Study shows molecular link between diet and cancer risk

An international group of scientists has detected a direct molecular connection between dairy and meat diets and the development of antibodies in the blood that raises the risk of cancer development.

This link may explain why individuals who consume large quantities of red meat and dairy products experience more number of cancers. This is analogous to the relationship between elevated cholesterol and a higher risk of heart disease.

The research work was headed by Dr Vered Padler-Karavani from the Department of Cell Research and Immunology at the Shmunis School of Biomedicine and Cancer Research at Tel Aviv University’s George S. Wise Faculty of Life Sciences. The study results were published in the BMC Medicine journal on September 23^rd, 2020.

The sugar molecule Neu5Gc is found in mammals’ tissues but not in fish or poultry. In humans, antibodies against Neu5Gc are produced in infancy itself, when they are initially exposed to meat and dairy products.

Although it is known that such antibodies raise the risk of cancer, particularly colorectal cancer, no direct association had been identified between the antibodies and the consumption of dairy and meat products.

For the research work, the team utilized samples from NutriNet-Santé, a wide national nutritional survey held in France. Salam Bashir, a PhD student in Dr Padler-Karavani’s laboratory, along with other members of the team, quantified the amount of Neu5Gc sugar in a wide range of meat and dairy food products that are common in the French diet and computed the daily intake of Neu5Gc by 19,621 adults aged 18 and above. All these adults reported their entire food consumption online over a period of several days.

Later, the researchers took a representative sample of 120 participants and examined the concentrations of the anti-Neu5Gc antibodies in their blood.

On the basis of these findings and the quantification of Neu5Gc sugar in different food products from France, Dr Padler-Karavani and her group developed an index, known as the Gcemic index. This index classifies food products whose excessive intake can lead to increased antibodies—and potentially to increased risk of cancer.

We found a significant correlation between high consumption of Neu5Gc from red meat and cheeses and increased development of those antibodies that heighten the risk of cancer.”

Dr Vered Padler-Karavani, Department of Cell Research and Immunology, Shmunis School of Biomedicine and Cancer Research, Tel Aviv University

Dr Padler-Karavani continued, “For years there have been efforts to find such a connection, but no one did. Here, for the first time, we were able to find a molecular link thanks to the accuracy of the methods used to measure the antibodies in the blood and the detailed data from the French diet questionnaires.”

This combination of techniques enabled the team to estimate that those who consume plenty of cheese and red meat will develop high levels and a different range of the antibodies, and hence may have a higher risk for cancer—specifically colorectal cancer, but also other cancers, concluded Dr Padler-Karavani.