Nutritional disorders are widespread, and may be more common in highly developed industrialized nations that poorer agrarian economies. While the latter may be more vulnerable to periodic and extreme swings in food availability, the former are more or less constantly over-provided with excess food intake. However, much of this may be inappropriate, and in a form which has low nutritional value, such as high calorifically-dense refined sugars and fats while being depleted in essential micro-nutrients, or more obviously fresh vegetables and fruits.

Over-nutrition is seen among people who have a
BMI >25 and becomes problematic in those with a BMI >30. When over-nutrition becomes a problem in a community, it first tends to appear among the affluent, and then among the lower classes and eventually the poor. Usually, it is the poor who end up with the worst malnutrition, suffering from excess weight while experiencing lack of high quality food in their diets - fast food, carbonated drinks (Coke, Pepsi) and candies are often consumed in place of more traditional, balanced diet components.

Adults in HK tend to have excessive consumption of animal protein, refined carbohydrates and fats relative to intake of vegetables, grains and fruits. Coupled with a decrease in activity, this results in a growing problem with obesity.

This kind of excess malnutrition currently affects about one person in three in Latin America, the Caribbean, North Africa, the Pacific Islands and urban Asia.