Dietary fiber, also referred to as roughage or bulk, is the part of a plant that cannot be digested or absorbed by the body. Adding fiber to the diet is thought to help keep the bowels regular and possibly treat or prevent certain diseases. Dietary fiber is found in grains, fruits and vegetables. There is no fiber in animal products such as meat, fish, eggs or dairy products. Soluble fiber can be found in foods such as oat bran, apples, citrus, pears, peas, beans, potatoes, seeds, oranges, grapefruit and psyllium (a plant product used in common over-the-counter bulk laxative and fiber supplement products such as Metamucil). Soluble fiber is dissolved in water and forms a jelly-like bulk inside the small intestine, which may help to lower cholesterol and reduce blood sugar.
In a new study, researchers assigned 22 women of normal body weight to eat five different chocolate crisp bars in random order. Four of the bars contained 10 grams of one of the following fibers: oligofructose, inulin, soluble corn fiber or resistant wheat starch. The fifth bar contained no added fiber and was used as a control. Each participant received a bar at dinner and then a bar of the same fiber type in the morning. Participants were randomly assigned each fiber type and switched treatments until all participants had been given all five bars. Hunger and fullness feelings were evaluated as the main outcome measures.
The researchers found that participants reported similar feelings of hunger and fullness while on all five bar types. All fiber types were well-tolerated; however, gastrointestinal symptoms were more common for the oligofructose bar.
The authors concluded that adding fiber to chocolate bars may not reduce hunger or alter food intake in the short term. Larger-scale, well-designed clinical trials are needed to confirm these findings.
Along with dietary fiber, whey protein has also been studied for its potential effects on hunger. As a source of high nutritional quality protein, it has 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 that may suppress appetite, please visit Natural Standard's Comparative Effectiveness Database.
For more information about a high fiber diet, please visit Natural Standard's Health & Wellness Database.