Cold at home: an underestimated risk

By Ana Espino | Published on December 17, 2025 | 3 min read


Cold indoor temperatures—often below 18 °C—represent a health risk that remains underestimated, despite official recommendations, notably from the WHO. Such environments are common in situations of energy poverty, particularly in temperate or cold countries, and mainly affect older adults, frail individuals, or those with low incomes.

The problem is exacerbated by rising energy prices, poorly insulated housing, and social inequalities, which limit households’ ability to adequately heat their homes. While several harmful effects of cold exposure have been suggested (cardiovascular, respiratory, musculoskeletal, or sleep-related disorders), the scientific evidence has so far been scattered and outdated, and has not allowed the definition of precise intervention thresholds according to population profiles.  

In this context, the present study was initiated to update knowledge since 2014 on the impact of cold indoor environments on physical health, mental health, and well-being, focusing on studies conducted in climatic contexts comparable to those of European countries.    

What is the impact of cold at home?  

Twenty studies, drawn from seven medical databases, were selected using a rigorous methodology. Inclusion criteria required objective measurements of indoor ambient temperature within homes, in countries with temperate or cold climates. Most studies focused on older adults, a population particularly sensitive to the effects of cold.

Among these 20 studies, 17 identified significant negative health effects associated with low indoor temperatures (<18 °C). From a cardiovascular perspective, several studies reported increased blood pressure, electrocardiographic (ECG) abnormalities, and higher platelet counts. From a respiratory standpoint, worsened symptoms were reported in patients with COPD living in cold environments.  

Sleep was also affected. Cold temperatures delayed sleep onset, reduced sleep quality, and increased nighttime awakenings, notably through a rise in nocturia (frequent nighttime urination). In terms of physical function, cold exposure was associated with reduced muscle strength, particularly in the lower limbs, increasing the risk of falls among older adults.

Finally, overall self-perceived health was impaired, with residents of cold homes more frequently reporting poor perceived health, independently of other factors. Data on mental health, children, and long-term effects remain limited and insufficiently explored.    

An invisible but very real risk  

Chronic exposure to cold indoor environments constitutes an underestimated risk factor that can impair cardiovascular, respiratory, and physical health, as well as overall quality of life. The aim of this review was to synthesize recent evidence and identify areas that remain insufficiently documented. The study confirms that cold housing has a tangible impact on health, particularly among older adults or individuals with chronic conditions.  

However, methodological limitations persist and justify further research. Available studies remain highly heterogeneous, often conducted on small samples, with limited longitudinal data. The role of confounding factors (humidity, ventilation, building quality, energy poverty) is still poorly explored, and critical temperature thresholds vary according to individual profiles.

Future perspectives should include prospective studies integrating social, climatic, and medical data, as well as the evaluation of concrete interventions such as energy-efficient home renovations or heating assistance programs. Specific recommendations could then be developed for the most vulnerable populations, making thermal comfort a recognized determinant of health in its own right.

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