By K Bharat Kumar

Copyright thehindubusinessline

Recent research has established a link between disturbances in the Earth’s magnetic field driven by solar activity, and the incidence of heart attacks.

The research, drawn from public health data in Brazil, showed women being more susceptible to such geomagnetic influences.

The Brazilian study examined the correlation between hospital admissions and geomagnetic disturbances (GMDs). Researchers from the National Institute for Space Research in Brazil and the University of São Paulo covered data on 1,340 patients, who had been diagnosed with myocardial infarctions between 1998 and 2005. The set included 871 men and 469 women.

Climate change

The researchers used planetary index (Kp) as an indicator of variations in the Earth’s geomagnetic field resulting from solar disturbances. The geomagnetic three-hourly Kp index, introduced in 1949, measures solar particle radiation by its magnetic effects – an important measure for the energy input from solar winds to Earth. Derived from data from 13 observatories around the globe, Kp is a key parameter to investigate long-term climate change in the upper atmosphere, in geospace, and solar winds.

The analysis took into account attributes such as age, gender, and geomagnetic conditions. Days in the study period were classified as ‘quiet’, ‘moderate’, or ‘disturbed’ according to magnetic activity. The data was conducted for three age-groups: 30 and younger, 31–60, and over 60.

Women more susceptible

Results showed that geomagnetic conditions did have an impact on heart attack cases, particularly among women. The rate of relative frequency of these cases during ‘disturbed’ geomagnetic conditions was almost three times greater compared with the ‘quiet’ group.

This is not the first instance where solar activity has interested scientists in trying to establish a correlation with changes in human health status.

A long-term study published in Scientific Reports in 2018 examined relationships between solar and magnetic factors and the time course and lags of autonomic nervous system (ANS) responses to changes in solar and geomagnetic activity.

The study concluded that the nervous system responds to changes in geomagnetic and solar activity, and that these responses are initiated at different times after changes in various environmental factors, and persist over different lengths of time. Also, different individuals respond differently to changes in the same environmental variable, it said.

Another research paper, published in Plos One in 2022, found that the effects of solar activity on endothelial function and inflammatory markers were delayed. (The endothelium is the layer of cells that lines the inner surface of blood vessels, lymphatic vessels, and the heart). Body reacts well after the pollutants have likely disappeared, it noted.

Published on October 6, 2025