Nitrates and nitrites are hot topics these days – and are largely misunderstood. It may come as a surprise to learn that both of these molecules are critically important for the human body. They get converted into nitric oxide, which is essential for normal metabolism as well as the functioning of the cardiovascular system. Nitric oxide signals arteries to relax and expand, and helps immune cells kill bacteria. It is also part of the brain system that allows brain cells to communicate with each other.
About half of the nitric oxide in our body comes from the foods we eat, while the other half is made in the body during normal metabolism. Foods that have the highest levels of nitrate include green leafy vegetables, beets, celery and radishes. Vegetables make up about 85 – 90% of the dietary intake of nitrate. The remaining 10% comes largely from cured meats.
Nitrate and nitrites are used as foods additives in cured meat. Sodium nitrite or naturally-sourced nitrite-rich celery extract are added to cured meat to act as antioxidants and prevent bacterial growth. This can help safeguard Canadians against Clostridium botulinum, which is a harmful,
disease-causing bacteria. Nitrates and nitrites in cured meat also keep the fat from breaking down and causing a negative change in flavour. Both of these additives are approved for use in Canada and around the world.
Cancer and Nitrates?
The World Cancer Research Fund states that nitrites can react with protein-rich foods, such as meat, and produce nitrosamines, which have been linked to cancer. However, some health experts argue that this link is weak, since it is only based on epidemiological studies, which can never prove cause and effect.
Although nitrates are found naturally in vegetables, nutritional experts say they are safe because the presence of vitamins and antioxidants cancels out any negative impacts. Based on what’s been seen in vegetables, antioxidants such as vitamin C are added to all cured meat products. This is a highly effective method that has been substantiated by more than 30 years of experience and public health monitoring. It is done in order to inhibit the formation of nitrosamines, which are potentially harmful.
For more information about the allowable input level of nitrate and nitrite in cured meats, please see the Meat Hygiene Manual of Procedures on the Canadian Food Inspection Agency’s website.