You step on the scale only to see that it hasn’t moved at all. Or you get into the afternoon and just can’t stop yawning. What is causing your system to slow down? In the process of searching for answers, you’ll likely comes across experts and celebrities blaming weight stagnation (aka weight gain) and low energy on slow metabolism.
But what exactly is metabolism? If yours is slow, is there anything that can be done to speed it back up? And is faster always better?
Chances are you’ve asked yourself these questions in your quest to move toward better health, especially as you age. Unfortunately, it can be hard to get straight answers about metabolism, in part because it’s a very complicated bodily process that affects so much more than just our weight and energy levels. In fact, our metabolism affects every single process in our bodies.
You may see celebrities and health experts proclaiming that they’ve found the newest and best way to boost metabolism, but the truth is that keeping your metabolism running at a healthy level requires a holistic approach rather than a quick fix.
HealthyWay talked to experts about the misunderstandings around metabolism and how to naturally give your metabolism a boost. Here’s what they had to say.
What is metabolism, anyway?
Simply put, metabolism is the process by which your body converts food into energy.
That sounds fairly simple, right? It is, until you realize that every single system in your body relies on metabolism to keep functioning. When you eat, your body breaks down the calories in your food to fuel your bodily processes. This energy isn’t just directed at keeping you going through a long work day—in fact, most of it is expended on critical bodily functions like breathing, restoring cells, and regulating your hormones.
The amount of energy that your body needs to maintain all these functions is called your basal metabolic rate or BMR. Put a bit differently, your basal metabolic rate tells you how many calories you would need to survive if you were at rest (think, laying in bed) for 24 hours. BMR is what most people are talking about when they refer to metabolism.
Another term frequently used in discussing metabolism is resting metabolic rate or RMR, which is similar to BMR, but is less restrictive when it comes to how it’s measured. According to the American Council on Exercise, a formal measure of a person’s RMR does not require that they sleep overnight at a testing facility, for example.
And while you might think that you use the most energy when you’re moving around and exercising, the truth is that your basal metabolic rate—the energy needed just for critical functions—accounts for about 70 percent of your energy usage each day. That’s important to know since it’s relatively easy to go to the gym and burn a few hundred more calories, but tougher to increase the amount of energy required to keep your body functioning, which is what it takes to boost your BMR.
The food that your body metabolizes quickly is used to fuel your body functions. Food that is not metabolized before you eat again is more likely to be stored as fat, Gupta says.
“The quicker your metabolism, the quicker you are able to make fuel of the nutrients you ingest and the less likely it is to become fat,” he explains. “If you don’t metabolize the food you have eaten from your last meal before eating another, you will have too many calories and much of what you eat will be stored for future energy.”
So, if your body takes longer to convert food into fuel (that is, if you have a slower metabolism), you are more likely to be consuming excess food that will wind up being stored as fat rather than being burned off in the course of daily activity.
What affects your metabolic rate?
We often hear talk about fast or slow metabolisms, but the truth is that there is no ideal metabolism. One study published in the journal Medicine and Science of Sports and Exercise concluded, “No single value for [resting metabolic rate] is appropriate for all adults.” Rather, metabolic rate is determined by various genetic and lifestyle factors.
There are many different (and complicated!) equations for calculating basal metabolic rate. Although they boast varying degrees of accuracy, a study published in the International Journal of Obesity found that a few specific factors that have the biggest effect on basal metabolic rate.
According to the study, body composition has the largest impact on a person’s BMR. People with more fat-free mass (that is, those who have more muscle) are more likely to have a higher metabolic rate. Since men have more muscle than women in general, they typically have a higher metabolic rate. (If you’ve ever noticed that your husband or brother can eat tons of food and never change shape, science says you’re onto something.) As people age, their metabolism tends to slow down, more quickly in men than women, the study found.
Again, this has to do with muscle mass and the fact that muscle generally decreases with age.
Does a higher metabolism help you lose weight?
In popular culture, we talk about weight and metabolism as if the two go hand in hand, but that understanding isn’t entirely accurate. There is a connection between metabolism and weight, but it’s a pretty complicated one, experts say.
Remember how Gupta explained that food that is metabolized quickly is burned as fuel, whereas excess food (calories that are not burned before we eat again) is stored as fat? In this way, yes, having a slower metabolism can lead to having more body fat.
However, weight gain (or the inability to lose weight) is affected more by what we eat, how much we eat, and how much exercise we get than by our basal metabolic rate, experts say.
“Contrary to common belief, a slow metabolism is rarely the cause of excess weight gain,” experts at the Mayo Clinic write in an article on the relationship between metabolism and weight loss. “Although your metabolism influences your body’s basic energy needs, how much you eat and drink along with how much physical activity you get are the things that ultimately determine your weight.”
Basically, we need to eat in line with our unique metabolisms. Since men generally have a higher metabolisms, their daily recommended caloric intake is higher. If a woman (who will generally have a lower metabolism) ate the same amount of calories recommended for a man, she might gain weight, but the reason for her weight gain would be overeating based on her needs, rather than a deficiency when it comes to her metabolism.
