Fat Loss and Metabolism: How You Burn Calories

Metabolism is the process by which your body converts the food and drink you consume into energy.

Calories in food and beverages are combined with oxygen during this complex process to release the energy your body requires to function.

Even when you're sleeping, your body requires energy to perform all of its "invisible" functions, such as breathing, circulating blood, adjusting hormone levels, and growing and repairing cells.

The number of calories used by your body to perform these basic functions is known as your basal metabolic rate — also known as metabolism.

Your individual basal metabolism is determined by a number of factors, including:

• The size and composition of your body. Even when at rest, people who are larger or have more muscle burn more calories.
  

• Your gender. Men typically have less body fat and more muscle than women of the same age and weight, implying that men burn more calories.

• It's your age. As you get older, your muscle mass decreases and your fat mass increases, slowing down calorie burning.

The energy requirements for your body's basic functions are fairly consistent and difficult to change.

Aside from your basal metabolic rate, two other factors influence how many calories your body burns per day:

• Food preparation (thermogenesis). Calories are expended while digesting, absorbing, transporting, and storing the food you consume. Approximately 10% of the calories from carbohydrates and protein consumed are used in the digestion and absorption of food and nutrients.

• Physical exertion. Physical activity and exercise, such as playing tennis, walking to the store, chasing after the dog, and any other movement, account for the remaining calories burned by your body each day. Physical activity is by far the most variable factor in determining how many calories you burn per day.

Nonexercise activity thermogenesis is what scientists call the activity you do all day that isn't deliberate exercise (NEAT).

Walking from room to room, gardening, and even fidgeting are examples of this activity. NEAT accounts for approximately 100 to 800 calories consumed per day.

Weight and metabolism

It's easy to blame your metabolism for your weight gain. However, because metabolism is a natural process, your body has a number of mechanisms that regulate it to meet your specific needs.

Excessive weight gain is only seen in rare cases due to a medical condition that slows metabolism, such as Cushing's syndrome or having an underactive thyroid gland (hypothyroidism).

Unfortunately, gaining weight is a difficult process. It's most likely a combination of genetics, hormonal controls, diet composition, and the impact of the environment on your lifestyle, such as sleep, physical activity, and stress.

All of these variables contribute to an imbalance in the energy equation.

You gain weight when you consume more calories than you burn — or when you consume fewer calories than you burn.

While some people appear to be able to lose weight more quickly and easily than others, everyone loses weight when they burn more calories than they consume.

To lose weight, you must create an energy deficit by either eating fewer calories or increasing the number of calories burned through physical activity, or both.

An examination of physical activity and metabolism

While you don't have much control over your basal metabolism, you can control how many calories you burn by increasing your level of physical activity.

The more you move around, the more calories you burn. In reality, some people who are said to have a fast metabolism are likely to be more active — and possibly fidgetier — than others.

Aerobic exercise, which includes activities such as walking, bicycling, and swimming, is the most efficient way to burn calories. Include at least 30 minutes of physical activity in your daily routine as a general goal.

If you want to lose weight or achieve specific fitness goals, you may need to increase your physical activity time even more.

If you don't have time for a longer workout, try breaking it up into 10-minute chunks throughout the day. Keep in mind that the more active you are, the greater the benefits.

Strength training exercises, such as weightlifting, are also recommended at least twice a week by experts.

Strength training is important because it aids in the development of muscle. Muscle tissue burns more calories per day than fat tissue.

Any additional movement aids in the burning of calories. Find ways to walk and move around for a few minutes longer each day than you did the day before.

Simple ways to burn more calories include taking the stairs more often and parking farther away from the store.

Even activities like gardening, car washing, and housework burn calories and help you lose weight.