Most of us are influenced by our own mental list of "good" and "bad" foods. Unfortunately, if we eat according to this good food/bad food focus, it can put us at risk for not meeting some of our basic nutrient needs.

QUESTION: How did we get into this "good" and "bad" way of thinking about food?

ANSWER: Before 1977 there was more focus on consuming the right variety and proportions of foods to meet essential nutrient needs. That’s what the food group systems were designed for. If you eat a variety of foods from each of the groups (fruits, vegetables, grains and dairy, along with meat, chicken, fish, eggs, beans and nuts) in the recommended amounts, you should get enough of all the essential nutrients.

Then, in 1977, when most of us were leaner and more active than now, a government committee published the "Dietary Goals for Americans." Also called the McGovern Report for the senator who headed up the committee, it played a major role in launching the good- and bad-food concept. It recommended eating more fruits, vegetables and whole grains and less added sugars and less food high in fat, saturated fat and cholesterol — foods such as eggs, butter, red meats and higher-fat dairy foods.

The loudest message that people heard was to cut the fat and cholesterol. Of course, many low-fat food options hit the market.

People who questioned the scientific validity of the report when it was released have pointed out that the document was written by a staff member who happened to be a vegetarian and had no background in medicine or nutrition research. Scientists who questioned the validity of the report were told by McGovern that "senators don’t have the luxury that a research scientist does of waiting until every last shred of evidence is in."

Q: Did cutting fat and cholesterol improve health?

A: After the McGovern Report, obesity and diabetes increased substantially. Also, there is an increasing number of studies finding little or no association between disease risk and dietary fat, saturated fat or dietary cholesterol for most of the population.

Q: Now that the average person is larger, what does that mean in terms of calorie and nutrient needs?

A: More sedentary people have lower calorie needs. Nutrient needs, however do not decrease. Heavier people require more protein to maintain their muscle mass, skeleton and blood volume. If calorie intake is reduced by cutting back on too many high-protein foods, people lose muscle mass instead of body fat. Muscle loss decreases calorie needs, and a diet with low protein quantity or quality can start a vicious cycle of malnutrition, setting the stage for fat gain and diabetes.

The heavier a person is, the more serious this slippery slope can become due to their greater protein needs. Consequently, racial groups that genetically have larger frame sizes are more likely to be short on protein and to gain excess fat on high-carbohydrate, lower-protein diets.

For an interesting summary of issues about the McGovern report, take a look at a historic short video available at hsalinks.com/1hPZNqa.

Alan Titchenal, Ph.D., C.N.S., and Joannie Dobbs, Ph.D., C.N.S., are nutritionists in the Department of Human Nutrition, Food and Animal Sciences, College of Tropical Agriculture and Human Resources, University of Hawaii-Manoa. Dobbs also works with University Health Services.