Flaxseed fiber, consumed as a supplement or drink, may reduce appetite, according to a recent study.
Flaxseed and its derivative flaxseed oil/linseed oil are rich sources of the essential fatty acid alpha-linolenic acid, which is a biologic precursor to omega-3 fatty acids such as eicosapentaenoic acid. Although omega-3 fatty acids have been associated with improved cardiovascular outcomes, evidence from human trials is mixed regarding the efficacy of flaxseed products for coronary artery disease or high cholesterol.
As a source of fiber mucilage, oral flaxseed (not flaxseed oil) may possess laxative properties, although only one human trial has been conducted for this indication. In large doses, or when taken with inadequate water, flaxseed may precipitate bowel obstruction via a mass effect. The effects of flaxseed on blood glucose levels are not clear, although hyperglycemic effects have been reported in one case series. There is currently limited research on the effects of flaxseed flour in obese patients.
In a new study, researchers conducted two studies to evaluate the effects of a flaxseed drink and flaxseed supplement on appetite.
After an overnight fast, 24 individuals were randomly assigned to receive a flaxseed drink containing 2.5 grams of soluble fiber or placebo. A second group of 20 individuals were randomly assigned to receive a flaxseed drink or flaxseed supplement, both containing 2.5 grams of soluble fiber. Appetite was measured using visual analog scales.
The researchers found that the flaxseed drink increased the feeling of fullness and significantly reduced the amount of food eaten following the drink when compared to the control group. Similar findings were found when the flaxseed drink was compared to the supplement.
The authors concluded that a flaxseed drink or supplement may increase fullness and reduce appetite. However, larger-scale, well-designed studies are necessary to confirm these findings.
Several other integrative therapies have been studied for their potential effects on appetite. Early research suggests that Korean pine nut oil decreases food intake and feelings of hunger. Additional long-term research in this area is needed.
As a source of high nutritional quality protein, whey protein has also been found to reduce short-term food intake and may aid in reducing appetite. Additional studies are required before firm conclusions can be made.
For more information about integrative therapies for weight loss or appetite suppression, please visit Natural Standard's Comparative Effectiveness Database.
For more information about flaxseed, please visit Natural Standard's Foods, Herbs & Supplements Database.
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