Nitrate is an organic or inorganic compound that is a derivative of the elements of nitrogen and oxygen. Inorganic nitrates are formed by bacteria and are typically used as the main ingredient in fertilizers in agriculture (Collins Dictionary; Businessdictionary.com). On the other hand, organic nitrates are manufactured compounds that are generally used in explosives (Businessdictionary.com). When consumed, nitrates, along with water are converted into nitric oxide in the human body.
Nitrates and Nitrites, which is often used synonymously, is the main substance that give processed or cured meats such as sausages, bologna, bacon etc its pink or reddish hue. It is also used to protect cured meats against lipid oxidation (Govari et. al, 2018).
Nitrates, while is used industrially and in some processed foods, is also naturally found in some vegetables such as spinach, arugula, celery, rocket, lettuce, carrots and beetroot (EFSA, 2008). In this case, the nitrates is taken up by the plants as a nutrient and then assimilated into cell protein (Panos, 2008). However, this type of nitrate is considered ‘dietary nitrate’ and healthy to humans in recommended amounts, unlike its chemically laden counterparts which are used in industrialized products and processed foods among other things (Ward et al, 2005).
Nonetheless, research contents that foods which naturally contain nitrates should not be fed to children under three (3) months old as these foods can be contaminated with higher levels of nitrates due to the use of fertilizers or manure(Preboth, 2005).
In general, nitrates or rather, its converted counterparts are considered toxic and can cause severe burns if it should come into contact with the skin as well as the development of certain cancers and other diseases when consumed in high amounts (Ward et. al, 2005; Encyclopedia Britannica).
Nitrates and Nitrites which function as preservative in processed or cured foods have been a controversial subject matter over the years. This is especially due to the potential formation of nitrosamines, which is the substance that is formed when nitrates are used in high concentration in foods that are then cooked at high temperatures. This usually occurs in the case with processed or red meat which usual requires high heat for cooking penetration (Kuhnle and Bingham, 2007). Nitrosamines are generally considered a carcinogen (Agency for Toxic Substances and Disease Registry, 1989) that is, their consumption can cause the body to become toxic and thus lead to the formation of certain diseases, particularly cancers.
One of the principal uses of nitrates dates back to more than Fifty (50) years ago and was generally used as fertilizers in agriculture. However, it’s used in agriculture accelerated in the 1950s to what it is today (Ward, 2009). This was particularly due to its ability to be soluble in water. Nitrates fertilizers include ammonium, sodium, potassium and calcium salts. However, over the years, its usage as span that of being used on crops to be chemically produced and used in food products as well as in drinking water.
While nitrates consumed in high amounts can cause severe health effects in humans, recent research has indicated its beneficial effects to health when it is consumed in reasonable low amounts. Some of the benefits include the lowering of blood pressure as well as cardiovascular health (Lundberg et al, 2006; 2011).
While the controversy continues, here are four (4) reasons to seriously re-consider consuming foods, particularly processed, with these ingredients. These include the development of Methemoglobinemia or ‘blue-baby syndrome, cancer, particularly gastric cancer, thyroid function issues and birth defects. The article will also discuss the differences between nitrates and nitrites, substances that most often used interchangeable as well as misunderstood.
What are Processed Meats/Foods?
Processed meats or foods in general, are those which have been modified in an effort to extend their shelf life and enhance their taste. As such, this alteration of the food changes the way in which it looks and taste. Some of the main methods of processing foods including smoking, curing (using nitrates and nitrites) as well as adding salt or some other form of preservatives. Processed meats include sausages, salami, ham, corn beef and bacon among others. Some meat sauces also falls into this category, as such, you will have to ensure that you read the ingredients list of your food purchases.
Like so many other food ingredients, nitrates and nitrites have had its share of controversies over the years. One minute it is safe and another it is deadly. However, more and more research has been surfacing that has proven the latter. As such, this article will attempt to decipher some of these findings in an attempt to assist you on your quest of health and wellness.
Nitrates vs. Nitrites
Nitrates and Nitrites are often used interchangeable; however, there is a difference. Both nitrates and nitrites naturally occur in the environment as part of the nitrogen cycle and are critical to all living systems, especially plants. However, for nitrogen to be utilized it must be converted to an active form and this is where nitrates comes in. As such, when nitrates are created in the atmosphere through rainstorms etc, it is transported to the soil and hence to crops. The microorganisms in the soil then form nitrates via the breaking down of animal matter.
When humans eat these foods, the nitrates are converted to nitrites via the salivary gland; it is further converted to nitric oxide as it interacts with gastric gas in the stomach. As per meat products, nitrates are naturally converted to nitrites either via that which is naturally occurring in the meat or by adding bacteria that contains nitrates reductase activity (Sebranek and Bacus, 2007; Hammes, 2012). Nitrates in the diet become an issue when it is converted to nitrites or N-nitroso Compounds.
