There are two types of fat cells: white and brown. White fat cells are for storage only; they accept free fatty acids from the bloodstream and bind them into triglycerides, and take triglycerides apart and put the fatty acids back into the bloodstream. This process is highly regulated by the presence or absence of insulin.
Brown fat cells not only store fatty acids, but also metabolize them, producing heat in the process. Hibernating animals have a lot of brown fat, which metabolizes their fat store during estivation. The presence of carbohydrate in their diet, especially glucose (as in ripe berries in autumn), stimulates the growth of brown fat; by springtime, their brown fat stores are depleted, and their metabolism returns to normal.
Human babies are born with deposits of brown fat in certain locations; it provides enough warmth that they don’t need to shiver to stay warm. As they grow, these brown fat deposits turn into white fat, which is why children do shiver.
The key point is that under the proper stimulus, fat cells can change from white to brown, or vice versa. It has been shown in certain studies that under the right circumstances, the human body will change some white fat into brown fat, and the brown fat will metabolize fat simply to use it up, simply wasting the heat produced. That’s what Ross didn’t know. And what I didn’t know was the bit he posted about brown fat’s being activated (or white fat being turned into brown) by exposure to cold.
Why are the two types called “white” and “brown”? It’s simply that the former looks noticeably whiter, and the latter, noticeably browner than the other.
I told her that’s just water that replaced the fats she lost and she should ditch the scale and try using her clothes to monitor.
so I will just wait until I’m in the uk and life will be easier
I do eat that stuff of course and was wondering if any non middle eastern saw me eating it, will probably get disgusted