We’ve all heard of metabolism. Most of us know that our metabolism affects our body’s ability to burn through calories quickly. I’m sure we’ve all looked at friends who seem to be able to throw down piles of food without gaining weight, and made the comment “you must have amazing metabolism.”
But what is metabolism, really? Is it something that’s fixed, or can we change it? If we’re one of those people cursed with a slow metabolism, are we destined to be overweight? Let me take a minute to provide the basics on metabolism, how it regulates our energy requirements, and, of course, what we can do to increase it.
What is Metabolism?
Metabolism includes all the chemical and physical processes in our body that produce or use energy. The most obvious example of metabolism is digesting food. Metabolism also includes breathing, contracting muscles, and several other natural processes in the body. Any time we eat, food is digested in the stomach and absorbed into the blood. It’s then used either for energy or stored in the body for later use.
Basal Metabolic Rate
We all have a natural rate at which we burn through the energy (calories) we take in through food. Known as basal metabolic rate, or BMR, this number is measured in the amount of calories the body needs to perform its basic functions like breathing, digestion and the beating of the heart. Your BMR plays the biggest role in the amount you can eat each day without gaining weight. BMR is influenced by genetics, body size and composition, age, and sex. No two people have the exact same BMR.
Daily Energy Requirements
You total daily energy requirement, or the amount of calories you need each day, is determined by a combination of your BMR and one additional, highly important factor: physical activity. The more activity you get each day, the more energy your body needs to maintain its weight. For every 30 minutes of exercise you get each day, your body needs about 250 to 500 additional calories.
Two factors can help improve your BMR, and you’ve heard them before: exercise and diet.
1. Exercise is the most important step you can take to improve your metabolism, accounting for about 20 to 30 percent of your daily energy requirements. When you exercise, your body learns to process nutrients more quickly and efficiently. Because muscle burns calories about three times as fast as fat does, building muscle can improve your BMR. So make sure to get not only aerobic exercise, but hit the weights, too. The more intense you exercise, the more energy your body will need.
2. The natural process of digestion accounts for about 10 percent of your body’s metabolism. After you eat food, your body requires additional energy several hours following the meal to digest, absorb, metabolize, and store nutrients. This is why you can improve metabolism by eating several smaller meals throughout the day versus two or three large ones. Certain foods also have a higher thermic effect and can naturally boost metabolism. Examples include hot peppers, foods high in protein (like lean meats and legumes), coffee, and green tea.