Jump to content

Nitrogen balance: Difference between revisions

From Wikipedia, the free encyclopedia
Browse history interactively
← Previous editNext edit →
Content deleted Content added
VisualWikitext
m Changed a bit of the terminology
m Add a reference
Line 18: Line 18:
Negative nitrogen balance is associated with burns, serious tissue injuries, fever, [[hyperthyroidism]], wasting diseases, and periods of fasting. This means that the amount of nitrogen excreted from the body is greater than the amount of nitrogen ingested.<ref name="urlVII. Monitoring Nutrition Therapy">{{cite web |url=http://healthlinks.washington.edu/nutrition/section7.html |title=VII. Monitoring Nutrition Therapy |archive-url=https://web.archive.org/web/20110928120632/http://healthlinks.washington.edu/nutrition/section7.html |archive-date=2011-09-28 |url-status=dead }}</ref> A negative nitrogen balance can be used as part of a clinical evaluation of malnutrition.<ref name="pmid18403920">{{cite journal |author=Barbosa-Silva MC |title=Subjective and objective nutritional assessment methods: what do they really assess? |journal=Curr Opin Clin Nutr Metab Care |volume=11 |issue=3 |pages=248–54 |date=May 2008 |pmid=18403920 |doi=10.1097/MCO.0b013e3282fba5d7 |s2cid=26831957 }}</ref>
Negative nitrogen balance is associated with burns, serious tissue injuries, fever, [[hyperthyroidism]], wasting diseases, and periods of fasting. This means that the amount of nitrogen excreted from the body is greater than the amount of nitrogen ingested.<ref name="urlVII. Monitoring Nutrition Therapy">{{cite web |url=http://healthlinks.washington.edu/nutrition/section7.html |title=VII. Monitoring Nutrition Therapy |archive-url=https://web.archive.org/web/20110928120632/http://healthlinks.washington.edu/nutrition/section7.html |archive-date=2011-09-28 |url-status=dead }}</ref> A negative nitrogen balance can be used as part of a clinical evaluation of malnutrition.<ref name="pmid18403920">{{cite journal |author=Barbosa-Silva MC |title=Subjective and objective nutritional assessment methods: what do they really assess? |journal=Curr Opin Clin Nutr Metab Care |volume=11 |issue=3 |pages=248–54 |date=May 2008 |pmid=18403920 |doi=10.1097/MCO.0b013e3282fba5d7 |s2cid=26831957 }}</ref>


Nitrogen balance is the traditional method of measuring dietary protein requirements.<ref>Institute of Medicine. ''Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein and Amino Acids (Macronutrients).'' The National Academies Press: 2005</ref> Determining dietary protein requirements using nitrogen balance requires that all nitrogen inputs and losses are carefully collected, to ensure that all nitrogen exchange is accounted for.<ref>Rand WM, Pellett PL, Young VR (2003). ''Meta-analysis of nitrogen balance studies for estimating protein requirements in health adults.'' Am.J.Nutr 77(1):109-127.</ref> To control nitrogen inputs and losses, nitrogen balance studies usually require participants to eat very specific diets (so total nitrogen intake is known) and stay in the study location for the duration of the study (to collect all nitrogen losses). Because of these conditions, it can be difficult to study the dietary protein requirements of various populations using the nitrogen balance technique (e.g. children).<ref>{{cite journal |vauthors=Elango R, Humayun MA, Ball RO, Pencharz PB | year = 2011 | title = Protein requirements of healthy, school-aged children determined by the indicator amino acid oxidation method | journal = Am. J. Clin. Nutr. | volume = 94 | issue = 6| pages = 1545–1552 | doi=10.3945/ajcn.111.012815| pmid = 22049165 | doi-access = free }}</ref>
Nitrogen balance is the traditional method of measuring dietary protein requirements.<ref>Institute of Medicine. ''Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein and Amino Acids (Macronutrients).'' The National Academies Press: 2005</ref> Determining dietary protein requirements using nitrogen balance requires that all nitrogen inputs and losses are carefully collected, to ensure that all nitrogen exchange is accounted for.<ref>Rand WM, Pellett PL, Young VR (2003). ''Meta-analysis of nitrogen balance studies for estimating protein requirements in health adults.'' Am.J.Nutr 77(1):109-127.</ref> To control nitrogen inputs and losses, nitrogen balance studies usually require participants to eat very specific diets (so total nitrogen intake is known) and stay in the study location for the duration of the study (to collect all nitrogen losses). Exercise also affects nitrogen excretion <ref>{{cite journal |last1=Clauss |first1=Matthieu |last2=Burkhardt |first2=Meike |last3=Wöber |first3=Sophie |last4=Skålhegg |first4=Bjørn Steen |last5=Jensen |first5=Jørgen |title=Effect of five hours of mixed exercise on urinary nitrogen excretion in healthy moderate-to-well-trained young adults |journal=Frontiers in Nutrition |date=21 February 2024 |volume=11 |doi=https://doi.org/10.3389/fnut.2024.1345922 |url=https://www.frontiersin.org/articles/10.3389/fnut.2024.1345922/full}}</ref>. Thus nitrogen balance studies usually require controlled conditions to obtain reliable results. Because of these conditions, it can be difficult to study the dietary protein requirements of various populations using the nitrogen balance technique (e.g. children).<ref>{{cite journal |vauthors=Elango R, Humayun MA, Ball RO, Pencharz PB | year = 2011 | title = Protein requirements of healthy, school-aged children determined by the indicator amino acid oxidation method | journal = Am. J. Clin. Nutr. | volume = 94 | issue = 6| pages = 1545–1552 | doi=10.3945/ajcn.111.012815| pmid = 22049165 | doi-access = free }}</ref>


