Skip to content

26 Worst Habits Slowing Your Metabolism, Says Science

Stop sabotaging your fat-burning machine.

Exercise and eating right aren't the only two things that will help you blast fat. Your body's metabolism—or its ability to burn calories and convert them to energy—also plays a major role in weight loss. The more efficient your metabolism is, the easier it will be for you to lose weight. And if the scale isn't tipping in your favor despite all your hard work, your metabolism might be on the slower side.

Before you can boost your metabolism, you have to identify the daily habits you're undertaking that are likely to blame for slowing it down. Below, find out which metabolism-sabotaging mistakes you're making and a few of our best tips to reverse the damage. Rid yourself of these mistakes, and to really keep yourself on track, try these Eating Habits to Lose Abdominal Fat As You Age, Say Dietitians.

You're Not Eating Enough

Woman not eating enough

While, yes, the only way to drop weight is by burning fewer calories than you consume, but that doesn't mean you should be depriving your body of food.

"In an attempt for quick, noticeable weight loss, many people wrongfully believe that eating as few calories as possible is the best solution," explains Lisa Moskovitz, RD, CDN. "Not only can this lead to numerous nutritional deficiencies as the body is getting less food overall, it can actually have the opposite effect on weight loss," she elaborates. When you take in too few calories, it forces your body into starvation mode, which causes your body to use muscle mass as fuel. It also decreases the rate of your metabolism and calorie burn to conserve energy.

Eat This! Tip: You don't have to cut calories like crazy. Just check out our exclusive report: 30 Ways to Eat More But Weigh Less.

You Always Unwind With a Drink

men drinking beer at a bar

It's time to find another way to relax and unwind after a stressful day at work. While drinking in moderation every so often won't do too much harm to your waistline, making it a habit can slow down your metabolic rate. Why?

"When a person drinks, acetaldehyde (a highly toxic substance) is formed," says Los Angeles-based nutritionist Seth Santoro, CHHC. "The body spends time trying to detoxify itself rather than burn calories." Researchers have found that boozing can decrease the body's fat-burning ability by up to 73%! Even worse, Santoro adds that drinking alcohol can impair protein synthesis and anabolic (muscle-building) hormones, which can stifle your tone-up goals.

You Skimp On Protein

chef salad

Muscle is more metabolically active than fat. That means muscle not only makes you look toned, but it also helps you burn more calories—whether you're working out or just lounging around watching a movie. While you'll have to do resistance training to build muscle to begin with, if you don't pair your gym time with consumption of enough protein, your body won't be able to build muscle mass.

Eat This! Tip: Protein needs differ by individual, but consuming 0.8 to 1 gram of protein per kilogram of body weight each day is typically sufficient to fuel weight loss, says Leah Kaufman, MS, RD, CDN, a New York City-based Dietitian. For a 130-pound (58 kilogram) person, that would equal between 46 and 58 grams of protein per day. Looking for ways to eat more of the muscle-building macro? Check out these 25 Ways to Increase Your Protein Intake.

You Go to Bed Late and Wake Up Early

Alarm clock ringing,annoyed woman waking up in early morning for work.Sleeping disorder

Even if you're eating right and working out, being chronically sleep-deprived may be the reason your metabolism is slowing down. "A lack of sleep can cause several metabolic problems," says Santoro. "It can cause you to burn fewer calories, lack appetite control and experience an increase in cortisol levels, a hormone which stores fat."

Eat This! Tip: If you're looking to get into a better sleep routine, look no further than The Sleep Diet: 7 Habits of Highly-Rested People.

You Sit All Day

businesswoman eating a sandwich at her desk in her office

Our desk jobs are making us fat—and it's not just because of those office cupcakes. When you sit all day at work, your body isn't engaging or using your muscles as much as it would be if your were walking around. Because we aren't using our bodies, we begin to lose muscle mass and our resting metabolism slows.

