Definition: Quality: The significance of diet quality to health and nutrition is a fundamental element of our definition of a nutritionally sound diet. Essentially related to the nutrient composition of an individual’s body and how it relates to her or his daily activities and goals. There are five factors or facets of diet quality that have particular importance in defining good nutrition and achieving optimal health. They are nutrient content, calorie density, dietary fat, dietary fiber, and essential fatty acids. Other important factors include the ability of a food to maintain or promote the health of an individual’s organs, physical structure, and overall health.
Importance: Dietary pattern is the foundation of all nutrition. As a primary course of action, it determines the nature, quality, and quantity of food consumed in a typical day. It is this diet quality that determines an individual’s nutritional needs and accordingly any changes in diet that may need to be undertaken for the maintenance of the same. Hence, the choice of a single nutrition program or diet must be based on a diet pattern.
Nutrient Content: The nutritional value of foods is determined by their chemical compositions. Therefore their nutrient composition is essential. What is diet quality if the nutrient compositions are well-balanced? An appropriate balance of essential nutrients is necessary for optimum health and longevity. In fact, health is intimately connected to nutrient quality.
Calorie density: The calorie density of food refers to the number of calories per serving. Commonly, a high-calorie food has more calories than a low-calorie food. This concept is illustrated by the widely-publicized Glycemic Index, which rates the rise in blood sugar levels in the blood following consumption of certain foods. High-calorie foods have been shown to increase the risk of both diabetes and heart disease. In contrast, low-calorie foods are associated with weight loss, lower risks of certain types of cancer, and cholesterol lowering. Hence, when considering what diet quality is, higher-income individuals would be expected to eat foods with a lower glycemic index rich in essential nutrients and devoid of excess calories.
Individual Energy Balance: A dietary quality that reflects the energy needs of an individual throughout the day. An individual’s food choices reflect their emotional state, physical capabilities, mental capacities, and family’s needs. Hence, when changing dietary patterns to improve overall diet quality, an individual’s energy balance should also be considered. The concept of energy balances helps determine the amount of dietary fiber, carbohydrates, proteins, and fats included in any particular meal.
Healthy Eating Index: A tool used for determining the nutritional content of foods, particularly in caloric intake, fat, carbohydrate, fiber, and potassium/potassium content. This index aims to provide a simple yet effective means of determining dietary guidelines, especially when reducing or eliminating unhealthy foods. Unlike other dietary guidelines, the healthy eating index has no set limit on the number of foods to be eaten; instead, the healthy eating index focuses on the food’s nutrient content per serving. The healthy eating index also considers the food environment, food type, dietary restrictions, and portion size.
The Healthy Diet Pyramid: This diet quality index is an indicator of food security and nutritional quality. The Healthy diet quality index is determined by the number of nutrient categories food offers and its percentage in the daily diet. According to the Healthy diet quality index, whole grain foods are lower than other grains. Low-fat dairy products are ranked higher than other dairy foods, while whole fruits and vegetables rank higher than other fruits and vegetables. Grains, nuts, fruits, and vegetables rank highest in the Healthy diet quality index.
Indexing foods’ nutrient composition provides important insights on dietary choices and assists in determining the overall balance of nutrients in the diet. An overall balance of nutrients and low-calorie intake promotes good health. Foods that have high nutrient content but low calories comprise low in calories but high in nutrients. High-nutrient but low-calorie foods are said to be good diet quality indicators. Nutrient composition is an important aspect of the overall equation for weight loss and maintenance.