In previous months we’ve discussed the importance of variety and moderation in a healthy diet. This column discusses the nutritional principle of balance — required to meet critical nutrient needs — along with variety and moderation.

There’s an abundance of misunderstanding surrounding the concept of balance. Most messages are tied to caloric intake or the importance of adding produce, whole grains and beans to your diet. But such overly simplistic concepts can lead to poor nutritional decisions and even health risks.

Question: What is “nutritional balance”?

Answer: Nutritional balance refers to having the right mix and the right amounts of essential nutrients needed to support the thousands of chemical reactions necessary for life and ongoing health. As part of that process, the body’s cells constantly die and must be replaced, requiring critical nutrients. For optimal cell function, cell loss must be equaled by an adequate supply of nutrients to maintain the replacement of cells.

Q: Why is it a problem to think of plant foods as the better food choice?

A: No single food group contains all nutrients in concentrations the body needs, so promoting certain foods as “good” or “bad” can diminish the importance of a diet that consists of a combination of foods.

Consuming too little or excessive amounts of certain nutrients can cause problems. For example, plants, including freeze-dried plant supplements, contain fiber. While fiber can benefit gut organisms, excessive amounts can inhibit the absorption of some essential minerals, increasing the dietary requirement for these nutrients.

Q: What is a good way to adopt a more balanced eating style?

A: There is no single answer. It depends on your eating style and the foods you choose to eat. However, an omnivore diet of animal and plant foods provides the simplest way to obtain all essential nutrients. As a rule of thumb, if your diet is mainly meat and white rice, it’s time to bump up your consumption of a good variety of plants.

If your plant-based diet contains primarily fruits and vegetables, including more legumes, grains and animal protein could be helpful. A mixed vegetarian diet with eggs and dairy can provide an adequate supply of nutrients, including protein.

The most challenging diet to balance is vegan. The composition of plants inhibits the absorption of iron and zinc, and the diet requires a vitamin B12 supplement to obtain that essential nutrient.

Moreover, protein requirements are based on body weight, and plant protein foods contain considerable amounts of the trace mineral manganese. Heavier people on a vegan diet will struggle to consume adequate plant proteins without exceeding safe manganese levels.

The bottom line: Consuming all essential nutrients in the right amounts involves variety, moderation and nutritional balance.

Joannie Dobbs, Ph.D., C.N.S., and Alan Titchenal, Ph.D., C.N.S., are retired nutrition faculty from the Department of Human Nutrition, Food and Animal Sciences, College of Tropical Agriculture and Human Resources, University of Hawaii at Manoa.