Governmental guidance

Although a healthy diet is based upon nutrition, people eat foods and not nutrients; as few people know which foods supply which nutrients, allowing people to self-regulate their diets means that they run the obvious risk of deficiency. Due to past difficulties of educating people about nutrient intake, governments have opted to counsel on what foods to eat rather than on what nutrients to ingest.

Most states set guidelines for a healthy diet -- these usually vary slightly from country to country based upon demographics. These guidelines do however usually share the same recommendations of eating less fried or fatty foods to reduce cholesterol. Many guidelines suggest replacing certain foods with healthier alternatives that supply an abundance of nutrients, for instance using legumes or beans within a salad or pasta.

As BMI and weight changes from person to person, the general Reference Nutrient Intakes (RNI) set by governmental institutions may be somewhat lacking for some people, despite the fact that the RNI is generally calculated as higher than the average nutrient intake. It is even thought that some people may have needs above that of the RNI, meaning even if a person achieved nutrient intake, they would still not be fulfilling the RNI. The only real way to know the RNI for a person is to implicitly monitor the intake of nutrients and amount of exercise.