Further, nitrates are usually converted into nitrous acid, nitric acid and nitrates in meat products (Honikel, 2004). This can then act as oxidizing, nitrosating agents or toxic substances. (Honikel, 2004). However, research denotes that the carcinogenic effects can be inhibited if vitamin C and vitamin E (alpha-tocopherol) is used in the curing process (Parthasarathy & Bryan, 2012). Nonetheless, nitrates and nitrites are chemicals that are used mainly as food additives and contribute flavour to the cured meat, inhibit the growth of microorganisms, particularly Clostridium botulinum, and effectively control rancidity by inhibiting lipid oxidation (Pearson and Gillett, 1996).
Four (4) Reasons to avoid the consumption of foods with Nitrates and Nitrites.
1.Methemoglobinemia or ‘blue-baby syndrome
While nitrates are usually found in processed foods, it is also found in drinking water that has been contaminated with high levels of the substance. This in effect can cause a condition known as methemoglobinemia or blue baby syndrome.
Methemoglobinemia is a condition that occurs in infants under six (6) months of age as a result of the body’s inability to deliver the required levels of oxygen to the body (Ward et. al, 2005). This usually happens when infants are exposed to high levels of nitrates usually via elevated levels in drinking water (Ward et. al, 2005). This condition has been documented for more than Fifty (50) years worldwide ever since the first diagnosis in 1945 (Environmental Working Group -EWG).
In fact, the first mentioned of methemoglobinemia has been associated with high level of nitrates in drinking water was reported in 1945 by Hunter Comly who was a pediatric resident in Iowa City. The report concurred that infants who ingest water that was contaminated with high levels of nitrates were likely to develop this condition, particularly those who were experiencing gastrointestinal disturbance (Comly 1945; Fan et al. 1987).
Research has shown that any concentration of nitrates above Fifty (50%) percent in drinking water can result in deaths. As such, the Environmental Protection Agency in the United States has set the maximum contaminant level at 10 mg/L or 10 ppm (parts per million), especially when it comes to the contaminant levels in drinking water. Above this level, nitrates can cause severe toxicity to humans (Toxicology Committee, 1995).
Nonetheless, research has found that even levels below 10 ppm can be harmful to humans which can result in the development of methemoglobinemia (Sattelmacher, 1964; Simon, 1962). However, one must also take care to ensure that they do not consume untreated water in wells, which can be contaminated with nitrates due to the effects of manure, fertilizers or even septic tanks (Preboth, 2005).
While some studies have shown that nitrates above certain levels can affect infants, emerging research has raised significant scientific doubt as to whether there exists a causal link to blue baby syndrome (Avery, 1999; Addiscott and Benjamin, 2006). In fact, these researchers suggest that the condition ‘blue baby syndrome’ could possibly be a cause of several other factors such as gastric upset, protein intolerance as well as heavy metal toxicity. However, they did denote that, while these factors could be among the prominent factors, they did agree that nitrate may have played a minor role in the development of this condition.
Notwithstanding, the European Food Safety Authority states that consumer exposure to nitrates and nitrites was well within the safety limited for all population groups. However, the Authority did admit that children may be exposed to higher concentrations if their diet mostly comprises foods with nitrates.
2. Cancers, particularly Gastric and colorectal cancer
Cancer is a disease that can arise due to many factors, including environmental and lifestyle. However, increasing number of research is finding a causal link between nitrates and the increase risk of cancers particularly gastric and colon (Aarhus University, 2018). According to a study by the Aarhus University in 2018, colorectal cancer is the third leading cause of cancer worldwide and the 1st in Denmark, which was particularly found to have high amounts of nitrates their drinking water. According to the research, the risk of cancer arises when nitrate is converted to N-nitroso, a carcinogenic compound.
In the United States, the established maximum contaminant levels of nitrate in water are 10 ppm (EPA, 1991). However, while nitrates in vegetables may sometimes be in greater concentration than that of water, research indicates that it is still considered good for human health and beneficial and not harmful as in the case of water contamination (US EPA, 1991). This was concurred by Ward et. al, 2005 who stated that the intake of dietary nitrate is less likely to cause an increase in nitrosation compounds due to the presence of nitrosation inhibiters in vegetables such as vitamin C and other antioxidant. The ascorbic acid (Vitamin C) reacts with oxygen, by forming dehydroascorbate, and thus reducing the amount of nitrites which could be oxidized to nitrates (Honikel, 2008).
