Study Links Body Temperature Variations to Women's Autoimmune Risk

Women’s higher risk of developing autoimmune conditions may be partly linked to differences in body temperature and their effects on immune responses, according to research led by scientists at the Institute Pasteur in Paris. The findings suggest that natural temperature variations may influence how immune cells respond to infections and other stimuli, offering a possible explanation for some differences in immune function between women and men.

The research, led by Elizabeth Maloney and colleagues, examined how body temperature relates to immune activity. The team analyzed data from healthy adults in the Milieu Intérieur cohort and conducted laboratory experiments to investigate how temperature changes affect immune responses. Their findings indicate that body temperature may influence immune activity differently according to sex and the type of stimulus involved.

Key Highlights:

• Body temperature fluctuations may contribute to women’s higher risk of autoimmune diseases
• Research suggests temperature changes can influence immune cell activity and signaling
• Further studies are needed to confirm the link between temperature and autoimmune conditions

Body temperature naturally varies throughout the day and can also change with age, hormonal fluctuations and the menstrual cycle. Women experience temperature changes associated with reproductive hormonal cycles, while menopause brings further changes to their hormonal environment. Researchers are investigating whether these variations may influence the regulation of immune cells and contribute to differences in susceptibility to immune-related diseases.

The study revealed several immune-related genes and proteins that were associated with body temperature. Laboratory experiments also demonstrated that febrile temperatures can diminish some immune signaling reactions such as interferon-gamma signalling when blood samples were exposed to various temperatures. This is a crucial pathway for coordinating the body's defense against infections. These findings indicate that temperature could influence immune responses, rather than just elevating or lowering immunity.

Elizabeth Maloney gave the same results at the October 12th-13th 2026 Immunology of the Exposome conference held at the Royal Society in London. The meeting brought together researchers working on environmental exposure interaction with biological processes to influence chronic inflammatory diseases.

But the researchers have not confirmed that temperature changes are actually responsible for the autoimmune diseases and they have not been able to fully explain why women are more likely to be affected by these diseases. Autoimmune diseases are complex disorders that result from interactions between genes, hormones, the environment and how the immune system regulates itself. The results provide one explanation, which needs to be further explored.

The study has been released as a preprint on the medRxiv server and is not yet peer-reviewed. Additional research with larger, more heterogeneous patient populations is required to determine if differences in temperature affect the immune system and if these differences are a factor in disease development, as well as the potential use of temperature as a tool in the prevention or treatment of these diseases.