Brown fat (or brown adipose tissue) is found in hibernating mammals, its function being to increase tolerance to the cold. It is also present in newborn humans. In adult humans it is more rare and is known to vary considerably with ambient temperature. RouthierLabadie2011 analysed data on 4,842 subjects over the period 2007-2008, of whom 328 (6.8%) had brown fat. Brown fat mass and other demographic and clinical variables were recorded. The purpose of the study was to investigate the factors associated with brown fat occurrence and mass in humans.
data("brownfat")A data frame with 4842 observations on the following 14 variables.
sex1=female, 2=male
diabetes0=no, 1=yes
ageage in years
dayday of observation (1=1 January, ..., 365=31 December)
exttempexternal temperature (degrees Centigrade)
seasonSpring=1, Summer=2, Autumn=3, Winter=4
weightweight in kg
heightheight in cm
BMIbody mass index
glycemyglycemia (mmol/L)
LBWlean body weight
cancerstatus0=no, 1=yes, 99=missing
brownfatpresence of brown fat (0=no, 1=yes)
bfmassbrown fat mass (g) (zero if brownfat=0)
Ouellet, V., Routhier-Labadie, A., Bellemare, W., Lakhal-Chaieb, L., Turcotte, E., Carpentier, A.C. and Richard, D., (2011). Outdoor temperature, age, sex, body mass index, and diabetic status determine the prevalence, mass, and glucose-uptake activity of 18F-FDG-detected BAT in humans. The Journal of Clinical Endocrinology & Metabolism, 96(1), pp.192-199.