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nitrosamines [2026/09/15 06:25] – [Formation of nitrosamines] gary1nitrosamines [2026/09/15 07:34] (current) gary1
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 =====Why do we have nitrates or nitrites added to processed meats====== =====Why do we have nitrates or nitrites added to processed meats======
-  *nitrites are needed in cured meats to prevent **[[botulism]]**+  *nitrites are needed in cured meats to prevent **[[botulism]]** and currently there has not been found a suitable alternative
   *just adding pure salt to meat does little to prevent botulism, but it will delay the meat going off from other bacteria   *just adding pure salt to meat does little to prevent botulism, but it will delay the meat going off from other bacteria
   ***a bit of history:**   ***a bit of history:**
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 =====Nitrites===== =====Nitrites=====
 +  *total dietary exposure to nitrites is usually set at 0.07 mg nitrites/kg bw/day but most people would exceed this, especially infants eating processed meats(([[https://pmc.ncbi.nlm.nih.gov/articles/PMC12209013/]]))
   *nitrites may be present either via:   *nitrites may be present either via:
     * addition of nitrites to foods such as **cured meats**     * addition of nitrites to foods such as **cured meats**
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     * nitrites naturally occurring in foods     * nitrites naturally occurring in foods
   *a higher nitrite intake in men was linked to higher rates of [[neo_colorectal]]    *a higher nitrite intake in men was linked to higher rates of [[neo_colorectal]] 
 +  * possible increased risk of thyroid cancer in women
  
 =====Dietary nitrates===== =====Dietary nitrates=====
 +  * acceptable daily intake (ADI) of nitrates in the European Union is 3.65 mg/kg of body weight
 +  * nitrates are the main source of nitrogen for terrestrial plants
   * mainly found in:   * mainly found in:
     * "uncured meat" products with "no added nitrates or nitrites"     * "uncured meat" products with "no added nitrates or nitrites"
       * this is actually misleading as they usually add nitrates via adding celery and a starter culture of the right bacteria to convert it to nitrite which is back to the imprecise Medieval method but it is required to be labeled uncured as it does not have synthetic additives but only biologic additives       * this is actually misleading as they usually add nitrates via adding celery and a starter culture of the right bacteria to convert it to nitrite which is back to the imprecise Medieval method but it is required to be labeled uncured as it does not have synthetic additives but only biologic additives
-    * **80% of dietary nitrates come from leafy vegetables, celery and beetroot** and the oral microbiome can convert these to nitrites but this needs further research+    * **80% of dietary nitrates come from leafy vegetables, celery and beetroot** 
 +      * arugula, spinach, and lettuce have the highest nitrate content with beetroot and celery ranking in the next place(([[https://pmc.ncbi.nlm.nih.gov/articles/PMC12209013/]])) 
 +      * concentration largely depending on geographics, seasonality and the cultivation system 
 +      * the highest accumulation of nitrates is observed in the stems, peduncles, and leaves of plants 
 +    * other potential exposures(([[https://pmc.ncbi.nlm.nih.gov/articles/PMC12209013/]])) 
 +      * polluted wells and groundwater from fertilizer run off, treatment of water with chloramines, oxidation of ammonia from human and animal waste, etc 
 +        * maximum permissible concentration of nitrates in drinking water is often set at 50 mg/L 
 +        * this is a major problem in South-West Romania and other countries 
 +        * in 1991, the Nitrates Directive (Journal of Laws UE.L.1991.375.1 of 1991.12.31)) was drawn up to reduce and monitor nitrate pollution of water supplies aimed at protecting human health and aquatic ecosystems.  
