"Enjoy your food but eat less." That was on the cover of our March issue and was the opening statement in our story on the 2010 Dietary Guidelines. It's the simplest and most effective solution for the obesity crisis … but at the same time, easier said than done.
However, the study of satiety – what makes diners feel full – has come into its own in the past decade. Our report from the 2008 Institute of Food Technologists Annual Meeting & Food Expo called satiety-inducing ingredients one of the key trends at that show.
A June 2004 article in the American Journal of Clinical Nutrition identified a number of biomarkers – mostly peptides and hormones – which turn the urge to eat on and off. The researchers from Utrecht University and TNO Nutrition and Food Research, at Wageningen University in the Netherlands, noted there are also physiological factors, including time of day, family influences and others.
The biomarkers include short-term drops in blood glucose (which tell the person to begin a meal), plus longer-term changes in the level of the hormones leptin (which signals negative energy balance) and ghrelin (which appears to have an effect on both long- and short-term energy balance). These biomarkers are difficult to measure, and their total effect is still somewhat unclear.
An even earlier study reported in the September 1995 European Journal of Clinical Nutrition developed "A Satiety Index of Common Foods." Suzanne Holt of the Commonwealth Scientific and Industrial Research Organization (CSIRO), Australia, used white bread as a baseline and compared 240-calorie portions of various foods, as consumed by volunteers who then rated their feeling of fullness every 15 minutes over a period of two hours. The CSIRO assigned a satiety value of 100 for white bread. The same caloric count of brown rice provides 155 percent of the satiety and white rice 119 percent. The same caloric serving of boiled potato provides 323 percent of the satiety of white bread.
Using that research as a product development recipe would be difficult – try working oatmeal or oranges into your next product formulation. But there are more practical weapons available in the battle for satiety.
Protein is one. Scientific literature indicates that protein can elicit a stronger satiety effect over the short term than carbohydrates or even fat. We dubbed 2007 "The year of protein awareness" in a story, noting that "while Americans are not protein-deficient, the nutrient's roles in food and health are becoming more appreciated, and its connection to satiety is skyrocketing."
The year before, Kellogg Co. had created a Health & Wellness Division, which launched a line of protein-fortified Special K products. They were positioned as nutritious "shape management" tools, targeting consumers (particularly women) interested in weight loss. Sold in the diet and nutrition sections of grocery and drug stores, the line included Special K Protein Meal Bars with 10g of protein, Special K Protein Snack Bars with 4g of protein and, most interesting, Special K2O Protein Waters, the first broadly available brand of protein water, with 5g of protein per 16-oz. bottle.
The bottled waters have since been discontinued, replaced with single-serve mix packets that consumers can pour into a 16-oz. bottle of water. The point is still the same: Protein can stave off hunger.
Whey protein from dairy is a cost-effective and available source of protein for the above products. "Protein bars were originally developed for elite athletes and bodybuilders," notes Fonterra Ingredients. "More recently, there has been increasing recognition that these benefits now extend to … superior satiety effects." To that end, Fonterra markets PowerProtein for bars and snack foods and SureProtein for medical foods.
Similarly, Hilmar Ingredients offers whey protein concentrate, whey protein hydrolysate and whey protein isolate.
Glanbia Nutritionals offers similar ingredients, including Prolibra, a patent-pending whey protein milk mineral complex developed for weight management applications. It's been shown in clinical studies to reduce fat, maintain lean body mass and considerably reduce glucose response by reducing the glycemic index in common foods Provon A-190 is a new whey protein isolate system offering maximum functionality in low pH drinks while improving overall flavor.
The Almond Board of California points out one serving of almonds provides 6g of protein, as well as 3.5g of fiber (and other nutrients). The board also funded a 2009 study on chewing that found, among other things, that chewing almonds slowly may increase feelings of satiety or fullness.
Whole grains and fiber are other approaches to satiety. Dietary fiber is the part of plant foods that the body does not digest. Therefore, fiber adds very few calories but adds to a feeling of fullness. There are two types of dietary fiber used in food products: soluble fiber (which dissolves in water) and insoluble fiber (which does not dissolve in water and can be found in whole grain products and vegetables).
"Cardboard, no. Delicious, yes," is how General Mills promotes its line of Fiber One products, which run the gamut from cereals to bars to, most recently, yogurt. And Fiber One 90 Calorie Brownies are expected to debut soon.
Tate & Lyle promotes "that feeling of fullness" as a key benefit of its Promitor dietary fibers, as both corn fiber and resistant starch. They can be incorporated into a range of foods and beverages without compromising taste and texture, and they promote digestive health and immunity, as well as weight management.
Food-grade gums are usually associated with the texture or "look and feel" of food products. But TIC Gums reminds that gums add soluble dietary fiber. "Most gums are 80 percent soluble dietary fiber, providing more soluble fiber than oats, wheat bran and other better-known fiber sources," says Mar Nieto, senior principal scientist at TIC Gums.
And there are more exotic ways of suppressing hunger. InterHealth Nutraceuticals has had steady success with its Super Citrimax product. It's an extract of the plant Garcinia cambogia, which contains high levels of hydroxycitric acid bound to calcium and potassium. Somehow, the stuff suppresses appetite. Fuze and SoBe put it in some of their drinks.
DSM Nutrition has Fabuless, an oil-in-water emulsion the fine oil droplets of which are made from naturally occurring dietary lipids -- palm oil, coated with galactolipids from oat oil. Oat oil is naturally rich in so-called polar lipids, such as galactolipids. Thanks to them, Fabuless triggers the natural appetite control mechanism. By delaying the hunger signals that would normally be sent hours after a meal, consumers feel more satisfied than they would have been and consequently eat less.