Eat This! Tip: You don't have to give your two weeks' notice to rev up your metabolism. Simply getting up from your chair and taking a two-minute walk once every hour can do the trick, says Albert R. Matheny IV, RD, CSCS, Co-Founder of SoHo Strength Lab. He sites a recent study which found these short bursts of walking helped to maintain stable insulin levels, which means your body will be able to use calories for energy rather than just store them as fat. Set your phone alarm to go off once every hour so you don't forget to take a break.

You Drink Your Water Plain

water glasses

Water is delicious on its own, but if you're only drinking it plain, you could be missing out on some serious metabolism-boosting benefits. To get even more bang for your hydrating buck, warm up your water and steep a green tea bag in it. Researchers find that this leaf is particularly efficient at blasting flab thanks to its concentration of catechins: a group of antioxidative compounds that fry adipose tissue by revving the metabolism, increasing the release of flab from fat cells, then speeding up the liver's fat-burning capacity.

You're Constantly On Edge

stressed woman

Whether it's due to a traffic jam, your kids' overlapping sports schedules, or a huge project due at work, stress can be a huge weight on your shoulders—as well as the reason you've packed a huge amount of weight onto your hips. According to research published in the journal Biological Psychiatry, stress can make the body metabolize food more slowly and can cause sleep disturbances. (And as we mentioned above, when you don't sleep well, your metabolism suffers.)

Eat This! Tip: Looking to take a breather and ease away the stress? Check out our report: How to Relax So Healthy Eating Works.

You Nap Frequently

girl napping

While taking a nap once in a while is fine, doing it every day may be slowing down your metabolism. University of Colorado at Boulder researchers found that people burned 52 to 59 fewer calories when they slept during the day than they did while catching their zzz's in the evening. The researchers believe this mess-up in metabolism is likely because the flipped sleep schedule messed with participants' natural circadian rhythms, the body's internal clock that plays a major role in metabolism function.

Your First Drink of the Day is Coffee

hot coffee in white mug with beans

We're not knocking coffee. We're just saying you shouldn't wait an hour or so after waking to hit up your local barista for your first drink of the day. According to New York-based dietician Lisa Jubilee, MS, CDN, one of the easiest ways to give your metabolism a jolt is to drink 2 cups of water shortly after waking. Why? During sleep, your body's metabolic function slows, and your body just went around eight hours without fluids. Jubilee suggests 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

You're Following A Strict Low-Carb Diet

Cut carbs

Yes, low-carb diets are more effective for short-term weight loss than low-fat diets, but that doesn't mean you should take it to the extreme. Carbs actually help your body metabolize protein and use it to build muscle because they're a source of energy. Without carbs, your muscles can't grow. With less muscle mass, you'll burn fewer calories at rest. But that's not all. With your muscles starved of energy, you won't be able to exercise as intensely as you otherwise would. And that means fewer calories burned while active.

Eat This! Tip: Have a serving of oatmeal, half a sweet potato, or cup of brown rice prior to working out to give your muscles the fuel they need.

You Snack On Chips Instead of Nuts

potato chips

Chips are a standard snack, but if they're your go-to you might be dampening your metabolism's efficiency. Chips are largely devoid of nutrients, giving nothing to your hungry body except for something to chew. Instead, snack on a handful of nuts. The polyunsaturated fatty acids (PUFAs) found in walnuts have been found to enhance the activity of certain genes that control fat burning, meaning that a nutty snacker may burn more calories throughout the day than one who grabs another type of lower cal snack, according to a review published in The American Journal of Clinical Nutrition.

You Don't Consume Enough Calcium

leafy greens kale spinach

Calcium plays a key role in regulating the way your body metabolizes food. Specifically, it determines whether you burn calories or sport them as a flat tire around your midsection. According to research conducted at the Nutrition Institute at the University of Tennessee at Knoxville, a diet that's high in calcium could help you burn more fat.

