For the researchers, this is a “new piece of evidence” encouraging the “reduction of the use of nitrite additives in meats processed by the food industry”.
A study published this Tuesday evening in PLOS Medicine shows that people with a high degree of exposure to nitrites had “a higher risk of developing type 2 diabetes.” It was carried out by a team of researchers from Inserm, INRAE, Sorbonne Paris Nord University, Paris Cité University and Cnam.
“This is the first large-scale cohort study to suggest an association between nitrite from additives and a potentially increased risk of type 2 diabetes,” explain Bernard Srour, post-doctoral researcher at Inserm, and Mathilde Touvier, Inserm research director, who piloted this study.
These results come from the analysis of data from 104,168 participants from of the NutriNet-Santé cohortfollowed between 2009 and 2021. None of them had type 2 diabetes at inclusion in the study.
These volunteers “reported their food consumption in detail”, which enabled the scientific team to accurately assess their consumption of nitrates and nitrites. Their place of residence was also informed, as well as a wealth of information about them, in order to know their degree of exposure to these substances on a daily basis.
“A higher risk of developing type 2 diabetes”
Both nitrites and nitrates exist naturally in our environment, “in certain foods (especially vegetables) as well as in water and soil; agricultural and industrial practices can accentuate this phenomenon”, explain the researchers.
These two products can also be intentionally added to food, in the form of food additives, writes ANSES. Nitrites are thus “used to prevent the development of pathogenic bacteria, such as salmonella and listeria”, and are especially present in cold cuts.
Thanks to the large cohort available, and the numerous data provided, the researchers were able to establish that “participants with higher exposure to nitrites (specifically from food additives, but also from ‘non-additive’ sources) presented a higher risk of developing type 2 diabetes.”
As a reminder, type 2 diabetes is the most common in France, 92% of diabetics have type 2 diabetes, explains health insurance.
The increased risk of developing this diabetes “was 27% for people with the highest consumption of total nitrites, compared to those with the lowest consumption”, write the researchers. The increased risk climbs to 53% “for people consuming the most nitrites from additives and 26% for nitrites from other sources”, it is specified.
However, no association between exposure to nitrates and the risk of type 2 diabetes was found.
“The need to reduce the use of nitrite additives”
“More than 15,000 packaged products on the French market currently contain nitrites and/or nitrates”, recalls the press release. “Our diet exposes us daily to nitrites and nitrates”, also writes ANSES.
Already in July 2022, ANSES wrote to confirm “the existence of an association between the risk of colorectal cancer and exposure to nitrites and/or nitrates”. The food safety agency also wrote that “other cancer risks are suspected but the available data do not allow, to date, to conclude the existence of a causal link.”
“These results provide a new piece of evidence in the context of current discussions regarding the need for a reduction in the use of nitrite additives in meats processed by the food industry”, write the two researchers at the head of the study.
It could “also support the need for better regulation of soil contamination by fertilizers.”
the French government announced this summer an action plan to reduce, or even eliminate, the use of “nitrogen additives in all food products where this is possible without health impact and as quickly as possible.”
