Live Healthy Live Well

There are two main types of fat found in mammals: white and brown. White fat has three primary functions: to insulate, to cushion, and to provide energy. Brown fat provides heat/warmth in newborns, because infants can’t shiver to keep warm. Instead, they burn brown fat for warmth; it is literally a heat organ. Hibernating animals also have high levels of brown fat.

A quarter (25%) of an infant’s body mass is brown fat, which is located on the back, primarily along the top half of the spine up towards the shoulders. In adults, how much you have and where it is located varies. Adults have much more white fat than brown fat. Whatever brown fat they have is usually located in the upper chest and the front part of the neck.

Why differentiate between the two? Brown fat, essentially, is awesome. It contains heat-producing cells of mitochondria and – unlike white fat – is metabolically active, meaning it burns calories. Brown fat gets its dark color from its high iron content.

Adults who have larger quantities of brown fat tend to be thinner because of this advantage. Brown fat is more like muscle than like white fat. Experts don’t know exactly how to help adults increase their brown fat stores in the body, but we know that always covering up or spending all of our time indoors in temperature controlled environments decreases over time the amount of brown fat in our bodies.

Parent think they are being solicitous when they sneak into their infant’s bedroom at night to “re-cover” them, but it may be beneficial metabolically for children to sleep in a cooler environment. If you touch their hands, they feel warm. However, constantly piling on blankets and/or clothing is detrimental as the brown fat stores will gradually dissipate.

Remember–brown fat is activated by cold. Spending time in the cold may enable you to grow new brown fat cells according to a study conducted by the National Institutes of Health. So keep that thermostat at a lower temperature during the winter. Take long walks out-of-doors. It will help you burn more calories, as well as save money on your utility bills.

Sources:

Healthline (2018). Brown fat: What you should know. https://www.healthline.com/health/brown-fat#1

Rutgers University (2019). Why brown fat is good for people’s health. https://www.sciencedaily.com/releases/2019/08/190821135238.htm

National Institutes of Health (2019). How brown fat improves metabolism. https://www.nih.gov/news-events/nih-research-matters/how-brown-fat-improves-metabolism

New England Journal of Medicine (1984). Thermogenesis in Brown Adipose Tissue as an Energy Buffer – Implications for Obesity. https://www.nejm.org/doi/full/10.1056/NEJM198412133112407

Written by:  Donna Green, Family and Consumer Sciences Educator, Ohio State University Extension, Erie County, green.308@osu.edu

Reviewed by:  Beth Stefura, Family and Consumer Sciences Educator, Ohio State University Extension, Mahoning County, stefura.2@osu.edu