A report published online in Hypertension: Journal of the American Heart Association on June 4, 2007 described a finding from the International Study of Macro- and Micro-nutrients and Blood Pressure (INTERMAP) that individuals who consume greater amounts of omega-3 fatty polyunsaturated fatty acids have lower blood pressure than those who consume less.
INTERMAP is a study of lifestyle factors, including diet, and their effect on blood pressure in 4,680 men and women aged 40 to 59 living in Japan, China, the United States, and the UK. Blood pressure was measured and dietary recall questionnaires were completed by the participants on four occasions. Dietary data was analyzed for levels of omega-3 fatty acids from such foods as fish, nuts, seeds and vegetable oils.
The average daily intake of omega-3 fatty acids was 2 grams. Participants with a high omega-3 fatty acid percentage of their daily calorie intake had an average systolic and diastolic blood pressure reading that was 0.6 mm Hg less than participants whose intake was lower. Previous research has found that a decrease of 2 mm Hg reduces the population-wide average stroke mortality rate by 6 percent and that of coronary heart disease by 4 percent.
Higher omega-3 fatty acid intake among the 2,238 subjects who were not using drugs, supplements, or a special diet for hypertension, heart disease, or diabetes was associated with a 1.0 mm Hg reduction in systolic and diastolic blood pressure. For those in this group who did not have hypertension, greater intake was associated with a 0.9 mm Hg average systolic and diastolic reduction.
"Foods with omega-3 PFA had more of an effect in people who were not already taking medication and had not yet developed high blood pressure," stated lead author Hirotsugu Ueshima, MD of Shiga University of Medical Science in Japan.
"With blood pressure, every millimeter counts. The effect of each nutrient is apparently small but independent, so together they can add up to a substantial impact on blood pressure. If you can reduce blood pressure a few millimeters from eating less salt, losing a few pounds, avoiding heavy drinking, eating more vegetables, whole grains and fruits (for their fiber, minerals, vegetable protein and other nutrients) and getting more omega-3 fatty acids, then you've made a big difference."?Related Health Concern: High blood pressure
High blood pressure (sometimes called hypertension) has been nicknamed the silent epidemic because of its far-reaching consequences. Today, nearly one of every three American adults (65 million people) has high blood pressure. In 2002, high blood pressure was implicated in almost 50,000 deaths. It is the 13th largest cause of death in the United States (American Heart Association 2005). Amazingly, studies based on the well-known Framingham Heart Study have estimated that a 55-year-old person who has normal blood pressure has a 90-percent lifetime risk of getting high blood pressure (Vasan RS et al 2002). High blood pressure has been associated with damage to blood vessels in the eyes, heart, brain, and kidneys (Wong ND et al 2005).
Omega-3 fatty acids are essential fatty acids, which means the body needs these substances but is unable to manufacture them. They must come from food, such as cold-water fish or flaxseed. Studies that have looked at the incidence of high blood pressure and omega-3 fatty acids in large populations suggest that diets high in omega-3 fatty acids or dietary supplementation with omega-3 fatty acids can reduce blood pressure (Hirafuji M et al 2003). It appears that omega-3 fatty acids have a direct widening effect on blood vessels (Din JN et al 2004).
Related Products and Information