Nutrition Connection: Healthy Eating: Fact vs. Myth

(reprinted from Dietary Manager, May 2009)

The topic of “healthy” is one of much discussion among health professionals and diet book authors, but laying out some basic facts can help determine what is healthy eating.

Basics of Energy Balance

Starting at the beginning means reviewing the basics of energy metabolism. The word energy is synonymous with the word calorie since a calorie is a measurement of energy released by protein, carbohydrates, and fat when they are heated. Energy balance is defined as the measure of how calories in relate to calories consumed. Individuals can be in positive, negative, or equal energy balance. Positive energy balance occurs when calories consumed exceed calories burned. This occurs during times of growth and, of course, weight gain. Negative energy balance occurs when calories burned exceed calories consumed, and this occurs during illness, starvation, or weight loss. Finally, equal calorie balance means that calories in and out are the same and the outcome is a stable weight. This can, however, occur when calories consumed are very high or if calorie choices aren’t the healthiest.

Calorie balance is important to healthy eating since healthy eating focuses not only on a healthy weight, but on the right food choices to support the body, so how we make calorie choices is important. What we eat is influenced by internal and external cues. Internal cues include hormonal actions, satiety, satiation, hunger, and appetite.

Why We Eat

Hunger is the physiological need for food, whereas appetite is the psychological desire for food. Hunger causes us to eat whatever we can find, whereas appetite sets forth a desire for certain foods. Hunger and appetite work together to shape our food choices.

Environmental factors can also impact what we eat and they are external cues. Cultural, social, and the sensory appeal of food can all lead us to eat even when we aren’t hungry. Knowing how we make our food choices and what factors affect those choices are first steps in developing healthy eating plans. The second aspect of healthy eating is understanding the science behind healthy eating.

Healthy Eating Guidelines

Currently, the 2005 Dietary Guidelines for Americans set the foundation for healthy eating plans. While the American Heart Association has a slightly different set of guidelines, their recommendations for healthy eating are also based on the Dietary Guidelines, as are those of the DASH diet plan. The major differences in the latter two plans are the emphasis on heart health and blood pressure control in both. The 2005 Dietary Guidelines are based on the science of healthful eating to prevent disease and promote health. The guidelines are currently being reviewed for revision in 2010 as a part of the mandatory five year review process.

MyPyramid.gov is the visual depiction of the guidelines and it clearly shows several concepts of healthy eating. First, it shows that three of the food groups, grains (orange), vegetables (green) and fruits (red), make up more than one half of the recommended intake. Second, the food groups are depicted to show varying amounts of each group to achieve a healthy eating plan. Third, MyPyramid shows the importance of activity and a step-by-step process with the visual of a person climbing the pyramid.

While the dietary guidelines reflect the science of healthy eating, the plethora of fad diets reflects the variety of quick fixes which often lack any science base. Fad diets as a whole are characterized by their promise of quick and easy results, often the elimination of one or more food groups and the claim of having the magic answer, but rarely are they designed for a lifetime. The problem with fad diets is that they frequently eliminate or severely restrict carbohydrates, which are the body’s main fuel source. Many fad diets are high in animal fat, which can lead to increased heart disease risk. With the elimination of food groups, there is often a gap in vitamins and minerals needed for health. So what are the facts on fads? Let’s look at a few examples.

Fad Diet Facts

The Atkins Diet and the Ultimate New York Diet Plan are built around the concept that carbs are the cause of weight gain, so they are restricted significantly. Since calories can only come from carbs, protein, and fat, this severe restriction means the majority of calories are from protein and fat, with fat providing about 50 percent of the day’s calories. The Ultimate New York Diet Plan does emphasize consumption of leaner protein choices and even suggests that nuts and beans should be used as a protein source, thus making it lower in saturated fat than the Atkins Diet. The severe restriction in carbs results in a low intake of vitamins C, D, E, and Thiamin and of the minerals calcium, iron, zinc, and potassium. Both diets are low in fiber, which is a problem for regularity, but can also pose health problems due to the lack of plant compounds found in fiber which help promote health and fight disease. One plus of the Ultimate New York Diet is the recommendation of 45 to 60 minutes of daily activity.

The South Beach Diet is similar to the previous diets in that it starts out with a low carbohydrate content but very quickly increases the intake of whole grains, fruits, and vegetables to recognize the importance of these foods to overall health. The diet provides between 1400–1500 calories, so the low calorie intake is one of the reasons it promotes weight loss.

Two other diet plans that claim to aid weight loss and promote healthy eating are Dr Phil’s Weight Loss Solution and the Raw Foods Diet. Dr Phil sticks for the most part with his specialty of behavior change, but he does provide lists of good and bad foods, a concept that doesn’t promote healthy eating. The Raw Foods Diet is focused on the concept that nutrition is better when foods aren’t cooked, something that isn’t supported by science and certainly a good example of a gimmick or magic answer to achieve health. Scientific evidence shows no benefit to the raw foods concept and, in fact, it can pose some safety risk.

These few examples demonstrate the common thread of fads, missing science to explain them, blaming some foods for weight gain or proclaiming some as the answer to health, and overall they show plans that can’t be maintained for life.

Making the Change to Healthy Eating

The facts on healthy eating support the inclusion of carbohydrates, lean protein choices, and moderate amounts of fat. Healthy eating plans provide the right carbohydrates from grains, fruits and vegetables and identify oils as healthier fat choices. Developing a healthy eating plan takes a little bit of time, but taking it one step at a time can make it simple. Start your path to healthy eating by assessing your current food intake and then comparing that to MyPyramid. When you see gaps, develop a plan to improve your intake one step at a time. Taking it one step at a time ensures that you will develop an eating plan you can maintain so that you learn how to eat healthy for the rest of your life. Making changes in eating not only requires knowing what you need to change and developing that plan, but it requires understanding how we make changes.

Behavior change is a process, and how people change varies, but there are four basic models of change: Stages of Change, Health Belief, Consumer Information Processing, and Social Learning. While most consumers don’t need to understand these models or even know which one they follow, what is important is to understand that all behavior change follows a path of knowing what you want to change, why you want to change, and how you will benefit from the change. When it comes to healthy eating, the answers are simple: changing what you eat can improve health, quality of life, and hopefully aid longevity.

The Bottom Line

The bottom line is that healthy eating is a lifestyle that includes a variety of enjoyable foods in the right portions. Healthy eating is also flexible, so that it meets your needs.

By Connie Diekman, MEd, RD, LD, FADA

Connie Diekman, MEd, RD, LD, FADA is director of university nutrition at Washington University in St. Louis, St. Louis, MO. She is a past president of the American Dietetic Association.