Can You Really Boost Your Metabolism? Here's What the Research Shows

Cold showers, apple cider vinegar, "eat six small meals a day": few body topics attract as many myths as metabolism. Search for how to boost metabolism and you'll mostly find listicles of home remedies — rarely a look at the actual studies behind them. We checked what nutrition, exercise and sleep can genuinely change according to research, and what's mostly a stubborn rumor.

What your body actually burns at rest

Most of your daily energy use has nothing to do with exercise. Your basal metabolic rate — the energy your body needs simply for your heartbeat, breathing, cell repair and brain activity — makes up the largest share of total energy expenditure for most people. How high it is depends heavily on your fat-free mass, mainly muscle: more muscle mass means a higher basal metabolic rate, because muscle tissue burns more energy at rest than fat tissue.

On top of that comes diet-induced thermogenesis (DIT) — the energy your body spends digesting and processing food itself. It's a smaller slice of daily expenditure, but it's the lever behind several of the studies below.

Four levers with real evidence behind them

Instead of a list of ten home remedies, we focused on four areas that actually have controlled studies behind them — including the limitations those studies themselves point out.

1. Protein has the highest thermic effect of any macronutrient

The fact that your body spends more energy digesting protein than carbohydrates or fat isn't a marketing claim — it's well documented. A 2024 systematic review confirms that protein is the macronutrient with the strongest effect on diet-induced thermogenesis, which accounts for roughly 10% of total daily energy expenditure overall.^[1] Important context: this effect concerns digesting a protein-rich meal — it doesn't turn a sluggish digestion into a calorie furnace.

2. Resistance training protects your basal metabolic rate, especially while dieting

Losing weight often means losing not just fat but muscle mass too — and with it, part of your basal metabolic rate. A controlled study with overweight participants found that those who added resistance training during a diet preserved their fat-free mass and basal metabolic rate significantly better than participants who did aerobic training instead.^[2] The effect here is less about "boosting" and more about preventing an unnecessary drop.

3. Caffeine and green tea catechins raise energy expenditure — slightly, but measurably

A classic study in the American Journal of Clinical Nutrition had participants take a green-tea-based extract over several days and measured energy expenditure over 24 hours in a metabolic chamber: expenditure rose by roughly 4% on average, an effect that went beyond the caffeine content alone.^[3] A systematic review covering 15 studies confirms positive but overall moderate effects of green tea catechins on resting energy expenditure.^[4] Four percent sounds unspectacular — and in everyday life, it is. Credible sources deliberately don't call this "fat burning," but rather a small, additive building block.

4. Sleep deprivation slows energy expenditure down — not the other way around

Here's where it gets interesting: a study published in Obesity found that morning resting metabolic rate dropped significantly after several nights of only four hours of sleep, and only normalized after recovery sleep.^[5] The researchers see this as a possible explanation for why chronic sleep deprivation is linked to weight gain. Good sleep, then, works less like a calorie booster and more like a precondition for your metabolism to function normally at all.

Common myths, checked against the evidence

Many online guides repeat the same tips without checking them against the research. A few of the most persistent claims, side by side:

Who might this be especially relevant for?

• Anyone who notices weight creeping back up after a diet (a possible sign of a reduced basal metabolic rate)
• Anyone regularly sleeping less than 6-7 hours and wondering why weight loss feels harder
• People in midlife noticing a slower metabolism as muscle mass naturally declines
• Anyone currently eating very little protein who wants to know where the untapped potential lies

How to build this into your routine

None of the four levers require a radical overhaul. Realistic steps include:

• A protein source with every main meal: eggs, quark, legumes, fish or meat instead of relying solely on carbohydrates.
• Two resistance training sessions per week: preserving muscle matters especially during calorie-deficit phases.
• One to two cups of coffee or green tea across the day: a small, additive building block — not a substitute for the basics.
• Consistent sleep times: 7 hours or more, as regularly as possible, including weekends.

Frequently asked questions about boosting metabolism

Learn more

Glow25 Collagen Plus Glow25 Balance Glow25 Collagen Original with Vitamin C Collagen types 1, 2 and 3: the differences