Nitrates and nitrites may as well be the creepy Shining twins of processed foods. Instead of appearing in deserted hallways, this pair shows up in deli and other cured meats. And, just like those creepy twins, these preservatives typically portend something bad.
The preservative pair isn’t inherently bad. The organic nitrogen compounds naturally occur in plants and animals, including in humans, and they play a key role in helping plants and animals grow. But ingesting them, whether as preservatives in meats or in contaminated groundwater, comes with complications.
A paper published last week in the journal PLOS Medicine, the first large-scale cohort study of its kind, finds a link between half this duo and a common chronic illness. Nitrites, it turns out, may increase the risk for type 2 diabetes.
Science in action — The paper analyzed existing data from the French NutriNet-Santé study that covered 11 years of information on over 100,000 adults. Between 2009 and 2021, participants submitted dietary records that showed exposure to nitrites and nitrates. A follow-up with participants revealed 969 cases of type 2 diabetes.
What makes it unique is that it’s the “first large-scale cohort study ... to suggest an association between additive-originated nitrites and a higher type-2 diabetes risk,” authors Bernard Srour and Mathilde Touvier write to Inverse. Both are nutritional epidemiology researchers at Sorbonne Paris Nord University. The term “additives-originated nitrites” refers to nitrites that are added to meat for preservative purposes and aren’t naturally occurring.
The data aligns with prior associations between total dietary nitrites and risk for this condition. It’s been well-known, according to the researchers, that nitrites are involved in forming colorectal cancer, but their role in type-2 diabetes “was hardly ever investigated in epidemiological studies,” the pair writes.
The authors stipulate that they observed no association between nitrates with type 2 diabetes, on the other hand. Srour and Touvier have three hypotheses why. For one, nitrates and nitrites have different effects on health, and only a portion of ingested nitrates are reduced to nitrites, which are then converted to nitric oxide in the stomach; the remaining unconverted nitrates have different effects.
It is also possible that nitrates have a link with type 2 diabetes, but it’s weaker than that of nitrites, which would require a larger sample and strong statistical power for confirmation. Lastly, vegetables contain more nitrates, so the benefits of eating veggies may have counteracted any risks from nitrates.
Why it’s a hack — Type 2 diabetes comes from our cells’ inability to respond to the hormone insulin, which lets them turn blood sugar into energy. This unresponsiveness is called insulin resistance. N-nitroso compounds, which result from ingested nitrites, can play a role in developing insulin resistance by disrupting insulin and what are known as insulin-like growth factor signaling pathways, which allow the hormone to bind to proper receptors on cells.
However, it wasn’t only food-related nitrites that seemed to contribute to this risk.
“The most surprising finding was that the association between nitrites and type-2 diabetes was not limited to those from food additives sources,” Srour and Touvier write to Inverse. This connection means that both food and agricultural industries could stand to improve.
“These results still provide a new piece of evidence in the context of current discussions regarding the need for a reduction of nitrite additives’ use in processed meats by the food industry and could support the need for better regulation of soil contamination by fertilizers,” the authors write to Inverse.
How it affects longevity — Diabetes affects about 10 percent of Americans, according to the Centers for Disease Control (C.D.C.), and the vast majority of those cases are type 2.
A full, healthy life with type 2 diabetes is well within reach for many, but the diagnosis does bring additional risk factors. If not properly controlled, blood sugar can build up in the blood without changing into energy, potentially causing other severe conditions like heart and kidney disease.
Managing type 2 diabetes comes with a slew of new responsibilities in addition to healthy eating and regular exercise. Regular blood sugar checks are in order, and one may be prescribed insulin.
These chemical twins may seem daunting at first, but cutting back on them considerably brightens health outcomes.