"Nitrates" can make you think of school chemistry lessons or fertilizers. Perhaps you are more likely to be very fond of dinner.
If you are thinking of nitrates in the context of food, it is likely to be a negative imaginable image – in particular, perhaps, recent calls for nitrate and nitrite preservatives banned from bacon and ham due to potential effects of cancer causing.
But the relationship between diet nitrates / nitrites and health is more nuanced than just saying "bad for us". For example, high nitrate content of beetroot juice has been credited with lowering blood pressure and enhancing exercise. Nitrates are the active ingredient in some drugs for angina, a condition where reducing blood flow causes chest pain
So are nitrates and nitrites really bad for us?
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Nitrates and nitrites, such as potassium nitrate and sodium nitrite, are naturally occurring chemicals that contain nitrogen and oxygen compounds. In nitrates nitrogen is bonded to three oxygen atoms, whereas nitrite nitrogen has two atomic oxygen. Both legal preserve to combat harmful bacteria in bacon, ham, salami and some cheese. (Read more about how cured meat protects us from food poisoning).
Only around 5% of nitrates on average diet in Europe come from processed meat, while more than 80% from vegetables
around processed meat, you can imagine it is the main source of nitrates in our diet. But in fact only around 5% of the nitrates on average food in Europe come from this source, whereas more than 80% are from vegetables. Vegetables get nitrates and nitrites from the soil that grows on them ̵1; nitrates are part of natural mineral deposits, whereas nitrites are formed by soil microorganisms that fall into animal matter.
Spinach and rocket leaf greens are likely to be top of the crop The content of nitrate, along with other rich sources is the celery and beetroot juice, and carrots. Organic grown vegetables can have lower levels than non-organic vegetables because synthetic synthetic nitrate is not used.
However, there is an important difference between the methods of nitrates and nitrite wrapped in meat compared with vegetables –
Nitrates are somewhat inert to themselves , which is likely not to involve chemical reactions in the body. But the nitrites, and the chemicals generated from them, are much more reactive.
Most nitrites we encounter are not immediately melted, but are changed from nitrates by the action of the bacteria found in our mouth. This means that research shows that the use of an anti-bacterial mouth wash can significantly reduce oral nitrite production.
When nitrites made in our mouth are swallowed, one of the possible things is their reaction to the strong acidic stomach environment to develop nitrosamines – some of them are carcinogenic and linked bowel cancer.
But for this to happen, a source of amines, ammonia-related chemicals that are found abundantly in food protein, are required. Nitrosamines can also be made directly into foods through high heat cooking, such as fried bacon.
It's not so many carcinogenic nitrates / nitrites, but their method is cooked and their local environments – Kate Allen
"It's not so much nitrates / nitrites per se [that are carcinogenic] but the recipe and their local environment are a key factor, "says Kate Allen, executive director of science and public affairs at the World Cancer Research Fund. "For example, nitrites in processed meat are close to proteins (particularly amino acids), when cooked at high temperatures allow them to produce nitrosamines, the cancer-causing compound."  But Allen added that nitrites are just a process of meat that helps with bowel cancer, and their importance is uncertain. Other factors that may contribute are iron; PAHs (polycyclic aromatic hydrocarbons) formed in cereals; and HCAs (heterocyclic amines), which are created when the meat is cooked over an open fire – and also where tumor-promotes.
It is also important to keep the dangers of processed meat in the context. Whereas the International Agency for Research on Cancer compares the processed meat that "is likely to arouse cancer", the risk is relatively small.
For example, in the UK, six in 100 people get bowel cancer in their lives. For those who eat 50 grams of meat (about three bacon rashers) every day, chances are seven out of 100.
Nitrous is not all bad. There is extra evidence that they can provide cardiovascular and other benefits thanks to a molecule called nitric oxide.
In 1998, three US scientists received the Nobel prize for their discoveries around the role of nitric oxide – a gas – in the cardiovascular system. We now know that it is releasing blood vessels, reducing blood pressure and part of the body's armory against infections. The limited capacity to produce nitric oxide is related to heart disease, diabetes and erectile removal.
One form of body that produces nitric oxide comes from an amino acid (a building block of protein) called arginine. But now it is known that dietary nitrates can also contribute significantly to nitric oxide formation. We also know that this is particularly important to older people, because natural production of nitric oxide by arginine often falls into aging.
While nitrates found in ham are chemically identical to those in salads, you should shoot for
Still, while the nitrates found in ham are chemically identical to those in the salad you can eat it, it are the plant based ones you should shoot for.
"We observed increased risk associated with nitrate and nitrite from meat for some cancers, but we have not seen the dangers associated with nitrates or nitrites from vegetables – at least major observations studying estimates estimated from self-reported questionnaires, "says Amanda Cross, a cancer epidemiologist at Imperial College, London.
The Cross adds a "reasonable assumption" that nitrates in leafy greens are more likely to be harmful (ie to form nitrosamines). This is because they are not proteins rich in protein and also contain protective ingredients such as vitamin C, polyphenols and fiber, which are all shown to reduce the development of nitrosamine.
When most nitrates in our diet come from vegetables – thereby encouraging the formation of nitric oxide – probably good for us
So when most of the nitrates in our diet are derived from vegetables – and also encourages the formation of nitric oxide – probably good for us.
A nitric oxide expert has advanced, many of us lack nitrates / nitrites and should be classified as essential nutrients that will help prevent conditions such as heart attacks and strokes.
Right value  It is almost impossible to reliably estimate the use of nitrate food because the food content is hugely variable. "The levels can vary up to 10,000 times for lettuce, and nitrates in drinking water can also vary significantly with legal limitations (50mg / liter)," says nutritional epidemiologist who is Gunter Kuhlne of Reading University of the UK.
"This means that studies that examine the effects of nitrate on health need to be explained carefully, since & # 39; nitrate & # 39; can be just a marker of vegetable consumption" .
A European Food Safety Authority (EFSA) report is an Acceptable Daily Drink or ADI (the amount that can be consumed in a life without fear of health hazards) equivalent to 235mg of nitrate for a person weighing 10 stones (63.5kg / 140lb). However, the report reports that people of all age groups can easily pass this ADI easily.
Nitrite intakes are generally lower (an estimate of average UK consumption of 1.5mg per day), and the EFSA said exposure to nitrite preservatives is within safe levels for all groups population in Europe, except for partial excess of children with diet high in additives.
Some experts argue that nitrate / nitrite ADIs are outdated, and the higher levels are not only safe but useful – as long as they come from vegetables, not processed meat.
Having 300-400mg of nitrates on a go – potentially given by a large rocket and spinach salad, or a beetroot juice shot – is the amount linked to
As usual, the dose is It produces poison, and the levels of 2-9 grams (2000-9000mg) of nitrate can be acutely toxic, causing changes in the hemoglobin present as a blue color to the skin. But it is a difficult level to reach in a sitting, and very unlikely to occur from the food itself – it is more of a risk than, say, exposure to feritliser-contaminated water.
The upshot? If you want to eat the right kind of nitrates and nitrites and avoid potentially carcinogenic, then eat a wide variety of foods with at least five servings a day of fruit and vegetables, and avoid the nibbling on processed meat too often. In this way, the benefits of nitrates and nitrates are almost certainly beyond the downsides.
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