That shift in thinking is subtle but important for people who are trying to lose weight. A slower metabolism doesn’t prevent you from losing weight, it just means you need to eat fewer calories.
“While it is true that some people seem to be able to lose weight more quickly and more easily than others, everyone loses weight when they burn up more calories than they eat,” the Mayo Clinic experts write. “To lose weight, you need to create an energy deficit by eating fewer calories or increasing the number of calories you burn through physical activity or both.”
At the same time, if your metabolism is higher, your body may need more calories each day, and therefore you can expect to consume more food without gaining weight because the calories you consume and burn will not be stored as fat.
Does metabolism slow down with age?
Many people are concerned that they will gain weight because their metabolism will slow down as they get older. Women, in particular, may worry that when they reach their forties they will suddenly have slower metabolisms that will thwart their health and fitness goals.
And yes, it’s true that metabolism decreases with age. This slowing of BMR is caused by a combination of lifestyle and physiological effects.
“As we age, we have a tendency to be less active and we also have less muscle mass,” Gupta explains. “As a result, our metabolism does slow down. In order to counteract this, we need to maintain our muscle mass through exercise, which becomes a greater struggle as we age because muscles no longer respond as quickly as they did when we were younger.”
This is the biggest key to boosting your metabolism.
If you’re looking for a single thing you can do to boost your metabolism, this is it: Develop more lean muscle, particularly through weightlifting exercise.
“The more muscle mass a person has, the quicker their metabolism,” Gupta says. That’s because lean muscle requires more energy than fat does. If you add lean muscle to your body, your basal metabolic rate increases and your body burns more calories in order to sustain that muscle, which accounts for the assertion (in the International Journal of Obesity study, cited above) that people with more lean muscle have higher metabolic rates.
Robert S. Herbst, a personal trainer and former Olympic official, explains further.
“Having more muscle means having a higher metabolism because muscle is metabolically active,” he says. “It burns energy and gives us body heat. Having more muscle means burning more calories even when you are at rest, just like a six cylinder car burns more gas than a four cylinder one when stopped at a red light.”
In addition to helping you develop more lean muscle, doing weightlifting exercises further boosts your metabolism even when you’re in post-workout recovery mode.
“Weight lifting increases your metabolism because it causes your body to spend energy to recover from the workout,” Herbst explains. “During weight training, the muscle fibers incur microtears. To recover, the body repairs these tears, sending protein to the muscle and removing waste products. All this takes energy.”
In fact, your metabolic rate is raised for up to 72 hours after a weightlifting session while your body expends extra energy to repair the muscle fibers that were damaged during the process, rebuilding them stronger.
To get this benefit, Herbst recommends doing exercises that engage major muscle groups, like squats, lunges, deadlifts, and bench presses. For women, these same exercises are especially beneficial because they also strengthen bones, helping to prevent osteoporosis as well.
The Power of a Good Night’s Sleep
Hitting the gym can be daunting, but it’s an important way to stay healthy and increase your metabolism. This next suggestion is a bit more tame, but still important: Get more sleep.
One study found that sleep disruptions—like shift work, not getting enough sleep, or having sleep apnea—can significantly disrupt metabolism. More studies need to be conducted in order for scientists to pinpoint exactly why this is, but suffice it to say that getting a solid eight hours of sleep is important to keeping your body functioning at its best.
Eat this every day.
Another natural way to boost your metabolism is to make sure you’re getting enough protein, says Anna Morrison, a family nurse practitioner and co-founder of the No BS Supplements Company.
“Protein is the foundation of creating muscle,” she says. We’ve already established that having more muscle is essential for boosting metabolism, and eating protein (especially after a workout) can help you build that muscle.
Morrison points out that it’s important to change protein sources regularly to keep your digestive system healthy and ensure that the protein you’re eating is being metabolized effectively.
“Changing up your protein sources is one of the best ways to increase your metabolism, especially if you’re over 40,” she says. Spend a few days a week getting your protein from beans, lentils, and other plant sources. Then switch to animal proteins like meat and eggs. Morrison points out that this variety is great for overall health.
“Varying your protein source is also a great way to get a well-rounded diet,” she says.
Definitely don’t do this.
If you’re looking to boost your metabolism, it’s important to eat regularly.
“While skipping a meal might seem like a good way to lose weight, it’s actually detrimental to your metabolism,” says Richard Aponte, former personal trainer and head of product development at Myokem Supplements. “Your body will actually assume that you are starving and conserve energy by slowing down your metabolism.”
The most common meal that people skip is breakfast. Mornings can be hectic, but take time to grab a breakfast that is full of lean protein, healthy fat, and complex carbohydrates, Aponte says.
Speaking of healthy fats, Aponte points out that eating plenty of Omega-3 fatty acids is another way to boost your metabolism. These fats, found in seafoods and plant-based sources like flax, can help send signals to your brain that you have eaten enough, keeping you from ingesting so much food that your metabolism can’t keep up.
In many ways, your metabolic rate is determined by things like your genetics, sex, and size. However, taking reasonable steps like incorporating weight training, making time for sleep, and eating intentionally can boost your metabolism and help you look and feel your best.