Dietary nitrogen, acquired from metabolizing proteins and other nitrogen-containing compounds, has been linked to changes in genomic evolution. Species that primarily obtain energy from metabolizing nitrogen-rich compounds use more nitrogen in their [[DNA]] than species that primarily break down carbohydrates for their energy{{citation-needed|date=October 2019}}. Dietary nitrogen alters codon bias and genome composition in parasitic microorganisms.<ref name="pmid27842572">{{cite journal |author=Seward EA and Kelly S |title=Dietary nitrogen alters codon bias and genome composition in parasitic microorganisms |journal=Genome Biology |volume=17 |issue=226 |pages=226 |date=Nov 2016 |pmid=27842572 |doi=10.1186/s13059-016-1087-9 |pmc=5109750 |doi-access=free }}</ref>
Dietary nitrogen, acquired from metabolizing proteins and other nitrogen-containing compounds, has been linked to changes in genomic evolution. Species that primarily obtain energy from metabolizing nitrogen-rich compounds use more nitrogen in their [[DNA]] than species that primarily break down carbohydrates for their energy{{citation-needed|date=October 2019}}. Dietary nitrogen alters codon bias and genome composition in parasitic microorganisms.<ref name="pmid27842572">{{cite journal |author=Seward EA and Kelly S |title=Dietary nitrogen alters codon bias and genome composition in parasitic microorganisms |journal=Genome Biology |volume=17 |issue=226 |pages=226 |date=Nov 2016 |pmid=27842572 |doi=10.1186/s13059-016-1087-9 |pmc=5109750 |doi-access=free }}</ref>

Revision as of 11:08, 12 March 2024

In human physiology, nitrogen balance is the net difference between bodily nitrogen intake (ingestion) and loss (excretion):

Nitrogen balance is used as an index of protein metabolism. When more nitrogen is gained than is lost by an individual, they are considered "in positive nitrogen balance" and a state of overall protein anabolism. In contrast, a "negative nitrogen balance", in which more nitrogen is lost than is gained, indicates a state of overall protein catabolism.[1]

The body obtains nitrogen from dietary protein, sources of which include meat, fish, eggs, dairy products, nuts, legumes, cereals, and grains. Nitrogen loss occurs largely through urine in the form of urea, as well as through feces, sweat, and hair and skin growth.

Blood urea nitrogen and urine urea nitrogen tests can be used to estimate nitrogen balance.

