Calories are a unit of energy, but in diet and exercise, the term is used to mean kilocalories (kcal). Learn the difference and what these terms mean.

Calorie density, or energy density, refers to the number of calories per weight or volume of food. Compare, for example, 100 g of romaine lettuce, which contains about 17 calories, with the same ...

How much food a person should eat depends on their height, weight, age, sex, level of physical activity, health, genetics, body composition, and more.

Hidden calories in food and drink could cause you to gain weight without meaning to. Common sources include cooking oils and salad dressings.

WHEN you are navigating the complex world of nutrition, the calorie feels mercifully simple. A straightforward measure of the energy in our food, calories sit at the heart of conventional weight ...

What is a calorie-deficit diet—and how do you do it? Calorie-deficit diets are exactly what they sound like: eating fewer calories than your body burns each day. It can be done in a variety of ...

You can think of burning calories as “Step 1 of being alive,” said Herman Pontzer, a professor of evolutionary anthropology at Duke University. Food gives your body the fuel it needs to stay ...