Nonetheless, L’hirondel et. al, (2006) argues that if the nitrate in drinking water is stated to be toxic if greater than 10 ppm, then the nitrates found in certain foods, particularly leafy vegetables which are comparatively higher, would likely be toxic regardless of the presence of ‘so-called’ nitrosation inhibitors.
This argument seems to have been concurred (while not clear) by Dang, Vu et al, (1994) who expounded that the research of ward et al, (2005), has forgotten that the metabolizing of nitrates in human starts in the mouth via the salivary gland. As such, nitrate would be reduced to nitrites in the mouth and then to nitric oxide and nitrosating compounds, which can react with N-nitroso agents and thus lead to the development of specific cancers, reproductive issues as well as diabetes.
Therefore, while Ward et. al, (2005) touted that nitrate in foods is healthier and beneficial to humans, L’hirondel et al, (2006) believes that the substance is toxic even if ingested via food or drinking water. According to Lundberg et. al, (1994), about 25% of nitrates is secreted in the saliva. However, according to Bartholomew and Hill, (1984), majority of the nitrates that the body absorbs is excreted in the urine while a considerate amount is reabsorbed from the kidney as well as the salivary gland.
Notwithstanding proponent’s studies, Ward et, al. (2005) still theorized that Vitamin C and other dietary antioxidant inhibit nitrates ill-effects in humans, a point of view that was also shared by several studies such as (Bartsch et al 1998; Mirvish et. al 1998; Vermeer et. al. 1999). Further, all of these studies contend that one’s risk of cancers increased with the consumption of drinking water contaminated with nitrates of 10 ppm or higher, especially those whose diet consist mostly of red meat and low levels of vitamin C (De Roos et. al, 2005). Nonetheless, research still denotes that the long-term effects of nitrates and nitrites in the diet can lead to the formation of carcinogens in the human body (Andree et al, 2010; Honikel, 2008).
3. Thyroid function issues
Studies have denoted that the ingestion of nitrate can inhibit the uptake of iodine and thus affects the normal functioning of the thyroid gland (De Groef et al, 2006). Iodine is an essential nutrient that helps to maintain brain and thyroid health. The findings of De Groef et. al, (2006) was concurred by several studies including one conducted in Netherlands on a group of women. In this study, there was an increase prevalence of thyroid hypertrophy among women who consume water with high levels of nitrates (Van Maanen et at, 1996).
Conversely, those who consume water with nitrates levels of less than 50 mg/L were not affected by this condition. Surprisingly though, the research shows that women whose diets were prevalent of dietary nitrates had an increased prevalence of hypothyroidism but not hyperthyroidism.
4. Birth defects
While high levels of nitrates is said to lead to certain types of cancers, research has shown that pregnant women who consume water that is contaminated with nitrates can experience varying birth defects ranging from fetal deaths to spontaneous abortion and even growth retardation (Ward et al, 2018). However, while several studies have found a positive relation between drinking water with high levels of nitrate and birth defects (Center for Disease Control and Prevention, 1996), other researchers have found no positive association (Aschengrau, 1989).
Even though these studies have been conducted Twenty (20) years ago and may be discounted by many, most recent research (Fan and Steinberg 1996; Manassaram et al. 200) still suggests that high doses of nitrates do have a toxic effect on reproduction. In addition, nitrites have also been found to be mutagenic and as such, possess and even more increased possibility of its ill-effects in the human body (Luca et al. 1987).
Here is a summary of the Four (4) reasons to avoid the consumption of foods with Nitrates and Nitrites.
Let’s Sum It Up!
Nitrates and Nitrites are compounds that are commonly used as additives in processed foods particularly sausages, bologna, bacon and red meat in general. When used, nitrates and nitrites affect the quality of the food, help to kill bacteria as well as extend its shelf life. The controversy of nitrates and nitrites arises when they are converted to N-nitroso compounds which are known to be carcinogenic.
Some of the potential health effects of consuming to nitrates, particular in excess of 10ppm, which is the allowable amount, include methemoglobinemia or what is called ‘Blue baby syndrome’, cancers, particularly gastric and colorectal, thyroid dysfunction as well as birth defects.
While recent researches have contend that nitrates in high amounts are toxic to humans health, some research have indicated that in small amounts, nitrates can actually be beneficial to one’s health such as the lowering of one’s blood pressure and improving cardiovascular health.
Nonetheless, for the purposes of meat products, many countries have set limits for nitrates and nitrites. The prevalent established limits are set to 10 ppm or less. Higher concentration is usually stated to cause toxicity and potential health effects.
The debates will certainly continue as the years go by, especially as people become more health conscious about what they put in their body or even on their skin. However, it is always best to continue to do your research and do not take any chances with your health. As without it, you are either living in pain or spending all you have to feel well or worst yet, dead.
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