Nutrient Density

Nutrient density describes the amount of one or more nutrients in a food or diet relative to a defined reference amount. In a traditional nutritional definition, it refers to nutrient content relative to the energy provided by the same food or diet and may be expressed as the amount of a nutrient per 1,000 kilocalories or per megajoule. More broadly, food-ranking systems may express nutrient content per 100 kilocalories, per 100 grams, or per serving .^1,2

The concept is useful because the amount of a nutrient in a food alone does not show how concentrated that nutrient is relative to the food's energy content or another reference amount. A food that provides relatively high amounts of selected nutrients for a given amount of energy can therefore be described as nutrient dense. When several nutrients are considered together, nutrient-profile models may be used to calculate or compare overall nutrient density .²

There is no single universally accepted nutrient-density score. Different nutrient-profiling systems may include different vitamins, minerals, protein, fiber, or other dietary components and may use different reference quantities. Some systems also account for components that are intended to be limited. As a result, whether one food ranks as more nutrient dense than another can depend on the method being used .²

Nutrient density is distinct from energy density. Energy density describes the amount of food energy relative to the weight of a food, commonly expressed as kilocalories per gram. Nutrient density instead relates nutrient content to energy or another defined reference amount. The two concepts therefore describe different characteristics of a food or diet .^1,2