Is Eating Less Really Key to Weight Loss? Interview on the Research

If you want to lose weight, or are looking for ways to manage your weight, could messages be any more confusing about how to do it?  Sometimes if you try simply eating less, you may get so hungry or feel so deprived you can’t stick with your resolution and end up overeating on high-calorie “comfort foods”.

You may have heard that fat in food is the enemy, or that you just need to eat lots of vegetables. Both those statements are over-simplifications that research does not support. Barbara Rolls, PhD, renowned for her research on calorie density and how it can be used for weight control.

Check below for the first section of my video interview with Dr. Rolls, chair of the department of nutritional sciences at Penn State University, in which she gives us the bottom line on calorie density. You’ll get important clarification of some nuances of how to use calorie density to help you manage your weight while eating healthfully.

(After you watch the video, read on for some practical ways to apply results of Dr. Rolls’ research.)

The Calorie Density Concept

Different foods vary quite a bit in how many calories they contain in similar size portions.  Foods that are more concentrated in calories are called “calorie-dense” foods.  You can eat the same total amount of food on a given day, but depending on how concentrated in calories those foods are – how calorie-dense – your calorie consumption ends up at a very different total.

You may sometimes hear this concept of calorie density referred to as “energy density”, because calories are actually the unit scientists use to measure the energy value of food.  This is confusing to many people, because “energy-dense food” sounds like a good thing – something that will help you feel more energetic or less fatigued. Wrong! Energy-dense foods help people who have trouble eating enough to meet their needs….people like Olympic or marathon athletes, or people seriously ill who have trouble eating.  If you’re getting all the calories you need, more don’t help.

For most of us, high energy density – more concentrated calories – means that in order to keep from eating more calories than we burn (and thus gaining weight), we need to keep portions very small.  That’s one of the things that people say makes weight control difficult for them.

Nuances for Weight Control

An overall eating pattern that’s low in calorie density provides filling amounts of food that make it possible to limit calorie consumption without being hungry.

• Be smart with vegetables and fruits

♦ Foods high in water and fiber and low in fat, such as vegetables and fruits, reduce your overall calorie density.

♦ Use less calorie-dense foods to replace foods concentrated in calories in order to reduce total calories you eat.

♦ For most people, it’s best not to rely on juice to boost your fruit and vegetable consumption.  Research suggests it won’t provide as much help for filling you up   and reducing calorie consumption as do solid fruits and vegetables.

♦ Adding large amounts of fat or sugar to vegetables and fruits increases their calorie density.

• Use fat wisely

♦ Fat is concentrated in calories, so choose lower-fat versions of high-fat foods and limit added fat.

♦ Studies show that with adequate vegetables and fruits, there is room for small servings of calorie-dense foods — such as healthy oils, nuts and seeds — within an overall diet low in calorie density.

♦ For overall good nutrition, cut down on foods high in fat that offer little nutritionally (such as donuts, cookies, ice cream, chips). Use moderate amounts of healthy fats to make vegetables delicious and enhance absorption of fat-soluble nutrients and phytochemicals (protective natural plant compounds). The traditional Mediterranean diet is a great example of this.

• Keep your eye on the big picture of calorie density in your overall eating habits. For most people, it needs to be part of an overall approach to weight management.  Other steps to address:

♦ Limit or avoid beverages concentrated in calories such as sugar-laden soft drinks and alcohol.

♦ Research shows that when large amounts of food are available, most of us eat more even if we don’t feel hungry.  If you’re trying to reduce calories, try serving portions about 25 percent smaller than usual of everything other than vegetables and fruits, and go back for more if you’re truly hungry.  Other than vegetables, don’t leave serving bowls on the table.

♦ If you eat in response to boredom or emotions even though you’re not hungry, learn new ways to respond to these cues.

♦ Make physical activity a regular part of your daily life.

The bottom line: To lose weight, you can use calorie density to help you cut total calorie consumption.  It’s not magic; it’s one tool that helps you build a sound strategy that works for you.

How to Put Calorie Density to Work: Check back for the next portion of my interview with Dr. Rolls to hear research-tested strategies for how you can use vegetables and fruits to reduce calorie density in ways that effectively help manage calorie consumption.

Resources

The U.S. Centers for Disease Control and Prevention (CDC) has tips for using calorie density (“energy density”) as a tool for weight management in the brochure, Eat More, Weigh Less?

References for Reading the Research

Kral TVE, R. L. (2004). Combined effects of energy density and portion size on energy intake in women. Amer J Clin Nutr , 79:962.

Ledikwe, J., Rolls, B. et al. (2007). Reductions in dietary energy density are associated with weight loss in overweight and obese participants in the PREMIER trial. Amer J Clin Nutr , 85(5):1212-21.

Pérez-Escamilla R, et al. (2012) Dietary energy density and body weight in adults and children: a systematic review. J Acad Nutr Diet.  112(5):671-84.

Raynor HA, et al. (2011) Dietary energy density and successful weight loss maintenance. Eat Behav. 2011 Apr;12(2):119-25.

Raynor HA et al. (2012) The Effects of an Energy Density Prescription on Diet Quality and Weight Loss: A Pilot Randomized Controlled Trial.  J Acad Nutr Diet..  2012 Sep; 112(9):1397-402.

Rolls B. (2010a). Plenary Lecture 1: Dietary strategies for the prevention and treatment of obesity. Proc Nutr Soc , 69(1):70-79.

Rolls B et al.. (1999). Water incorporated into a food but not served with a food decreases energy intake in lean women. Amer J Cliin Nutr , 70: 448-455.

Rolls, B., et al. (2006). Reductions in portion size and energy density of foods are additive and lead to sustained decreases in energy intake. Amer J Clin Nutr , 83:11-17.

This website is for educational purposes only. Information found here is not intended as a substitute for consultation with a healthcare professional.