Cold temperatures in the home are linked to worse health outcomes, confirms a new report by Public Health Wales.

The research found exposure to temperatures of 18°C or below were associated with negative effects on health including those related to heart and lung health, sleep, physical performance and general health.

Older people and those with long-term health problems were more vulnerable to negative impacts from cold temperatures. For example, indoor temperatures at or below 18.2°C were associated with increased severity of symptoms in patients with chronic respiratory problems. However, no association was observed between indoor temperature and viral infections for healthy adults and children in winter.

Hayley Janssen, public health researcher at Public Health Wales, said: “The overall evidence suggests that households will avoid many of the health risks associated with cold homes if they generally maintain home temperatures of 18°C or above, which is the minimum temperature to which the WHO and UK authorities, including Wales currently recommend the general population heat their homes. As temperatures dip below 18°C some health risks gradually increase but these can vary with vulnerability and age.

“Our research did also show that there are significant gaps in the evidence – such as the effects of colder temperatures on children and young people, the long-term health and well-being effects of exposure to low indoor temperatures and the impact of cold indoor temperatures on mental health and well-being.”

Setting temperature recommendations is one way of helping the public to make healthy informed choices about how much to heat their home. Welsh Government currently advise households to set temperatures to 21°C in the living room and 18°C in other rooms for 9 hours in every 24-hour period on weekdays, and 16 hours in a 24-hour period on weekends.

For those households with vulnerable people, the recommendations are 23°C in the living room and 18°C in other rooms achieved for 16 hours in a 24-hour period.

The report recognises that many households are unable to reach such targets due to financial constraints. This may particularly be the case given increasing fuel poverty, costs of living and energy prices. Therefore, further efforts to understand the relationship between fuel poverty and exposure to cold indoor temperatures and health and well-being is warranted.

The report acknowledges that temperature recommendations also need to be considered in the context of other factors, including the contribution of household emissions to climate change and household occupants. For example, the Lullaby Trust recommend a room temperature of 16-20°C, to reduce the risk of infants overheating, which is a risk factor for sudden infant death syndrome (SIDS).

‘A systematic literature review on cold homes and their association with health and well-being’, was produced by Policy and International Health, WHO Collaborating Centre on Investment for Health and Well-being, Public Health Wales and the Public Health Collaborating Unit, Bangor University. It was co-funded by the Welsh Government and Public Health Wales.