 +      * PM atmospheric exposures and contamination of foods etc,  
 +        *  the use of nitrogen oxide-rich manure in agriculture is a major contributor to nitrogen-rich particulate matter emissions 
 +      * anti-sensitivity tooth paste 
 +      * breast milk 
 +      * salivary concentration of nitrates 
 +        * content of nitrates in saliva is about 10 times higher than nitrates in plasma 
 +        * these nitrates are reduced to nitrites by commensal bacteria, and then to biologically active nitric oxides (NO and NO2) and potentially to nitrosamines 
 +          * this may be increased if HCl acid secretion is disturbed 
 +      * endogenous production via production of nitric oxide (NO) 
 +        * L-arginine is metabolized to citrulline with the formation of NO in a pathway that is catalyzed by nitric oxide synthases 
 +    * medications: 
 +      * some antidiarrhoeals, diuretics, vasodilators, nitrosourea
   * **potential effects**   * **potential effects**
     *** production of nitrites** and their issues (see above)     *** production of nitrites** and their issues (see above)
       * uncured meats with bacterial culture conversion of nitrate to nitrite       * uncured meats with bacterial culture conversion of nitrate to nitrite
       * GIT microbiome actions       * GIT microbiome actions
 +        * anaerobic bacteria can convert 20% of nitrates into nitrites (([[https://pmc.ncbi.nlm.nih.gov/articles/PMC12209013/]]))
     * **vasodilational effects** via production of nitric oxide     * **vasodilational effects** via production of nitric oxide
 +      * potential benefits such as blood pressure regulation, improved vascular endothelial function, and enhanced tissue insulin sensitivity
 +      * potentially reduces cardiovascaulr risk in the DASH diet which is 550% of the daily allowable intake of nitrates for an adult 
 +      * possible anti-inflammatory effects
       * potential for hypotension especially in those already on antihypertensive agents       * potential for hypotension especially in those already on antihypertensive agents
     * **nitrates increase risk of aberrant S-nitrosylation**     * **nitrates increase risk of aberrant S-nitrosylation**
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     * **may cause methaemoglobinaemia**     * **may cause methaemoglobinaemia**
       * usually only in infants with very high intakes (eg. contaminated well water or large intakes of nitrate vegetables)       * usually only in infants with very high intakes (eg. contaminated well water or large intakes of nitrate vegetables)
-    * **possible increased risk of thyroid cancer in women**+    * **adverse thyroid effects** 
 +      * nitrates can interfere with gastrointestinal iodine absorption by inhibiting Na+/K + ATP-ase  
 +      * thyroid gland can concentrate monovalent anions, i.e. nitrates, leading to inhibition of iodine uptake 
 +      * nitrates can also interfere with thyroid function by binding to the sodium iodide symporter, thereby interfering with iodide uptake by the thyroid gland 
 +      * maternal exposure to nitrates has been shown to reduce iodine uptake and may result in increased TSH levels in newborns 
 +      * combined exposure to perchlorates, nitrates, and thiocyanates may affect maternal thyroid function and TSH rise during pregnancy and there is a possibility that exposure to these compounds may impair growth in girls aged 6–8 years(([[https://pmc.ncbi.nlm.nih.gov/articles/PMC12209013/]])) 
 +      * a deficiency of selenium in combination with an increased amount of nitrates may have a negative impact on the iron and iodine status of postpartum women 
 +      the effect of nitrates on thyroid function can be strong in the presence of dietary iodine deficiency but when there is adequate dietary iodine, the effect is weak 
 +      genetic factors may be important in this relationship 
 +    * may have benefits in exercise(([[https://pmc.ncbi.nlm.nih.gov/articles/PMC12209013/]])) 
 +      * beet juice (BJ): 
 +        * the International Olympic Committee classified beet juice alongside caffeine, β-alanine, creatine as a dietary supplement that can improve athletic performance when taken in the right dosage and in a specific type of exercise. 
 +        * BJ is a source of dietary fiber, minerals such as calcium, iron, sodium and potassium as well as a number of antioxidant compounds, including betalain. 
 +        * the effects of BJ on physical performance have been attributed to the high levels of inorganic nitrate found in this product (< 250 mg per 100 g of fresh BJ)  
 +        * maximum serum NO2 concentrations are seen 2–3 h after nitrate supplementation 
 +        * nitrate from BJ increases blood flow to type 2 fibers leading to improvements in resistance training, modulates contractile function by modulating Ca2 + handling, increase mitochondrial function reducing oxygen cost during muscle contraction  
nitrosamines.txt · Last modified: 2026/09/15 07:34 by gary1 · Currently locked by: gary1

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