Eat This! Tip: While dairy is a great source of calcium, it's not the only way to get the mineral into your diet. Kale is among one of these 20 Calcium-Rich Foods That Aren't Dairy.

You Don't Refuel After Workouts

Older male runner eating protein bar

You may not feel hungry after sweating it out, but that doesn't mean you shouldn't eat a snack. Pumping iron is meant to help your muscles grow, but to do that, your body actually breaks down muscle fibers first. After breaking down muscle fibers, your body repairs and replaces these damaged fibers to form new, stronger muscle protein strands. To repair, your body needs fuel. And that's why eating the right mix of nutrients within an hour after you finish your sweat sesh will help your muscles recover properly, which is essential for increasing metabolism-boosting lean muscle mass.

You Missed Out on Probiotics

Bowl of greek yogurt

Yet another reason you should grab that Greek yogurt: The good bacteria in probiotic foods can help improve your immune system, increase fat burn, and ramp up your metabolism, according to a 2015 review published in Diabetes & Metabolism Journal.

And You Don't Know About Prebiotics

Bananas on a tray

In order for the good gut bacteria, probiotics, to do their job properly, they need a source of fuel. Unfortunately, many Americans aren't eating foods that contain this fuel, which happens to be fiber. That's because we eat many refined carbs that have their nutrients and fibers stripped from them and fewer high-fiber foods.

Eat This! Tip: You can read up about prebiotics and some of the best sources in our exclusive report: Prebiotics: 15 Foods For Your Probiotic Efforts.

You Don't See The Sun


Since most of us are glued to our desks, we rarely see the sun. And when we do, we often put sunscreen on. If this sounds like it happens to you, you may be suffering from a Vitamin D deficiency—and your metabolism could be taking a hit. That's because Vitamin D is essential for preserving metabolism-revving muscle tissue, according to a review in the journal Therapeutic Advances in Chronic Disease.

Eat This! Tip: You can get Vitamin D from your diet or from the sun. Diet-wise, a 3.5-ounce serving of wild salmon provides 90 percent of your recommended daily value (400 IU) of the vitamin while 2 eggs provide 22 percent. Additionally, exposing your full torso to the sun for 30 minutes produces approximately 10,000 IU.

You Don't Have an Eating Schedule

late night snacking

You may have a busy work schedule, but don't let that get in the way of your eating schedule. A 2012 Hebrew University study found that when mice were fed high-fat foods sporadically, they gained more weight than mice that ate a similar diet on a regular schedule. Experts suspect that eating at the same times every day trains the body to burn more calories between meals.

You Always Opt for Conventional Foods

grocery store

Among the 20 Foods You Should Always Splurge On are the organic versions of pesticide-ridden produce. That's because a recent Canadian study found that chemicals in pesticides, called organochlorines, can mess with your body's energy-burning process and make it more difficult to lose weight. The researchers found that dieters who ate the most toxins experienced a greater-than-normal dip in metabolism and had a harder time losing weight. Experts, like Dr. Whitney S. Goldner of the University of Nebraska Medical Center, note that a growing body of evidence supports a link between exposure to pesticides and thyroid problems. (The thyroid is a gland in your neck that regulates your metabolism.)

You Buy Sea Salt

Sea salt in a bowl

More on your thyroid: this metabolism-regulating gland needs a specific micronutrient to function: iodine. If you don't have enough iodine, your thyroid is unable to produce thyroid hormones, and your metabolism can grind to a screeching halt. The good news: most table salt is iodized. The bad news: if you like fancy sea salt, you're likely not getting enough iodine in your diet.

You End Every Meal With a Sweet

ice cream

No, you don't need to finish every meal with a sugary treat. When you do, your blood glucose levels spike and the excess sugar your body doesn't need for energy is very quickly absorbed into your system and stored as fat. Both of these mechanisms put the brakes on your metabolism.

