Does Cold Increase BMR and Boost Your Metabolism?

December 19, 2025 •

4 min read

According to a 2022 meta-analysis published in BMC Biology, energy expenditure significantly increases after acute cold exposure, but it's often debated whether this directly translates to a higher basal metabolic rate (BMR). Understanding the body's thermogenic response reveals how cold activates calorie-burning mechanisms to maintain a stable core temperature.

Quick Summary

Cold exposure stimulates thermogenesis, the body's heat-producing process, which increases energy expenditure through shivering and brown fat activation. This boosts overall metabolism, but it's important to differentiate between temporary metabolic increases and a sustained change in BMR.

Key Points

Cold increases metabolism temporarily: Your body burns more calories to maintain its core temperature in a cold environment, a process known as thermogenesis.
It's not a BMR change: The spike in energy expenditure from cold exposure is part of your total daily calories burned, not a permanent increase to your basal metabolic rate (BMR).
Shivering is rapid heat generation: Involuntary muscle contractions caused by shivering can burn calories at a rate up to five times higher than at rest.
Brown fat is a key player: Non-shivering thermogenesis is powered by brown adipose tissue (BAT), which burns fat to produce heat and can be activated by cold.
Long-term exposure leads to adaptations: Regular, moderate cold exposure can increase brown fat activity and density, leading to more sustained metabolic benefits.
Safety is paramount: Implement cold exposure methods like cold showers or ice baths gradually to avoid cold shock and consult a doctor if you have health concerns.
Supports weight management: The extra calorie burn from thermogenesis and activated brown fat can be a useful adjunct to a healthy diet and exercise for managing weight.

The Science of Thermogenesis: How Cold Heats You Up

To answer the question, "Does cold increase BMR?" we need to understand the body's primary response to chilly conditions: thermogenesis. This is the process of heat production, and it plays a significant role in regulating your core temperature when exposed to cold. The body has two main strategies for thermogenesis:

Shivering Thermogenesis: This is the most visible response to cold. When your core body temperature begins to drop, your hypothalamus triggers involuntary muscle contractions, or shivering, to generate heat. This rapid, high-intensity muscle activity can significantly increase metabolic heat production, sometimes up to five times the basal metabolic rate, providing an immediate and effective warming mechanism.
Non-Shivering Thermogenesis (NST): This more subtle process generates heat without muscle movement and is primarily driven by brown adipose tissue (BAT), or brown fat. Unlike white fat, which stores energy, BAT is rich in mitochondria and burns calories, especially fatty acids, to produce heat. Cold exposure is a potent activator of BAT, and regular, mild cold exposure can increase its activity and amount.

The Difference Between BMR and Overall Energy Expenditure

While cold exposure certainly increases overall energy expenditure, it's crucial to distinguish this from a sustained increase in your basal metabolic rate (BMR). BMR is the energy your body needs to perform fundamental, life-sustaining functions at complete rest, in a thermally neutral environment, after a 12-hour fast. The temporary, cold-induced increase in metabolism is a component of your total daily energy expenditure (TDEE), not a change in the BMR baseline itself. Chronic cold exposure, however, can lead to metabolic adaptations over time.

Comparison: BMR vs. Cold-Induced Energy Expenditure


Feature	Basal Metabolic Rate (BMR)	Cold-Induced Energy Expenditure
Definition	Energy burned at complete rest, fasted, and in a neutral temperature.	Extra energy burned to generate heat in a cold environment.
Mechanism	Driven by resting bodily functions (breathing, circulation, etc.).	Primarily through thermogenesis (shivering and non-shivering).
Change	Relatively stable and influenced by long-term factors like age, gender, and muscle mass.	Temporary and highly reactive; spikes during cold exposure and decreases when warmed.
Contribution to TDEE	The largest component, accounting for 60-70% of total daily calorie needs.	A smaller, variable component that adds to daily calorie burn.
Measurement	Measured in a lab under strict conditions.	Can be measured during or after cold exposure.

The Long-Term Effects and Health Benefits

Repeated or prolonged cold exposure can lead to metabolic adaptation and potentially increase your overall resting energy expenditure, even if your underlying BMR doesn't change. Regular exposure to cold, such as through cold showers, ice baths, or exercising in cold weather, has been linked to several health benefits:

Improved Insulin Sensitivity: Cold-induced BAT activation can enhance insulin sensitivity and glucose metabolism, which helps manage blood sugar levels.
Increased Adiponectin and Irisin: Cold exposure increases the production of adiponectin, which improves insulin sensitivity, and irisin, a hormone that promotes the browning of white fat and enhances metabolic function.
Enhanced Mental Resilience: Deliberately facing the discomfort of cold exposure can strengthen your mental fortitude and resilience to stress.
Support for Weight Management: While cold exposure alone won't cause dramatic weight loss, the added calorie burn from thermogenesis and the activation of brown fat can support weight management efforts when combined with a healthy diet and exercise.

Incorporating Cold Exposure into Your Routine

For those interested in leveraging the metabolic benefits of cold, it's important to start slowly and safely. Gradual acclimation is key to avoiding cold shock.

Cold Showers: Start by ending your warm shower with 30 seconds of cold water. Gradually increase the duration and decrease the temperature as you become more comfortable.
Ice Baths: For a more intense experience, consider a controlled ice bath or cold water immersion. Experts often suggest 2-4 sessions per week, lasting 1-5 minutes each, at a temperature that is uncomfortably cold but safe.
Cooling Down: After an ice bath, allow your body to rewarm naturally rather than immediately jumping into a hot shower.
Outdoor Exercise: Regular exercise in cold weather can amplify the thermogenic effect and combine the benefits of physical activity with cold exposure.

Conclusion

Yes, cold increases your overall metabolism, but it's a temporary effect that boosts your total daily energy expenditure rather than fundamentally changing your basal metabolic rate. This metabolic spike is a result of thermogenesis, including shivering and the activation of heat-generating brown fat. Over time, regular cold exposure can lead to metabolic adaptations like increased brown fat and improved insulin sensitivity, contributing to better metabolic health and supporting weight management. For those looking to use cold strategically, consistency and a gradual approach are essential to reap the benefits safely.

Frequently Asked Questions

No, while cold exposure increases calorie burn, it's not a significant amount for dramatic weight loss on its own. It is a supplementary tool to a proper diet and consistent exercise routine.

Non-shivering thermogenesis (NST) is a more sustained and efficient way to burn calories over time, as it uses brown fat to generate heat. Shivering is a short-term, energy-intensive response to acute cold.

The immediate metabolic boost during cold exposure is temporary. However, regular, chronic cold exposure can lead to metabolic adaptations, such as increased brown fat activity, that can have more lasting effects on your resting energy expenditure.

BAT is a type of fat that, unlike white fat, is highly active and burns energy (especially fat) to generate heat. When activated by cold, it helps to regulate your body's temperature, increasing calorie expenditure.

Ice baths can be safe but require caution. It is essential to start gradually, listen to your body, and ensure you can safely tolerate the temperature. Avoid hyperventilating and consult a professional, especially if you have underlying heart or health conditions.

Shivering can temporarily burn a large number of calories, but intense, voluntary exercise typically offers a more significant and sustainable increase in energy expenditure, contributing more to overall fitness and weight management.

Living in a cold climate will cause your body to adapt and increase its thermogenic activity, but it's an adaptation of total energy expenditure, not a permanent change to your core BMR. Long-term cold acclimation can lead to metabolic adjustments, but the body will still strive for a stable metabolic set point.