Iron deficiencies can slow down your metabolism. Do you know what’s got plenty of it? Lean meat. Eating three to four daily servings of iron-rich foods will help keep your inner furnace burning. Fortified cereals, dried fruit, and dark leafy greens will get you on your way to meeting your iron goals, but lean meat—with its high muscle-building protein content—will be doubly useful in revving up your metabolism.
To get why, you have to understand a bit of the science behind metabolism. Your metabolic rate is essentially the speed at which your body expends energy, and it depends on many different factors. Your age, weight, health history, organ function, oxygen capacity, and even your height can all influence how many calories you burn during exercise, but also (and more importantly) during sedentary times of day.
Muscle burns more calories than fat. So will building more muscle not boost your metabolism? Yes, but only by a small amount. Most regular exercisers only gain a few pounds (kilograms) of muscle. That is not enough to make a big difference in the number of calories you burn. Plus, when not in active use, muscles burn very few calories. Most of the time, your brain, heart, kidneys, liver, and lungs account for most of your metabolism.
Experts say weight training is the best way to crank up your resting metabolic rate. "As you get older, your resting metabolic rate drops, but weight training can rev it right back up again: A pound of muscle burns up to nine times the calories a pound of fat does," explains fitness expert Westcott. In fact, a woman who weighs 130 pounds and is muscular burns more calories than a sedentary 120-pound woman of the same height. Regular strength training can increase your resting metabolic rate anywhere from 6.8 to 7.8 percent. (That means that if you weigh 120 pounds, you could burn around 100 more calories a day, even when you're just watching TV.)
Yeah, yeah, it has zero calories, but drinking diet soda may yet play havoc with your goal of having a flat belly. Research published in the journal Trends in Endocrinology & Metabolism shows that artificially sweetened beverages may screw up the body’s normal metabolic response to sugar, actually increasing appetite! Increasingly, diet drinks are being linked to weight gain, metabolic syndrome and a host of other ills. (Find out what happens to your body when you give up soda.) Best to give them a wide berth. But if you really crave something sweet…
Cardio improves definition and burns the fat that covers your muscles, especially belly fat. Combining regular aerobic exercise with strength training will give you the slimming effect you've been going for. After all, toning without cardio is like building a house on a weak foundation. Blast calories with these 20-minute cardio workouts from celebrity trainer Jackie Warner.
For nutritionist Lisa Jubilee, one of the best and cheapest ways to give your metabolism a jolt is to drink water (she suggests 20 to 32 ounces) shortly after waking. Why? During sleep, your body’s metabolic function slows down, and unless you wake up in the middle of the night to swig some water, you’re not taking in any fluids. Jubilee suggests completely rehydrating before stressing your body with any other food or drink. “My clients who have implemented this report less bloating, more energy and a smaller appetite,” she says. Her motto for getting your inner furnace stoked and ready for the day: “Rehydrate, then caffeinate!”
Plus, strength workouts have an additional metabolism-boosting benefit. Because this type of anaerobic training involves breaking down and building back up of muscle tissue, the body needs to burn more calories in the 24 to 48 hours after each session—a phenomenon known as excess post-exercise oxygen consumption, EPOC, or, informally, "afterburn.” Researchers, however, are currently debating how intense that afterburn really is.
Most of us choose one time of day to get our exercise in—whether that’s first thing in the morning or right after work. Though having a routine is helpful, Katherine suggests incorporating physical activity into both morning and night. For example, if you typically only exercise in the morning, then do a little something in the afternoon or early evening to bring the heart rate back up for a bit. “Evening exercisers can do the same thing in the morning,” she says. “Ten to 15 minutes of some activity in the morning will jump-start your metabolism for the day and will do a world of good.”
It’s like butter that grows on trees. But instead of the cholesterol, trans fats, and saturated fats in real butter, avocado contains metabolism-enhancing monounsaturated fat. And that’s not all. Each creamy fruit is also packed with fiber and free-radical-killing antioxidants. Free radicals are destructive rogue oxygen molecules—natural byproducts of metabolism—that trigger various chain reactions in the body that destroy cells and DNA, causing all kinds of health problems. Antioxidants in fresh fruits and vegetables can help neutralize some free radicals, but they can’t reach the mitochondria—the base camp for the free radical army—and that’s a problem. When your mitochondria aren’t working properly, your metabolism runs less efficiently. Enter: Avocado. A 2015 study found that monounsaturated-rich oil pressed from the fruit can help mitochondria become more resilient. Researchers say the results jive with low-disease rates in Mediterranean countries where olive oil—nutritionally similar to the avocado—is a diet staple.
