Dieters who ate omega-3 fatty acids from fish oils or fish had less hunger, lower cholesterol and fats, and managed blood sugar better, three new studies reveal.In an appetite study, researchers theorized that omega-3 fatty acids could help dieters feel satisfied after eating. About 230 overweight or obese participants took a low dose of less than 260 mg of omega-3s or a high dose of more than 1,300 mg of omega-3s per day while on a balanced but low-calorie diet for eight weeks. In the last two weeks of the study, participants ate a test dinner of either low or high amounts of omega-3s while researchers measured sensations of hunger immediately afterward and again two hours later. Those who ate the high-omega-3 meal felt less hungry and more full immediately after and two hours after the meal than those who ate the low-omega-3 meal. Doctors concluded that omega-3s help control feelings of hunger.
In a study of blood fats, about 320 overweight or obese participants aged 20 to 40 ate a balanced low-calorie diet. Two groups ate less than 260 mg of omega-3s per day including lean codfish or placebo oil capsules while two other groups ate more than 1,300mg of omega-3s per day consisting of fatty salmon or fish oil capsules. After eight weeks, researchers discovered that all types of fish and fish oil reduced total cholesterol and overall blood fats, and both salmon and fish oil preserved HDL, the “good” cholesterol.
In a related study using the same group of participants from the blood fats study, researchers found that those who ate omega-3s while dieting had healthier levels of insulin on an empty stomach and were more sensitive to insulin after eight weeks. Insulin helps the body convert blood sugar (glucose) into energy.
Reference: International Journal of Obesity; 2008, Vol. 32, No. 7, 1105-12.