Dietary nitrate and nitrite were not associated with pancreatic cancer, 7 and dietary nitrate, including those found in processed meats, did not increase the risk of overall breast cancer. Though IARC states that dietary nitrates or nitrites found primarily in meat sources are probably carcinogenic to humans, conclusions from epidemiologic studies are somewhat mixed. High nitrate intake may be associated with a decreased risk of gastric cancer, whereas nitrite intake may increase the risk of glioma and thyroid and gastric cancers.
At this time, no studies have shown a consistent association between high intakes of nitrate or nitrite and other types of cancers. Show More. Login Register. We want you to take advantage of everything Cancer Therapy Advisor has to offer.
Nitrosamines can also be created directly in foods through high-heat cooking, as with fried bacon. When cooked at high temperatures this allows them to more easily form nitrosamines, the cancer-causing compound. In processed meats, it's the nitrites' proximity to proteins, plus being cooked at high temperatures, that create cancer-causing nitrosamines Credit: Getty. But Allen adds that nitrites are just one reason processed meats contribute to bowel cancer, and their relative importance is uncertain.
Other factors that may contribute include iron; PAHs polycyclic aromatic hydrocarbons which are formed in smoked meats; and HCAs heterocyclic amines , which are created when meat is cooked over an open flame — and which also are tumour-promoting. While the International Agency for Research on Cancer categorises processed meat a carcinogen, the risk is quite small.
In the UK, for example, six out of people will get bowel cancer in their lives. Of those who eat 50 grams processed meat about three rashers of bacon daily, the chance is seven out of In , three US scientists received the Nobel prize for their discoveries around the role of nitric oxide — a gas — in the cardiovascular system.
Limited capacity to produce nitric oxide is associated with heart disease, diabetes and erectile dysfunction. Found in vegetables like beets, nitrites also help us form nitric oxide, which lowers blood pressure Credit: Getty. One way the body makes nitric oxide is from an amino acid a building block of protein called arginine. We also know that this may be particularly important in older people, since natural nitric oxide production via arginine tends to drop with ageing.
Nitrates in leafy greens are less likely to form cancer-causing nitrosamines and have plenty of health benefits Credit: Getty. So when most of the nitrates in our diets come from vegetables — and in turn encourage nitric oxide formation — they are probably good for us. But the report also noted that people of all age groups can exceed this ADI quite easily. Because many other factors besides nitrate are involved in the endogenous formation of N-nitrosation compounds, it is possible that exposure to nitrate is not a rate-limiting factor in most circumstances.
This makes the setting of regulatory standards for nitrate exposure from the environment a complex issue. Abstract This article focuses on the relationship between exposure to nitrates in the environment and subsequent risk of human cancer.
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