Scientists continue to explore how certain food components have the ability to create feelings of fullness, thus delaying the onset of hunger.



Scientists continue to explore how certain food components have the ability to create feelings of fullness, thus delaying the onset of hunger. This concept is a key factor in the emerging food and beverage category collectively referred to as weight management products. Such goods differ from those described as weight loss products, as their objective is not to help you lose pounds, rather to help you maintain a healthy weight.

However, according to a 2008 consumer study conducted by The NPD Group, Port Washington, N.Y., and commissioned by Dairy Management Inc. (DMI), Rosemont, Ill., 67% of respondents said that feeling full is important to them when trying to lose weight. Thus, foods that help one feel fuller for a longer period of time appeal to both dieters and weight-conscious consumers. 

According to the hot-off-the-presses 2009 IFIC Functional Foods/Food for Health Consumer Trending Survey from the International Food Information Council (IFIC), Washington, D.C., 81% of consumers “somewhat” or “strongly” agree that certain foods contribute to a healthy body weight. Further, 80% say they are aware of this relationship: “protein, found for example in meat, dairy, beans, nuts, soy and some fortified foods and beverages, for weight management and to provide a feeling of fullness.” Of those aware of this relationship, 50% are already consuming such foods and 42% are likely or somewhat likely to consume such protein-based foods for weight management in the future.  

Hormonally challenged

Most consumers know the simple formula for weight management: calories in (eating) equal calories out (burning). Sounds easy, but many are challenged by feelings of hunger at inconvenient times, which can result in making poor food choices, as well as uncontrollable cravings. Controlling appetite by promoting satiety, the feeling of being full, is a valuable approach to weight management.

Believe it or not, feeling full has little to do with the body’s need for nutrition. It is all about gastrointestinal hormones.

Ghrelin is believed to be the primary hunger hormone, with levels increasing before meals and decreasing after meals. In the brain’s hypothalamus, ghrelin binds to receptors related to metabolism, while also binding to receptors in the midbrain that link to reward and pleasurable food associations. Interestingly, lack of sleep can impact appetite and weight gain as a result of ghrelin, as levels increase due to short-sleep duration, thereby increasing appetite.

There are several other hormones recognized with controlling hunger and eating. For example, the peptide cholecystokinin (CCK) helps the digestion of fats and protein in the small intestine. This neurotransmitter connects with CCK receptors in the central nervous system, where it influences reactions such as anxiety and nausea, as well as feelings of satiety and hunger.

Glucagon-like peptide-1 (GLP-1) and peptide YY (PYY) are known for sending a message of fullness to both the brain and stomach. This slows the movement of food in the gut, thereby ensuring maximum digestion of nutrients and decreased appetite.

With increasing interest among food manufacturers to develop foods and beverages that impact appetite-hormone activity, U.K.-based Leatherhead Food Research has developed methodologies for investigation of both satiation (the feeling of fullness immediately following consumption) and satiety (the influence on subsequent feeding events). These can be tailored to the precise needs and target outcomes of the client and range from a simple, rapid assessment of satiation using Visual Analogue Scales (VAS) questionnaires, to the measurement of gut hormones related to appetite following a meal. Depending upon country, results can be used to promote products for appetite control.

In the simple method, subjects are provided with a test food and asked to complete VAS questionnaires on handheld computers at regular intervals over several hours. This method assesses satiation. To assess satiety, the amount of food consumed at the next meal can be measured and analyzed for its nutritional content. For a more comprehensive view of the satiating effects of a food, subjects can be provided with a pre-load food several hours before a standardized lunch and their levels of certain gut hormones, such as ghrelin, PYY and GLP-1, measured over a four-hour period.

Formulating opportunities

Despite the current economic crisis, the weight management market will continue to expand, according to a research report published in April 2009 by Business Insights Ltd., London, entitled Innovation in Weight Management. A surge in regulatory policies surrounding the marketing of weight management foods requires manufacturers to substantiate all associated claims with comprehensive scientific evidence including controlled clinical trials.

According to the report, launches in the global weight management sector increased at a rate of more than 1.8% from 2007 to 2008. Additional data suggests growth in this market to continue through 2010, with new product rollouts increasing annually as a rate of 3.7%

Ingredient suppliers offer an array of ingredients shown to assist with decreasing appetite. Dairy foods, naturally a source of high-quality proteins, which alone have been shown to reduce appetite, are the ideal delivery vehicle for many of these ingredients. This includes concentrated whey proteins, which puts dairy ingredients back into dairy foods.

Dairy foods can be enriched with fiber ingredients, a number of which have been shown to contribute to satiety. For example, a University of Minnesota clinical study comparing the effects of three types of dietary fiber - soluble, insoluble and resistant starch - on people’s satiety response found that natural resistant starches from high-amylose corn enhanced feelings of fullness and satisfaction more than the other types of dietary fiber. Results from the randomized, crossover clinical trial were published in the February 2009 issue of Nutrition Research.

Another option is a proprietary appetite suppressant that is a 100% natural vegetable product based on pine nut oil derived from the nuts of the Korean pine (Pinus koraiensis). This ingredient has been shown to significantly increase the release of the hunger-suppressing hormones, in particular CCK. This was shown twice in randomized, double-blind studies.

The ingredient comes as an oil in triglyceride form and can be applied to a range of food products. It is especially recommended for liquid food products such as milk, yogurt and beverages. Beneficial effects have been demonstrated at a dosage of 3 grams per serving, which easily works into a yogurt or ready-to-drink milkshake formulation.

A patent-protected combination of oat and palm oils has been formulated into a stable emulsion. Its microstructure prevents digestion of the palm oil droplets until relatively deep in the small intestine. Undigested fat arriving in the ileum (the latter part of the small intestine) triggers an “appetite satisfied” signal to the brain.

Single-serve aseptically packaged Silhouette Active from French dairy producer Candia, contains this satiating ingredient. Olivier Cousin, R&D director at Candia, says, “Over half the French population actively monitor their weight, but controlling appetite is not easy. Silhouette Active comes in a convenient carton with optional straw - perfect for on-the-go consumers who want to regulate food intake without interrupting their lifestyles. One carton provides an ideal drink, or the perfect amount to use on a bowl of cereal.”

Lipidsana is another unique dairy-based satiety beverage. This meal replacement milkshake from Germany’s Lipid 4Life GmbH, is fortified with the omega-3 fatty acids docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), and medium chain triglycerides (MCTs) with thermogenic - fat burning - properties called dual lipid oxidation.

“Our milk-based shakes are nutrition products with a special effect - they enhance lipid oxidation and have special health-promoting effects,” says Benedict Wallner, business manager at lipid 4life. “In order to implement the principle of dual lipid oxidation our products contain a unique combination of MCT and a high dosage of omega-3 fatty acids (3.5 grams/200 milliliters). They are ready for consumption, contain 300 calories per 200 milliliters and induce a feeling of long-lasting satiety because of their high fat content.”

These ingredients and products are just the beginning of what will become a much larger category of foods and beverages for today’s consumer. Remember, dairy foods are the ideal carrier for many of these ingredients.