner." "source":[ http://www.whybiotech.com/index.asp?id=4744].

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