Shafqat Ahmad searches for answers in food and the environment – what is driving our most common diseases?

There are many misconceptions about how lifestyle, heredity and environment contribute to our most common diseases. Fundamentally, everything is connected, according to Shafqat Ahmad, associate professor of epidemiology at Södertörn University.

“The general recommendation is to live healthily, eat well, sleep properly, not smoke and stay physically active. But, even if people follow this advice, they may still have a significantly higher risk of disease due to their genetic makeup,” says Ahmad.

His research journey began with a personal question: “My father, like many others, had type 2 diabetes and I wanted to understand why,” he says.

Doctoral studies in Lund

During his time as a doctoral student at Lund University, he began studying the interaction of genetics, environment and lifestyle. He wanted his research to contribute to both preventing and explaining the progression of major global diseases.

He also spent time at the University of Pennsylvania researching why people of South Asian descent have a greater risk of developing type 2 diabetes and cardiovascular disease at an early age. This is an issue he continues to study in international collaborations.

What does diet actually explain?

Several of the studies that Shafqat Ahmad has led or participated in have shown that unhealthy diets and lifestyles are key risk factors in cardiovascular disease and early death. This was very clear in one international study, published in JAMA Network Open in 2024 External link, opens in new window., where women who followed a Mediterranean-type diet had a lower risk of premature death.

The Mediterranean diet is characterised by lots of plant-based foods such as nuts, seeds, fruit, vegetables, whole grains and legumes, as well as olive oil. It also includes moderate amounts of fish, eggs, dairy products and alcohol, and lower consumption of red meat and sugars.

“The main point is that it is the overall diet that matters, not a single foodstuff,” says Ahmad.

In Swedish population studies External link, opens in new window., he and his colleagues have analysed over a thousand blood metabolites, small molecules that form when the body processes food. They have shown how substances linked to processed red meat can increase the risk of cardiovascular disease and how a diet that is low in fibre can contribute to early changes in the coronary arteries. These changes are not noticeable at first, but can increase the risk of disease in the long term.

Can lifestyle compensate for high genetic risk?

Ahmad and his colleagues showed in a 2013 study in PLoS Genetics, before the large international biobanks existed, that even people who have a high genetic risk of obesity could reduce their future risk by being increasing their physical activity. Their discovery sent a clear public health message: regardless of our genetic predisposition, our lifestyle choices can influence our risk of metabolic disease.

A puzzle built from genes, environment and behaviour

For Ahmad, it is vital to understand the interaction of genetics and the environment. He describes this as part of a larger biological system.

“People are born with different genetic risks, so we don’t all start from the same place. This means that preventive measures and treatment need to be tailored to each individual, which is at the heart of precision medicine,” he says.

In an article in Nature Reviews Cardiology External link, opens in new window. he underlines how future research must combine different biological data sources with advanced computational models and studies of different population groups. The aims are to identify important genes and biological mechanisms, and to understand how these are affected by lifestyle and environment.

International career and education for the future

After completing his doctorate, Shafqat Ahmad has worked at both Harvard University and Uppsala University. He has received several international awards, including the Rising Star Award at the European Association for the Study of Diabetes’ conference in Barcelona in 2019, and was also named one of Uppsala University’s leading young researchers.

He has worked at Södertörn University since 2024, where he is programme convenor for the Master’s programme in Infectious Disease Control. The programme combines epidemiology, data analysis and environmental health with a global perspective.

“Students discuss how environmental factors, lifestyles and social structures affect both health and the spread of infection. The diversity of the student group allows us to examine health from multiple perspectives,” says Ahmad.