Omega-3 is an essential fatty acid that is deficient in the diets of many Americans. In the late 1970s, scientists learned that the native Inuits in Greenland, who consumed a diet very high in omega-3 fatty acids, had surprisingly low rates of heart attacks. Since that time, more than 4,500 studies have been conducted in an attempt to understand the beneficial roles that the omega-3 fatty acids play in human metabolism and health. Structurally, omega-3 contains 3 double bonds, which makes it a polyunsaturated fatty acid. This also makes omega-3 very susceptible to becoming rancid. Food processors remove it from food products in order to lengthen shelf life. Marine plants such as plankton are the primary source of omega-3 fatty acids in the food chain. Fish and other aquatic animals that feed on plankton incorporate the omega-3 fatty acids into their tissues. The richest land source of omega-3 is the oil that is commercially expelled from flaxseeds.
Body weight is one of the most basic issues of human life. Self-esteem, acceptance among peers– and perhaps lifelong success or failure—are, unfortunately, all tied to our physical appearance. Medically speaking, not all overweight people are obese. Obesity is defined as weight that exceeds 15 percent of normal weight for height and body type. “Morbid” obesity exceeds 20 percent of optimum weight. An obese or overweight person is at high risk for a number of serious health problems, including heart disease, high blood pressure, stroke, varicose veins, dementia, psychological stress, depression, osteoarthritis, high cholesterol, and diabetes. The detrimental health effects of obesity are more than just a matter of weighing too much. Body composition–the amount of fat in the body compared to the amount of lean muscle–is also important. Body mass index (BMI) is associated with overall mortality.
The medical name for high blood pressure is hypertension. High blood pressure is created when the heart beats, propelling blood throughout the body. Blood pressure occurs in two distinct phases, corresponding to the contraction and relaxation of the heart muscle. When the heart contracts, it ejects a certain volume of blood out from its right side into the body’s largest artery, the aorta. This initial thrust causes “systolic” blood pressure, which is the upper number of your blood pressure reading. As the heart relaxes, the blood presses against the walls of the arteries as it circulates, causing “diastolic” blood pressure which is the lower number in your reading. Systolic blood pressure is a measure of the heart’s blood output, while diastolic is determined by the resistance of arteries in the extremities to the flow of blood.
The objective of a recent study published in the journal Nutrition was to investigate whether omega-3 consumption for 8 weeks could improve blood pressure and lose weight. The researchers recruited 324 overweight subjects 20-40 years old and were randomized to one of four energy-restricted diets. Body weight, diastolic blood pressure, systolic blood pressure, and docosahexaenoic acid (DHA) in erythrocyte membrane were measured at baseline and at the end of the study. The results were participants lost between 7 to 11 pounds and there was a decrease in systolic blood pressure and a decrease in diastolic blood pressure. In conclusion the researchers noted that salmon consumption three times a week can decrease diastolic blood pressure similar to that of fish oil capsules which were taken every day in overweight adults.1
1 Ramel A, Martinez JA, Kiely M, et al. Moderate consumption of fatty fish reduces diastolic blood pressure in overweight and obese European young adults during energy restriction. Nutrition. 2010;26(2):168-74.