What is calories

And you burn off some calories without even thinking about it — by walking your dog or making your bed. But it is a great idea to play and be active for an 1 hour or more every day. That means time spent playing sports, playing outside, or riding your bike. It all adds up. Being active every day keeps your body strong and can help you maintain a healthy weight.

Watching TV and playing video games won't burn many calories at all, which is why you should limit those activities to no more than 2 hours per day. A person burns only about 1 calorie per minute while watching TV, about the same as sleeping!

Reviewed by: Mary L. Gavin, MD. Larger text size Large text size Regular text size. Are Calories Bad for You? How the Body Uses Calories Your body needs calories just to operate — to keep your heart beating and your lungs breathing. Select personalised ads.

Apply market research to generate audience insights. Measure content performance. Develop and improve products. List of Partners vendors. Calories in the foods we eat provide energy in the form of heat so that our bodies can function.

This means that we need to eat a certain amount of calories just to sustain life. But if we take in too many calories, then we risk gaining weight. To make matters even more complex, all calories are not the same.

You can consume calories by eating a candy bar, for instance, or by eating 30 cups of lettuce. Understanding exactly what a calorie is, and why we count them, can help when making dietary decisions. A calorie is a unit of measurement. Specifically, it is defined as the amount of heat needed to raise the temperature of one gram of water by one degree Celsius.

When the word "calorie" is used in reference to food, people are usually actually talking about the number of kilocalories a specific item has, which is what is listed on nutrition labels. One large kilocalorie kcal is the equivalent of 1, small calories. The calories we eat supply our bodies with the energy needed to live and stay healthy.

Everything we do relies on the energy that comes in the form of calories, whether it is sitting on the couch or running a marathon. Part of the confusion with calories is because calorie count alone does not dictate whether a food is nutritious. If a food supplies vitamins, minerals, fiber, or protein, its calories deliver more value to your body; these foods are sometimes called " nutrient-dense. Different types of food provide different levels of energy; the three macronutrients are not equal in the number of calories they provide.

Protein and carbohydrates supply less than half of the calories per gram as fat. Because fat provides more calories per gram, some people try to limit it in their diet. But some types of fat are necessary for a healthy body. Polyunsaturated fat , for example, helps you to maintain a healthy heart. And even though carbohydrates provide fewer calories than fat, refined carbohydrates provide fewer nutrients than complex carbs.

Refined carbs are more energy-dense, while complex carbs are nutrient-dense. The — Dietary Guidelines for Americans indicate that the daily recommended caloric intake for adults can range from 1, to 3, calories per day. This is a general estimate, as there are many variables to consider when determining an ideal daily caloric intake. For instance, the calorie needs for males are slightly higher 2, to 3, calories per day than the needs for females 1, to 2, calories daily according to these guidelines.

Your caloric intake also depends on other factors, such as your age, activity level, and metabolism. It is often estimated that if you consume approximately 3, excess calories you will gain one pound, though this has been disputed. But what's not controversial is that if you want to lose weight, you need to create a calorie deficit : Take in fewer calories than you use.

Some weight-loss experts believe that a calorie is a calorie. Their philosophy is that, to lose weight, you simply need to consume fewer calories and burn more. However, some calorie types provide weight loss benefits.

For example, calories from protein are helpful in building and maintaining muscle. When you have more muscle, you are better able to stay active during the day and burn more calories.

And calories from foods rich in fiber help you feel full and satisfied throughout the day, which is helpful when trying to lose weight.

Using an online calculator can help you determine how many calories your body needs to lose weight based on your age, height, sex, activity level, and weight loss goal. It's important not to cut calories too drastically, unless you are specifically directed to do so by your doctor.

Going on a very low-calorie diet can put your health at risk and cause problems such as constipation, nutrient deficiencies, and gallstones. A 1- to 2-pound decrease in weight per week is considered a healthy and sustainable rate of weight loss. Calories in food provide essential energy. But if you consume too many, you can gain weight. These excess calories are stored as body fat.

Many of these can be downloaded and used for free. The NHS cannot verify their data, but they can be helpful to track your calories by recording all of the food you eat in a day. Some restaurants put calorie information on their menus, so you can also check the calorie content of foods when eating out. The amount of calories people use by doing a certain physical activity varies, depending on a range of factors, including size and age.

The more vigorously you do an activity, the more calories you'll use. For example, fast walking will burn more calories than walking at a moderate pace. Find out how the body burns calories in. If you're gaining weight, it could mean you have been regularly eating and drinking more calories than you have been using. To lose weight, you need to use more energy than you consume, and continue this over a period of time.

Get used to counting calories and use our calorie counter. Find out how to make healthy changes to your diet and lose weight. If you need help losing weight, why not try the free NHS week weight loss plan.

Page last reviewed: 23 August Next review due: 23 August Understanding calories - Healthy weight Secondary navigation You and your weight Weight facts Hidden causes of weight gain 9 medical reasons for putting on weight How can I speed up my metabolism? The truth about carbs. Understanding calories Very low calorie diets Calorie checker. Find out your BMI.

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