Most people have very little understanding about what metabolism actually is - or does – but are keenly aware of its importance with the arrival of a new year and the subsequent setting of resolutions.
As Vox reports, people talk about metabolism as if it can be manipulated by taking a pill, downing some green tea or running faster.
But none of this actually explains the biological process, so Vox has broken it down into nine facts to help people understand what it is and how to think about it in the context of weight gain and weight loss.
- Metabolism is a series of chemical processes in each cell of the body that turn calories consumed from food into fuel to keep one alive, a researcher at the Mayo Clinic told Vox.
- One’s “resting” or “basal” metabolic rate measures how many calories are burned while at rest.
- The brain, liver, kidneys and heart account for about half of the energy burned at rest, while fat, the digestive system and muscles account for the other half.
- Most burned energy is from resting metabolism. Aside from basal or resting metabolism, there are two other ways that the body burns energy each day: breaking down food and physical activity. The resting metabolic rate accounts for 60 to 80 percent of the body’s total calories burned each day and physical activity accounts for about 10 to 30 percent, followed by digestion, which burns about 10 percent.
- Metabolism can vary a lot between people, but researchers don’t know why. Researchers have found a couple of predictors of how fast a person’s metabolism will be, including the amount of lean muscle and fat tissue in the body, age and genetics. Gender also plays a role. Women burn fewer calories than comparably-sized men.
- Getting older slows down the metabolism, meaning one burns fewer calories at rest when they’re 60, for example, than when they’re 20.
- Metabolism can’t really be sped up for weight loss – it’s actually very difficult to do. While certain foods like coffee, chili and other spices may speed up the basal metabolic rate, the change is too negligible and short-lived to have any kind of impact on the waistline. Building more muscles is marginally more helpful because the more lean muscle one has, and the less fat, the higher the metabolic rate because muscles uses a lot more energy than fat while at rest.
- Drastic weight loss programs can actually slow down one's metabolism. Researchers have found that a phenomenon called “metabolic adaptation” occurs as people lose weight because their basal or resting metabolic rate – the energy used for basic functioning when the body is at rest actually slows down to a greater degree than would be expected from weight loss, Vox reports.
- Researchers don’t understand why this metabolic slowdown happens, but one explanation is evolution, periods in history when the human race had to deal with periods of under nutrition may have resulted in the body storing energy instead of burning it when deprived of food. This may explain the inability to keep the weight off as a means for the body to defend against periods of under nutrition.
- A slower metabolism doesn’t mean it isn’t possible to keep the weight off. The key to losing weight and keeping it off is to make lifestyle changes that are lasting, and by viewing those changes as necessary to keeping the disease of obesity under control.
- And a fun fact about metabolism: hummingbirds have the fastest metabolism in the animal kingdom, because of their extremely fast 60 to 80 wing flaps per second. Even though they consume mostly sugar, the rapid wing movement burns it right off.