If you have a fast metabolism, it means your body burns more calories during rest as well as during activity. It also means you’ll need to take in more calories to maintain your weight. As expected, someone with a low metabolism is the opposite – meaning they burn fewer calories at rest and during activity, and have to eat less if they want to avoid weight gain, the school says.
Activity. Aerobic exercise helps you burn calories, and strengthening exercises (resistance training) can help you build and maintain muscle mass. Having more muscle causes you to burn more calories even while at rest (your resting metabolic rate). Keep in mind that building more muscle to burn calories is much more difficult than burning calories through aerobic activities.
It sounds counterintuitive; why would you eat continually if you wanted to lose weight? But eating five to six mini meals rather than three larger meals every day keeps your metabolism humming 24/7. "It will also prevent you from going without food so long that you become so hungry you overeat," says Peeke. Try not to let more than four hours elapse between meals and make sure each meal includes protein, for an extra metabolic boost. If you eat a high-fiber breakfast of cereal and fruit first thing, for example, have a midmorning snack, such as yogurt and fruit; lunch (try four ounces of chicken or fish on top of a leafy green salad); another snack, like a banana and a piece of low-fat cheese, in the late afternoon; and a light dinner (think four to six ounces of turkey, salmon, or another lean source of protein with steamed veggies).
Move more and faster. Research shows high intensity interval training (where you go all out for 30 to 60 seconds, slowing down for a couple of minutes, and repeating) coupled with strength training is an excellent way to make new, improved mitochondria. Strength training builds muscle and creates more mitochondria, while interval training improves mitochondrial function and how quickly they burn oxygen and calories. You can learn more about an effective exercise plan here.
This antioxidant-rich, traditional Chinese tea not only helps keep cholesterol levels in check and aids digestion, it can also help rev up your metabolism. Like green tea, oolong is packed with catechins, which boost weight loss efforts by improving the body’s ability to metabolize fat. A study in the Chinese Journal of Integrative Medicine found that participants who regularly sipped oolong tea lost six pounds over the course of six weeks.
Eat six small meals a day to avoid blood-sugar spikes and minimize urges to binge. Try to schedule meals at the same time each day. If you feed yourself well throughout the day, you'll learn to understand when your body truly needs food. You can't starve yourself and expect to make good choices at the next meal. Need a few healthy lunch ideas? Check out these top food swaps from a nutritionist.
While nutritionists agree that there is no magic food to revving up your metabolism, getting enough exercise, especially the right kind of exercise, is key. Experts suggest strength training two or three times to build lean muscle mass. “A pound of muscle burns up to nine times more calories than a pound of fat,” says nutritionist Lisa Stollman. “Lifting weights is a great way to build muscle mass.” However, the point is not just to build lean muscle mass, but to maintain it. “As we age, we start to lose muscle,” says Pincus. “Strength training not only builds muscle groups to burn more calories, but also helps preserve them and prevent loss.” Check out these other nutritionist-approved ways to speed up your metabolism.
The omega-3 fatty acids found in fish oil have been shown to increase the speed of your metabolism exponentially. According to a report from the University of Ontario, researchers found the consumption of oily fish with omega-3 can increase the fat-burning enzymes in the body and lower levels of stored fat, says Elle UK. The supplement can help you burn an extra 400 calories a day, or 25 percent of your daily calorie intake.
“Hormones dictate how our body utilizes the energy we give it,” says nutritionist Lisa Jubilee. “Between our reproductive, thyroid and growth hormones, appetite, insulin, and hunger hormone leptin and ghrelin, our bodies have to perform a tricky balancing act to keep us lean, energized and viable reproductive beings.” Those tasks have become much more difficult because of the hormone residues we consume via cage-raised foods. If you want to give your metabolism a leg up, Jubilee says, switch to organic, grass-fed, pasture-raised beef, eggs, and dairy products, thereby avoiding those nasty hormones at mealtime.