Body Mass Index (BMI): A ratio of height to weight that is used as an indicator of body fat in the general population. BMI is calculated by dividing a person's weight by the square of his or her height. It is used to determine if a person is underweight, an appropriate weight, overweight or obese. Health risks greatly increase with a BMI of 30 and over.
Calorie: The unit for measuring the energy produced by food when oxidized in the body.
Nutrient: A substance in food that the body uses for energy, growth and repair of cells. Nutrients include fats, proteins, carbohydrates, vitamins and minerals.
Obesity: A condition in which a person weighs more than is considered healthy for his or her height. It is usually determined by body mass index, or BMI. If a person's BMI is over 30, that person is considered obese.
Portion size: The amount of a specific food or drink that you choose to consume.