Our love of junk foods has long been blamed for contributing rising rates of obesity. New research suggests that the sheer variety of high-calorie foods available to consumers may be pushing them to overeat.
A body of research shows that the growing number of food choices available in the US and other industrialized nations may be an important contributor to our expanding waistlines. Experts advise people to include a variety of foods in their diets to ensure proper nutrition. But in the Western world, variety is most apparent in the processed, high-calorie snack foods that line supermarket shelves, not fruits and vegetables.
The problem with variety, according to US researchers, is that when faced with multiple snacking options, people may eat beyond the point of hunger in order to get a taste of all that is before them. The researchers reported on their review of 39 studies on dietary variety and eating habits in animals and humans. These studies all suggest that greater variety in "highly palatable" foods, within a meal or in the diet as a whole, spurs overeating.
For example, studies in which participants could choose from different types of sandwiches or from a range of snack foods showed that they ate more when they had options, rather than just one type of sandwich or snack.
The reason seems to be that as we eat one food, not only do we begin to feel full, but the food also begins to lose its "pleasantness." But a nearby food that is different in taste or texture may still seem pleasant to the senses, and that may partially override feelings of fullness. So while a full person may not reach for a second tuna sandwich, he may go for a roast beef sandwich because it is a different and appealing taste sensation.
This theory is particularly relevant to snacking. A person who has a kitchen full of various snack foods might munch more calories than the person who stocks bags of potato chips only. On the other hand, research into food variety suggests that a person probably cannot get too many different kinds of nutritious, lower-calorie foods such as fruits and vegetables.
This research suggests that allowing only one or two types of snack food into the house will result in people getting fewer of their daily calories from them.
All research on this web site is the property of Leslie Beck Nutrition Consulting Inc. and is protected by copyright. Keep in mind that research on these matters continues daily and is subject to change. The information presented is not intended as a substitute for medical treatment. It is intended to provide ongoing support of your healthy lifestyle practices.