Who says you have to starve to lose weight? Filling up on low-energy, high-volume foods -- namely fruits and vegetables -- can help you lose weight.
If you're among the millions of Americans who are on a diet, you're probably feeling a little hungry right now. Feeling hungry and deprived is not an unusual consequence of the typical weight loss diet that stresses restricting food to lose weight. Even though "eat less" is the mantra of the weight loss industry, dieting does not have to be about deprivation and hunger.
Barbara Rolls, Ph.D., professor of Nutritional Sciences at Penn State University and author of "The Ultimate Volumetrics Diet," thinks she knows why you're hungry. Most diets recommend reductions in portion size and giving up your favorite foods as a way to reduce calories and lose weight.
"The amount of food you can eat to lose weight, or even avoid gaining weight, will be too small to satisfy your hunger," explains Rolls, who carries out research on how the quantity and quality of foods affect weight loss and weight maintenance. The ensuing hunger caused by tiny portions can derail a dieter's resolve.
Filling up on low-energy foods
What if you could eat more food instead of less? That's the idea behind "volumetrics," the phenomenon of filling up on foods of low energy or calorie density, which are foods that have fewer calories per unit of weight, such as fruits and vegetables. Low-energy foods have fewer calories for their weight than an equal amount of food that is more energy dense, such as high-fat meat or cookies.
Rolls' research has revealed that, for the most part, people tend to eat a consistent amount of food by weight each day, regardless of the number of calories and nutrients in the food. However, if you choose foods that are lower in calories while moderating the portions of your favorite, more calorie-dense foods, you will consume fewer calories overall, feel fully satisfied, and lose weight.
Simply put, this concept means loading up on lots of low-energy, high-volume fruits and vegetables, such as green salads, vegetable soups, tomatoes, carrots, cucumbers, melon, berries, and oranges in order to provide a greater sense of satiety or fullness during the day.
If you fill at least half of your plate with fruits and vegetables -- as the U.S. Department of Agriculture recommends -- you displace extra calories found in more energy-dense foods, such as meats, starches and fats. As an added bonus, you will consume more servings of health-protective fruits and vegetables -- just what the doctor ordered.
Research indicates that people whose diets are high in energy-dense foods, such as those high in added sugars and fats, and low in fruits and vegetables, weigh more than people whose diets focus on low-energy foods (Journal of Nutrition, 2011.) Studies also have found that a low-energy density diet, along with behavioral therapy, is a successful method of lowering calories, eating a more nutrient-dense diet, and losing weight.
High-water foods offer satiety
Foods that are low in energy density tend to be high in water content, such as most vegetables and fruits, including lettuce, kale, oranges and apples. High-water foods are more filling, but simply drinking a glass or two of water before the meal doesn't seem to fill you up in the same way.
In a 1999 study published in the American Journal of Clinical Nutrition, Rolls demonstrated that water served as a beverage with food did not affect fullness, while high-water foods, such as soup or lettuce salad, was effective. Water quenches thirst, not hunger. You might feel full after drinking eight ounces of water, but the water leaves the stomach quickly so the feeling of fullness does not last.
Vegetables as appetizers
Filling up on high-volume, low-energy density foods may be an effective method for controlling weight, even before you start your main course. According to a study conducted by Rolls and published in Appetite in 2007, eating vegetable soup 15 minutes before a meal resulted in 20 percent fewer calories being consumed at the meal.
Similar results were found when people ate a small vegetable salad prior to the meal. Having a cup of vegetable soup or a green salad before the meal helps to take the edge off hunger, and fills you up enough so that you can control what you eat at the meal. However, these benefits might not hold true if the meal starts with a high-energy density starter course, such as a salad drenched in a high-calorie dressing or a thick creamy soup laden with fat.
What about the meal itself? After a pre-meal appetizer of a very low-calorie dense food, Rolls suggests you follow it up with a moderate portion of lean protein, a starchy vegetable or whole grain, and lots more vegetables. Eating a variety of colorful vegetables with each meal helps to fill up your plate, as well as your stomach.
Another strategy is to prepare entrees that are modified in energy density. This can be achieved by taking a traditional entrÃ©e recipe, and skimming the fat and boosting the vegetables. For example, you can replace high-fat meat lasagna with a lower-calorie, vegetable-rich lasagna.
In a study published in Obesity in 2012, lower energy entrees proved successful: the people who were served them instead of traditional entrees consumed fewer total calories during the entire day (16 percent less calories for men and 14 percent less for women.)
There are many techniques you can use to bulk up your meals with fruits and vegetables. Ellie Krieger, M.S., R.D., host of Food Network's Healthy Appetite and author of "Comfort Food Fix," suggests that you add pureed fruits, like bananas or canned pumpkin, to pancakes or quick breads, sautÃ©ed chopped vegetables to meatloaf, and butternut squash puree to macaroni and cheese in order to increase nutrient density, while decreasing the calorie density.
(Environmental Nutrition is the award-winning independent newsletter written by nutrition experts dedicated to providing readers up-to-date, accurate information about health and nutrition in clear, concise English. For more information, visit http://www.environmentalnutrition.com.)