The message to eat a healthy diet for good health is everywhere. But what is a healthy diet? Obviously, the definition of a healthy diet should indicate that the diet provides good nutrition. Surprisingly and unfortunately, this is too often not the case.

To provide good nutrition, a diet first needs to include an adequate variety and amount of foods to meet human needs for all of the essential nutrients necessary for maintaining health. Meeting essential nutrient needs is the first step in good nutrition. Skip that first step and at some point health problems are guaranteed.

This concept of meeting essential nutrient needs seems so basic on the surface — and it is — but even health professionals often do not understand how indispensable it is to obtain required amounts of all of the essential nutrients. Too often, people providing diet and nutrition guidance put what seem like important components of eating healthy as their first step and don’t even consider the absolute requirement to meet the body’s needs for essential nutrients. These essentials include water, protein, carbohydrates, vitamins, minerals and even some fat.

Fat is necessary to provide essential fatty acids and for the absorption of the fat-soluble vitamins A, D, E and K.

Question: Isn’t achieving a healthy body weight more important than meeting essential nutrient needs?

Answer: Definitely not. In fact, an inadequate supply of essential nutrients can sabotage weight and fat-loss efforts. When people consume a diet that is limited in calories, it becomes significantly more challenging to obtain all of the essential nutrients, including protein. When protein intake is too low, there is a slow but steady loss of the body’s lean tissues. This loss is mostly from muscle, but protein deficiency also contributes to bone loss and intestinal problems.

Muscle loss shows up on the scale as weight loss that does not represent the desired fat loss. Losing these lean tissues lowers calorie needs. If inadequate protein and calorie intake continues, calorie needs continue to decline and fat storage is enhanced.

This can result in a body that needs very few calories to maintain excess body fat and, consequently, it becomes increasingly difficult to lose fat. This is true even if a person is eating lots of fruit and vegetables and whole grains, as many weight-loss diet plans recommend.

Q: Can a person obtain adequate amounts of essential nutrients by eating a diet containing food labeled as healthy?

A: Not necessarily. It often is stressed that fruit, vegetables and whole grains are good for us, and they are; however, there are limits regarding the amount of these foods a person should eat.

The recommendation to eat more fruit and vegetables is based on the concept that most Americans do not eat enough of these foods. But don’t misinterpret this message.

If you primarily eat only these healthful foods, you are not likely to consume adequate amounts of all essential nutrients, especially protein, iron and zinc. You may also consume excess amounts of trace minerals, such as manganese, that can cause serious health issues.

Also, remember fruit is high in sugar and eating more than 1-1/2 cups of fresh fruit daily may add excess calories that lack some key essential nutrients that other foods provide.

Our next column will address the nutrient deficiencies and health problems that are likely to develop from diets limited to so-called healthy foods that don’t meet all essential nutrient needs.