New research indicates that a cup of coffee, or three, could help you lose weight. A new study out Monday morning in the journal Scientific Reports finds coffee can stimulate "brown fat" — the fat in your body that keeps you warm by burning calories.
On "CBS This Morning" Dr. David Agus explained what the finding means for our understanding of metabolism.
What is "brown fat"?
Brown adipose tissue (BAT), or "brown fat" (also known as "good fat"), can generate heat and metabolize macronutrients (i.e. glucose-heavy foods like honey and dried fruit) by burning calories. White adipose tissue (WAT), or "white fat," meanwhile, stores calories that haven't been burned.
"Normal fat stores energy. And brown fat has lots of mitochondria and iron (which is why it's brown), and its purpose is to generate heat," said Dr. Agus. "Basically, that changes metabolism and actually changes the cholesterol or fat profile in your blood.
"We didn't even know brown fat existed until 10 years ago. Babies have brown fat because they can't shiver and create heat. We found brown fat in adults, predominantly in the upper chest."
The study shows that a cup of coffee or caffeine can actually stimulate brown fat to make heat. "We all have that warm feeling after we drink a cup of coffee, because we're stimulating that brown fat," he said. "It's important and interesting that we actually know the mechanism now.
"The goal is to stimulate brown fat. Exercise stimulates brown fat. Good sleep stimulates brown fat. And now we know caffeine or coffee can do the same."
How much of a good thing?
"First of all, up to three cups a day may have a health benefit, [with] no detriment," Dr. Agus said. "Don't do more. More isn't better.
"What I also want to push is, no coffee after 1:00 or 2:00 p.m. Caffeine's half-life is six hours. If you have a 1:00 [cup], it's only going to be half the level by 7:00 at night. Even if you sleep, it's not going to be the deep restful sleep with caffeine on board."