Eat This! Tip: Slash your intake of the sweet stuff with these 30 Easy Ways to Stop Eating So Much Sugar. And if you need a little sweetness, try munching on berries. Because they typically have an equal amount of fiber as sugar, your blood glucose levels won't spike as much after eating them compared to if you had fiber-free candy.

You Only Eat White Carbs

slices white bread on plate

Pizza, pasta, crackers, chips—you name it. Those foods are found in most Americans' diets. The issue here is that they're all made with refined carbs. Refined carbs are stripped of their fiber, a macronutrient that our body has to work hard to digest. Because it requires more energy to break down, it forces our body to increase its metabolism. So when you eat too many white, refined carbs, and too few complex carbs that have their fiber intact, you're left with a slower metabolism.

You Eat Mostly Packaged Foods


Packaged foods are riddled with preservatives and additives to extend their shelf-life. (For example, many of General Mills' cereals contain BHT: a petroleum-derived synthetic preservative that the company is in the process of removing from their products.) This helps big food companies rake in the dough, but it also makes you pack dough onto your belly. Studies show that mice that have had sustained exposure to chemical preservatives develop significant abdominal weight gain, early insulin resistance, and type 2 diabetes—three symptoms of metabolic disease. Limiting your exposure to dietary toxins and processed foods will help keep your metabolism revved.

Your Workouts Are Too Long

Tired woman at gym struggling to finish treadmill workout

Contrary to what you might think, longer runs don't always equate to more weight loss. In fact, the shortest workouts might confer the most benefits to those looking to lose weight. Australian researchers recently found that shorter duration workouts at a higher intensity, also known as High-Intensity Interval Training (or HIIT), helped women lose more weight than long, steady cardio workouts. According to their study, women who performed a 20-minute HIIT workout three times per week shed nearly 6 pounds more than those who exercised for 40 minutes three times a week at a steady pace. Why? The researchers explain that while HIIT is of shorter duration than a regular cardio workout, it results in greater post-exercise oxygen consumption, meaning that you continue burning calories (and boost your metabolism) for a longer period of time afterward.

You Run on Caffeine

drinking coffee

Even though some studies have found that drinking caffeine in the AM can boost your metabolism, that doesn't mean you should be drinking it all day long. Not only will caffeine late in the day interrupt your ability to fall asleep (and sleep is essential to a fully-functioning metabolism), but nutritionist Amy Shapiro MS, RD, CDN, also says that guzzling caffeinated drinks will stifle your appetite. Caffeine is a natural appetite suppressant. If you're constantly drinking it, you may not eat enough during the day. "Not eating enough throughout the day can make your metabolism sluggish," Shapiro says. "By the time you eat dinner, instead of immediately using that food for energy, your body is aggressively storing it as fat, just in case it will be deprived again."

You Keep Your Bedroom Warm

Hand turning a home thermostat knob to set temperature on energy saving mode

Turn down your thermostat. Researchers at the National Institutes of Health found that participants who slept in bedrooms set to a cool to 66°F for a month doubled the amount of brown adipose cells. These brown tissue is a type of fat that burns calories rather than stores them. "Brown fat becomes more active in cooler temperatures to help keep us warm," explains Aaron Cypess, MD, an endocrinologist at the NIH. The take-home? Sleeping in cooler temps is going to help to stoke your metabolism. So chill out to get lean.

You Don't Carry A Water Bottle With You


Water is an essential component of hundreds of metabolic reactions. If you don't drink enough water and let your body become dehydrated, you automatically set yourself up for a slower metabolism. By simply drinking about 14 ounces of water, you can briefly increase your metabolic rate by 30 percent, according to a study published in the Journal of Clinical Endocrinology and Metabolism. That's why a portable water bottle is one of our 21 Tools That Help You Blast Fat and Lose Weight.

Olivia Tarantino
Olivia Tarantino is the Managing Editor of Eat This, Not That!, specializing in nutrition, health, and food product coverage. Read more about Olivia
Filed Under