That’s because much of what defines your metabolism is outside of your control—age, genetics, gender.
Your body’s basal metabolic rate, estimated as resting metabolic rate (RMR), accounts for 70 percent of your metabolism. It’s the amount of energy your body burns to keep itself functioning while at rest. This is what people connect to when they talk about boosting up their metabolism.
Besides getting more physical activity during your day—which accounts for 20 to 25 percent of your metabolism, there are just a few intrusions that might boost your metabolic rate long term.
4 Ways to Speed Up Metabolism
1. Build and maintain body muscle mass
“People who have more body muscle are usually going to have a more powerful metabolism,” says Douglas White, Ph.D., associate professor in the department of nutrition, dietetics, & hospitality management at Auburn University. That’s because it takes more energy to support muscle mass in your body than it does fat.
While eating protein gives your body essential amino acids, it doesn’t build muscle mass. If you consume more protein than your body wants, it doesn’t stock it as protein, which would influence your metabolic rate. It transforms it back into glucose and fat,” says White. “That’s no distinct than what would result if you consumed carbohydrates or fat.”
2. Eat smaller meals throughout the day
Every time you eat, you give your metabolism a small boost. It’s known as the thermic effect of food (TEF) and accounts for 10 percent of your overall metabolism.
“All foods are thermogenic. They all have to be burned in your body. They produce energy in your body, so in that way, they boost your metabolism,” says Julie Metos, Ph.D., RD, associate chair, department of nutrition and integrative physiology at the University of Utah School of Medicine.
Frequency, or how regularly you eat, has been shown to enhance metabolism, says Metos, with a study showing that eating every three or four hours helps to sustain a steady TEF. “The thought is if you eat large meals and then you don’t eat for a long time, that your metabolism slows down between those eating sessions,” says Metos.
But, if you’re inclined to overeating at meals, it could work against you. “You have to balance the small metabolic effect with the behavioral effect,” says Metos.
3. Avoid late-night meals
From a metabolism viewpoint, it doesn’t matter what time of day you eat. Anytime you eat, you’re still burning calories thanks to TEF. “It’s not certain because the calories are more impactful in the evening—they give you the equivalent amount of energy—but you have less time to burn it off,” says Cheskin.
4. Drink enough water
“Water is very essential in the metabolic process, and if you don’t have adequate water you can slow down your metabolism,” says Metos, who recommends at least eight 8-ounce glasses of water every day. However, the experimental jury is still out on water’s ability to improve your metabolism. If there is any influence, it’s likely due to thermogenesis—so the water needs to be very cold.
What Doesn’t Change Metabolism
It’s dizzying how many fictitious quick metabolism “boosters” are out there. Here are some common ones that study says fall short of, or don’t make any, meaningful long-term difference in metabolism or weight loss.
TEF is also known as diet-induced thermogenesis, but that doesn’t mean a special diet helps you burn more calories. There are not really any distinct foods that boost your metabolism significantly outside of the thermic effects, says Metos.
As for the claim that some foods, like grapefruit, burn more fat than others? “No, there aren’t any,” says Metos. “Improving metabolism would burn everything—carbohydrates, protein, and fat. It’s hard to partly burn one thing over the other.”
The main cause grapefruit and other citrus fruits keep making the myth list is simple, says Cheskin: “It makes you eat less because it leaves a sour taste in your mouth.”
Only a few things in food are known to have a small additional effect on metabolic rate—caffeine, catechins (a chemical compound found in green and white teas), and capsaicin (a compound found in spicy foods, such as chili peppers). These provide a 4 to 5 percent increase in metabolic rate, according to a study issued in the International Journal of Obesity. But their influence is short-lived and not long-term, says Cheskin. “It’s not going to make a distinction between losing 50 pounds and gaining 50 pounds. But if you like green tea, go for it.”
To get any constant metabolic increase you would have to eat these compounds around the clock. In the case of too much caffeine, that could have harmful effects on your health, says Metos, including disturbing your sleep, developing anxiety, and increasing your blood pressure.
The other difficulty is the extra calories you can consume depending on which foods you choose, says Cheskin. “If you’re going to have your caffeine in regular soda, sports drinks, or sweet coffee drinks, that’s not great for weight control.”
Focusing on healthy eating patterns matters more. It’s not going to be the mysterious answer for you to include one of these things without making other changes.
Diets high in protein or fat
Diets abundant in fat or protein don’t raise or lower your metabolic rate, says Metos. What they may do is make you feel full, which in turn decreases the number of calories you consume.
Gluten only improves your metabolic rate if you have Celiac disease, says Cheskin. People with the Celiac disease can’t process gluten, a protein found in wheat and other grains. It degrades their small intestine making it weak to help absorb nutrients into the body.
Drastically decreasing calories, by fasting or starving yourself, slows down your metabolism. Not only are you dropping out on the thermic effect of food, but your body goes into maintenance mode, says Metos.
Your body will burn whatsoever is available to it. If there’s nothing available to it, it will burn what’s onboard, which are your muscles and the glucose in your blood or the glycogen, which is the glucose in your liver.
Intermittent fasting might play a part in weight loss, but it does nothing to increase metabolism, says Cheskin. Your metabolism bounces once you eat, but it’s not a recipe for long-term weight loss because it’s generally not endurable.
“You can increase your metabolic health and enhance your metabolism overall by eating regularly and not yo-yo dieting,” says Metos. “People who have a routine (eating) pattern tend to maintain their metabolism as opposed to people who go long periods of time without eating, and then overeat, and then decide they’re going to fast for a day. It’s better to have an even-keeled eating pattern.”
Your metabolism is at its lowest point in a 24-hour period when you’re asleep. Even if you stay up and think you’ll burn more calories, you’re probably staying up and eating to make up for it.
Even though sleep decreases your metabolism, not getting enough sleep does more harm than good when it comes to losing or maintaining weight.
Being more relaxed makes your body function better and makes you less prone to desire foods that you don’t need. What we do know is that people who get enough sleep or more sleep tend to have reduced body weight than people who don’t get enough sleep.