Nitrogen Balance and Protein Metabolism

Nitrogen is a fundamental component of amino acids, the molecular building blocks of protein. Therefore, measuring nitrogen intake and nitrogen loss can be used to study protein metabolism.[2]

Positive nitrogen balance is associated with periods of growth, hypothyroidism, tissue repair, and pregnancy. Because of this, the intake of nitrogen into the body is greater than the loss of nitrogen from the body. Thus, there is an increase in the total body pool of protein.

Negative nitrogen balance is associated with burns, serious tissue injuries, fever, hyperthyroidism, wasting diseases, and periods of fasting. This means that the amount of nitrogen excreted from the body is greater than the amount of nitrogen ingested.[3] A negative nitrogen balance can be used as part of a clinical evaluation of malnutrition.[4]

Nitrogen balance is the traditional method of measuring dietary protein requirements.[5] Determining dietary protein requirements using nitrogen balance requires that all nitrogen inputs and losses are carefully collected, to ensure that all nitrogen exchange is accounted for.[6] To control nitrogen inputs and losses, nitrogen balance studies usually require participants to eat very specific diets (so total nitrogen intake is known) and stay in the study location for the duration of the study (to collect all nitrogen losses). Exercise also affects nitrogen excretion [7]. Thus nitrogen balance studies usually require controlled conditions to obtain reliable results. Because of these conditions, it can be difficult to study the dietary protein requirements of various populations using the nitrogen balance technique (e.g. children).[8]

Dietary nitrogen, acquired from metabolizing proteins and other nitrogen-containing compounds, has been linked to changes in genomic evolution. Species that primarily obtain energy from metabolizing nitrogen-rich compounds use more nitrogen in their DNA than species that primarily break down carbohydrates for their energy[citation needed]. Dietary nitrogen alters codon bias and genome composition in parasitic microorganisms.[9]

See also

References

  1. ^ Dickerson, Roland (April 2016). "Nitrogen Balance and Protein Requirements for Critically Ill Older Patients". Nutrients. 8 (4): 226. doi:10.3390/nu8040226. PMC 4848694. PMID 27096868.
  2. ^ World Health Organization Protein and amino acid requirements in human nutrition. WHO Technical Report Series 935 [1]
  3. ^ "VII. Monitoring Nutrition Therapy". Archived from the original on 2011-09-28.
  4. ^ Barbosa-Silva MC (May 2008). "Subjective and objective nutritional assessment methods: what do they really assess?". Curr Opin Clin Nutr Metab Care. 11 (3): 248–54. doi:10.1097/MCO.0b013e3282fba5d7. PMID 18403920. S2CID 26831957.
  5. ^ Institute of Medicine. Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein and Amino Acids (Macronutrients). The National Academies Press: 2005
  6. ^ Rand WM, Pellett PL, Young VR (2003). Meta-analysis of nitrogen balance studies for estimating protein requirements in health adults. Am.J.Nutr 77(1):109-127.
  7. ^ Clauss, Matthieu; Burkhardt, Meike; Wöber, Sophie; Skålhegg, Bjørn Steen; Jensen, Jørgen (21 February 2024). "Effect of five hours of mixed exercise on urinary nitrogen excretion in healthy moderate-to-well-trained young adults". Frontiers in Nutrition. 11. doi:https://doi.org/10.3389/fnut.2024.1345922. {{cite journal}}: Check |doi= value (help); External link in |doi= (help)
  8. ^ Elango R, Humayun MA, Ball RO, Pencharz PB (2011). "Protein requirements of healthy, school-aged children determined by the indicator amino acid oxidation method". Am. J. Clin. Nutr. 94 (6): 1545–1552. doi:10.3945/ajcn.111.012815. PMID 22049165.
  9. ^ Seward EA and Kelly S (Nov 2016). "Dietary nitrogen alters codon bias and genome composition in parasitic microorganisms". Genome Biology. 17 (226): 226. doi:10.1186/s13059-016-1087-9. PMC 5109750. PMID 27842572.
  • "Test Definition: NITF". Mayo Clinic Laboratories. (with clinical information & interpretation related to nitrogen balance and its clinical testing)
Retrieved from "https://en.wikipedia.org/enwiki/w/index.php?title=Nitrogen_balance&oldid=1213328693"