Harvard researchers say people who consume high amounts of red meat and other animal products may be at risk for type 2 diabetes, largely due to the heme iron present in these foods.

The study, conducted by researchers at the Harvard T.H. Chan School of Public Health, found that higher intakes of heme iron, which is primarily found in red meat and other animal products, is associated with a greater risk of developing type 2 diabetes, providing a detailed understanding of this connection.

Heme iron, found in red meat, poultry, and fish, is a type of iron derived from hemoglobin and myoglobin. It is highly bioavailable, meaning the body absorbs it easily.

Although it is essential for oxygen transport and energy production, excessive consumption, especially from red meat, increases health risks, including type 2 diabetes.

The study, published in Nature Metabolism, used 36 years of dietary data from 206,615 adults who took part in the Nurses’ Health Studies I and II and the Health Professionals Follow-up Study.

The researchers examined participants’ intake of different types of iron — total, heme, non-heme, dietary and supplemental — and analyzed their risk of developing type 2 diabetes, after taking into account other health and lifestyle factors.

The study showed that participants who had the highest heme iron intake had a 26% higher risk of developing type 2 diabetes than those with the lowest intake.

Heme iron was found to account for more than half of the risk of type 2 diabetes associated with unprocessed red meat, and also for a moderate portion of the risk associated with certain dietary patterns associated with diabetes.

Research has also identified an association between high intakes of heme iron and elevated levels of blood metabolic biomarkers associated with type 2 diabetes, such as C-peptide, triglycerides, and markers of iron overload.

The implications of these findings for public health provide insight into how dietary guidelines should be formulated.

It also raises concerns about the inclusion of heme iron in plant-based meat alternatives, which are becoming increasingly popular.

According to the researchers, further investigation is needed into the potential health effects of these products.

“Reducing heme iron intake, particularly from red meat, and adopting a more plant-based diet may be effective strategies for reducing diabetes risk,” said Frank Hu, the Frederick J. Stare Professor of Nutrition and Epidemiology and corresponding author of the study.

However, the study had some limitations.

There may be some errors in the data, and not all factors that could influence the results have been fully taken into account.

They also said findings from a predominantly white study population should be validated in other racial and ethnic groups.