Editing Body mass index (section)

==Relationship to health==
A study published by ''[[Journal of the American Medical Association]]'' (''JAMA'') in 2005 showed that ''overweight'' people had a death rate similar to ''normal'' weight people as defined by BMI, while ''underweight'' and ''obese'' people had a higher death rate.<ref>{{cite journal | vauthors = Flegal KM, Graubard BI, Williamson DF, Gail MH | title = Excess deaths associated with underweight, overweight, and obesity | journal = JAMA | volume = 293 | issue = 15 | pages = 1861–1867 | date = April 2005 | pmid = 15840860 | doi = 10.1001/jama.293.15.1861 | doi-access =  }}</ref>

A study published by ''[[The Lancet]]'' in 2009 involving 900,000 adults showed that ''overweight'' and ''underweight'' people both had a mortality rate higher than ''normal'' weight people as defined by BMI. The optimal BMI was found to be in the range of 22.5–25.<ref>{{cite journal | vauthors = Whitlock G, Lewington S, Sherliker P, Clarke R, Emberson J, Halsey J, Qizilbash N, Collins R, Peto R | title = Body-mass index and cause-specific mortality in 900 000 adults: collaborative analyses of 57 prospective studies | journal = Lancet | volume = 373 | issue = 9669 | pages = 1083–1096 | date = March 2009 | pmid = 19299006 | pmc = 2662372 | doi = 10.1016/S0140-6736(09)60318-4 }}</ref> The average BMI of athletes is 22.4 for women and 23.6 for men.<ref>{{cite journal | vauthors = Walsh J, Heazlewood IT, Climstein M | title = Body Mass Index in Master Athletes: Review of the Literature | journal = Journal of Lifestyle Medicine | volume = 8 | issue = 2 | pages = 79–98 | date = July 2018 | pmid = 30474004 | pmc = 6239137 | doi = 10.15280/jlm.2018.8.2.79 }}</ref>

High BMI is associated with [[diabetes mellitus type 2|type&nbsp;2 diabetes]] only in people with high serum [[gamma-glutamyl transpeptidase]].<ref name="pmid17478563">{{cite journal | vauthors = Lim JS, Lee DH, Park JY, Jin SH, Jacobs DR | title = A strong interaction between serum gamma-glutamyltransferase and obesity on the risk of prevalent type 2 diabetes: results from the Third National Health and Nutrition Examination Survey | journal = Clinical Chemistry | volume = 53 | issue = 6 | pages = 1092–1098 | date = June 2007 | pmid = 17478563 | doi = 10.1373/clinchem.2006.079814 | doi-access = free }}</ref>

In an analysis of 40 studies involving 250,000 people, patients with coronary artery disease with ''normal'' BMIs were at higher risk of death from cardiovascular disease than people whose BMIs put them in the ''overweight'' range (BMI 25–29.9).<ref>{{cite journal | vauthors = Romero-Corral A, Montori VM, Somers VK, Korinek J, Thomas RJ, Allison TG, Mookadam F, Lopez-Jimenez F | title = Association of bodyweight with total mortality and with cardiovascular events in coronary artery disease: a systematic review of cohort studies | journal = Lancet | volume = 368 | issue = 9536 | pages = 666–678 | date = August 2006 | pmid = 16920472 | doi = 10.1016/S0140-6736(06)69251-9 | s2cid = 23306195 }}</ref>

One study found that BMI had a good general correlation with body fat percentage, and noted that obesity has overtaken smoking as the world's number one cause of death. But it also notes that in the study 50% of men and 62% of women were obese according to body fat defined obesity, while only 21% of men and 31% of women were obese according to BMI, meaning that BMI was found to underestimate the number of obese subjects.<ref name="RomeroCorral2008"/>

A 2010 study that followed 11,000 subjects for up to eight years concluded that BMI is not the most appropriate measure for the risk of heart attack, stroke or death. A better measure was found to be the [[waist-to-height ratio]].<ref>{{cite journal | vauthors = Schneider HJ, Friedrich N, Klotsche J, Pieper L, Nauck M, John U, Dörr M, Felix S, Lehnert H, Pittrow D, Silber S, Völzke H, Stalla GK, Wallaschofski H, Wittchen HU | title = The predictive value of different measures of obesity for incident cardiovascular events and mortality | journal = The Journal of Clinical Endocrinology and Metabolism | volume = 95 | issue = 4 | pages = 1777–1785 | date = April 2010 | pmid = 20130075 | doi = 10.1210/jc.2009-1584 | doi-access = free }}</ref> A 2011 study that followed 60,000 participants for up to 13 years found that [[waist–hip ratio]] was a better predictor of ischaemic heart disease mortality.<ref name= "MørkedalRomundstad2011">{{cite journal | vauthors = Mørkedal B, Romundstad PR, Vatten LJ | title = Informativeness of indices of blood pressure, obesity and serum lipids in relation to ischaemic heart disease mortality: the HUNT-II study | journal = European Journal of Epidemiology | volume = 26 | issue = 6 | pages = 457–461 | date = June 2011 | pmid = 21461943 | pmc = 3115050 | doi = 10.1007/s10654-011-9572-7 }}</ref>