Can You Boost Your Metabolism? The Facts vs. the Myths

When it comes to weight loss, the basic principle is simple: eat fewer calories than you burn. But what if your metabolism seems to move at snail speed?

Fortunately, your metabolism isn’t fixed: it’s incredibly dynamic and adaptive. Your metabolic rate even fluctuates throughout the day and is shaped by various lifestyle factors. 

However, there’s plenty of misinformation about metabolism, making it hard to separate fact from fiction. In this article, we’ll explain what metabolism really is, debunk common myths, and share science-backed strategies to boost your metabolic rate.

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What is metabolism?

Metabolism encompasses all the chemical processes in your body that sustain life. These processes include both those that break down nutrients and those that build tissues. One crucial role of human metabolism is the conversion of food into usable energy. 

Your metabolic rate determines how many calories you need to maintain your current body weight and can be divided into four key components:

1. Basal metabolic rate (BMR): the energy your body uses at rest for essential functions.
2. Thermic effect of food (TEF): the energy expended to digest and metabolize what you eat.
3. Exercise activity thermogenesis (EAT): the calories burned during intentional physical activity.
4. Non-exercise activity thermogenesis (NEAT): the energy used in unintentional everyday movements, from walking to fidgeting.

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Busting metabolism-boosting myths

Now that we’ve ironed out the definition of metabolism, let’s see how some common claims stack up against the science.

‍Can you really boost your metabolism by…

Eating smaller, more frequent meals? 

The idea that frequent meals rev up your metabolism is a myth. Studies show that when calorie intake is controlled, meal frequency doesn’t significantly impact weight loss. Not surprisingly, a 2011 review by Bounty and colleagues suggests minimal effects on TEF, BMR, and overall energy expenditure. That said, spreading your protein intake throughout the day may help maximize muscle gain. 

Consuming “negative-calorie” foods? 

It’s commonly claimed that certain foods, like celery, are “negative calorie.” In other words, the amount of energy used to digest and absorb these foods exceeds their calorie content – or so they say. While many fruits and vegetables are low in calories, there’s no scientific evidence behind such “negative-calorie” claims. The energy used to digest any food (i.e., TEF) never exceeds its caloric content. 

Intermittent fasting? 

No, periods of fasting do not “reset” your metabolism. A study by Maruthur and colleagues found similar weight loss outcomes in those practicing intermittent fasting and those with more regular eating patterns. In addition, a 2019 review by Lessan & Ali noted no changes in metabolic rate with fasting during Ramadan, despite decreased activity levels. 

Chilling in an ice bath? 

Although a 2022 meta-analysis reports a slight increase in energy expenditure with cold exposure, most studies had subjects at temperatures near their shivering point for two or more hours. What’s more, cold water exposure has been found to increase appetite and energy intake while hindering muscle growth. 

Taking a diet break? 

Some research suggests that taking a break from dieting to eat at maintenance calories may help preserve metabolism, though the evidence is mixed. Regardless, if a diet break helps you stay on track, then don’t hesitate to use it!

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Seven strategies to speed up your metabolism

1. End the perma-diet.

Chronic dieting is a surefire way to slow your metabolism. In a calorie deficit, your body undergoes metabolic adaptations to safeguard against starvation. As a result, what was once a calorie deficit becomes your new maintenance. To preserve your metabolism, spend more time at maintenance calories. And if the damage is already done, consider a reverse diet or weight gain phase to rebuild your metabolism. 

2. Prioritize protein.

A protein-rich diet enhances metabolism through both short-term effects on TEF and longer-term benefits for BMR. A 2021 study by Oliveira and colleagues found that individuals burned an average of 81 more calories per day when they consumed a high-protein diet compared to a calorie-matched lower protein diet. These results are likely due to protein’s high thermic effect, as your body uses 20-30% of calories from protein simply to process it. Plus, adequate protein intake helps preserve muscle during weight loss, which can help minimize metabolic adaptation. One pound of muscle contributes approximately 6 calories daily toward resting energy expenditure, compared to the measly 2 calories per pound of fat.

3. Lift weights regularly.

Resistance training is key for minimizing muscle loss and preserving metabolic rate in a calorie deficit. In addition, research by Stavres and colleagues shows that regular resistance training may enhance BMR independent of its effects on muscle mass.

4. Stay active. 

Of all components of metabolic rate, NEAT is the most variable, ranging from 100 to 800 calories daily. Such spontaneous physical activity is lowest with sedentary lifestyles and further decreases with age and in calorie deficits. To counteract reductions in NEAT, integrate more movement into your day: go for a walk, clean the house, or take the stairs at work. Consider walking desks or brief walking breaks during long sitting sessions to boost your calorie burn.

5. Strategically use cardio. 

While both high intensity and steady-state cardio can elevate metabolic rate, these effects are fairly modest. Compensatory reductions in NEAT often offset calorie burn from workouts, especially when you’re in a calorie deficit. And the more you train a particular movement pattern, the more efficient your mechanics become, leading to lower energy expenditure during cardio sessions. So if you’re using cardio for fat loss, do so conservatively and only ramp up volume when you struggle to further cut calories.

6. Get quality sleep.

Poor sleep can also lower metabolic rate by reducing spontaneous physical activity and predisposing muscle loss. A study by Nedeltcheva and colleagues found that individuals in a calorie deficit lost 60% more muscle over 2 weeks when sleeping only 5.5 hours compared to 8 hours nightly. Aim for 7-9 hours of quality zzz’s to best support your metabolism, weight goals, and wellness.

7. Reduce stress levels.

Chronic stress can decrease BMR by increasing the risk of muscle loss and by altering energy-regulating hormones. In particular, stress has been found to lower levels of metabolism-boosting hormones like thyroid hormone, leptin, and sex hormones while decreasing levels of ghrelin, a “hunger” hormone that reduces energy expenditure. To maintain a healthy metabolism, incorporate regular stress-relief, such as mindfulness, breathwork, or yoga. 

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Final thoughts: Ditch the myths, master your metabolism

Metabolism is vital for survival and plays a significant role in dieting success. While countless claims promise quick fixes to boost metabolism, most are merely myths. The best way to boost metabolism lies in the fundamentals: consuming sufficient calories, prioritizing protein, engaging in regular physical activity, ensuring quality sleep, and managing stress. These time- and lab-tested strategies are the bedrock of metabolic health and game-changers for a successful, sustainable weight loss journey.