By Michèle Turcotte, MS, RD/LDN

What is metabolism?

Metabolism is the body’s process of building molecular structures from nutrients (anabolism) and then breaking them down for energy production (catabolism). Simply stated, metabolism is the chemical and physiological processes whereby the body builds and maintains itself by breaking down food and nutrients to produce energy. Chemical processes distribute the nutrients that are absorbed into the blood after digestion. When you increase your metabolism, your body burns more calories and you experience higher energy levels.

3 factors of metabolic rate

Your total metabolic rate is determined by:

1. The rate at which your body uses energy for vital processes, such as breathing (i.e. your basal metabolic rate, or BMR).
2. The rate at which you burn energy during physical activity.
3. The rate at which you burn energy during food digestion (otherwise known as the thermogenic effect of food).

Raise your metabolism with exercise

Raising your metabolic rate can be achieved by slightly altering your diet and lifestyle habits. Think of your body as a machine. Optimal fuel and maintenance ensure peak performance. The best way to jump-start your metabolism is by exercising. Exercise reduces body fat and increases lean muscle mass. Aerobic exercise, like walking or cycling, has the added bonus of speeding up your metabolism for 4-8 hours after you stop exercising. Additional calories continue to be burned off long after you stop exercising.

Diet influences metabolism

As far as dietary habits are concerned, eating breakfast is essential! Your body is deprived of food during the night (essentially an over-night fast), which causes your metabolism to slow down. If your cells don’t receive sufficient nutrients post-fast, they will adapt—functioning less efficiently on smaller amounts of food. This will actually enable your body to store more fat to use during times of nutritional deprivation (like when you are asleep)! Eating six small meals a day keeps your body’s fuel supply consistent…and your metabolism revved up. Because your metabolism naturally slows down in the afternoon and evening, it’s important to avoid eating late at night.

Consistency is key to maintaining a high metabolic rate

Consistency is important because your body metabolism adapts to your current weight. If you have been dieting or skipping meals your body's metabolism slows down to compensate for the lack of nutrients. When lean people overeat their metabolism speeds up and when obese people diet their metabolism slows down. The key is a balance of exercise and diet.

Eat fewer high-fat foods and less total calories. Choose healthy, nutrient-dense foods, such as lean protein and vegetables. Increase dietary fiber, but limit sugary foods and alcohol. The best foods to increase your metabolism and help you lose weight are fish, lean poultry, dark green leafy vegetables, tomatoes, fruits, whole grains (such as brown rice, barley and oats), and at least eight glasses of water a day. Your plate should contain at least a half of vegetables, a quarter of lean protein and a quarter of high fiber whole grains for optimal nutrition and performance.

You body metabolizes food differently

• Carbohydrates. When your cells need energy, they break down carbohydrates first. Then, they burn fat. And then, they burn protein. Your body converts carbohydrates into a form of sugar called glucose because it is most easily used as fuel by your body. Excess carbohydrates and fat are converted into fat for storage.
• Fat. Unfortunately, your body converts the fat you eat into body fat very efficiently. However, if you exercise and eat wisely you will burn those fat stores and increase your metabolism.
• Protein. A meal consisting of only protein can burn up to 25% of the calories of the meal itself in the digestion and absorption process. However, only eating protein inhibits the body’s ability to access the vital vitamins and minerals which are essential for optimum health. Although increasing your consumption protein may slightly increase your total metabolism, remember that the total thermogenic effect of food represents only about 5-10% of your total metabolic rate.

Altering your exercise and dietary habits on a whole is more important that eating more or less of certain foods.