Demystifying Metabolism

By Robyn Fadden

Every day, new fad diets promise to “boost metabolism” and result in dramatic weight loss, yet medical science confirms that no one-size-fits-all solution exists. When it comes to metabolism and health, every person is different – and thin doesn’t always mean healthy.

What medical science does know for sure is that metabolism, or more specifically, each person’s basal metabolic rate (BMR), can be measured by calories consumed and expended. As the saying goes: energy in, energy out. Calories consumed in food and drink and expended with physical activity – everything from breathing to running a marathon – are easily measurable, but understanding each person’s own metabolic state makes for a more complex calculation.

Medical professionals usually take five factors into account when estimating metabolic rate and determining how many calories a person should consume: height, weight, age, gender, and activity level. Height and weight provide basic information on the distribution of fat and muscle; metabolism slows as we age; men and women’s bodies have different levels of fat and muscle; and activity of any sort uses calories from the food  we eat, whether that be quickly digested carbohydrates or slower-to-digest  foods high in fat, protein, or fiber. Yet even that calculation isn’t perfect.

Often, people underestimate how much they eat, and overestimate how hard they exercise. Food scales and heart rate monitors make that job easier and provide important details. Even with a closely monitored diet and exercise routine, sometimes weight and health concerns continue. Hormone and other endocrine system issues such as thyroid and hormone levels, as well as diabetes, blood sugar responses to food, environmental factors, medications and other drugs, food allergies, and stress, all play a physical part in how our bodies metabolize energy.

But even with all of these factors in mind, metabolism is no great secret – though weight is an indicator of metabolic health, it isn’t the ultimate guide to it. For a clearer picture of our overall health, we should look closely and honestly at what we eat and how much we exercise, while regularly consulting medical professionals to test for existing imbalances.