Newspaper headlines suggest that eating “a ham sandwich a day” could increase the risk of type 2 diabetes, but experts caution that the issue is more complex than these headlines imply. A study involving nearly two million people across 20 countries has identified a link between both red and processed meats—such as steak, bacon, and sausages—and an increased risk of diabetes.
While the study is well-conducted, it does not establish a direct cause-and-effect relationship between meat consumption and diabetes. It is challenging to account for all potential risk factors, including other dietary habits and lifestyle choices. Dr. Duane Mellor of the British Dietetic Association noted that while the study controlled for factors like body weight, smoking, alcohol consumption, and low vegetable intake, some data, such as family history and waist circumference, were missing. Despite this, the researchers remain confident in their findings.
The study, published in The Lancet Diabetes and Endocrinology journal, highlights the need to balance meat consumption as part of a healthy diet, rather than eliminating it entirely. Prof. Naveed Sattar from the University of Glasgow emphasized that although the evidence is observational, the study supports existing recommendations to reduce red and processed meat intake to potentially lower the risk of both type 2 diabetes and cardiovascular diseases.
The research found that consuming two thick slices of ham daily (50g) or a small steak (100g) may be associated with increased risk, but the effects of chicken and other white meats were less clear. The NHS advises limiting red and processed meat intake to 70g per day due to links with bowel cancer, placing processed meats in a risk category similar to tobacco smoking and asbestos.
Processed meats often contain chemicals from preservation methods like smoking, curing, or adding salt, which may contribute to health risks. Although meat provides important nutrients, such as protein, vitamins, and minerals, it can also be high in saturated fat, which is associated with elevated cholesterol levels and heart disease.
Prof. Nita Forouhi from the University of Cambridge, the lead researcher, underscored the value of the study in highlighting the association between processed and red meats and an increased risk of type 2 diabetes. She supports recommendations to limit the consumption of these meats to reduce diabetes incidence.
Type 2 diabetes is characterized by high blood sugar levels due to insufficient insulin production or ineffective insulin use. Risk factors include obesity, high blood pressure, ethnicity, and family history. Dr. Mellor advised those reducing meat intake to ensure they still receive essential nutrients like iron and vitamin B12 from other sources. Good sources of vitamin B12 include milk, cheese, eggs, fortified yeast extracts (like Marmite), fortified breakfast cereals, and fortified soy products.
