One thing about British summer I have learned since I moved to this country is that… it doesn’t last. A couple of weeks of heatwave, and then the temperature would just drop like nobody’s business. Last week I was either getting rained on while walking to work, or having to wrap up like it’s already autumn.
But don’t feel bad now, because apparently the cold weather comes with its own perk for us who’s trying to lose weight.
We have learned about fat tissue in our body, and we know that it is actually a form of energy storage from our excess calories. We’ve also learned already that there are subcutaneous fat underneath our skin, and visceral fat inside our belly. But, this is something that I just learned… we have two different type of fat, based on their colours… Yes, you’ve guessed that right. The white fat and the brown fat.
White fat is how our body storage energy in the form of oil droplets. When we are consuming less calories than what we are using, we will convert this white fat into energy.
When we are talking about fat in general, we are actually referring to this kind of fat. Mainly because this is the kind of fat that most adults have.
When we were babies, we have about 5% of brown fat in our body to keep us warm. This is because brown fat is the type of fat tissue which can be converted into heat, instead of into energy, and as a baby we will need this because we don’t know yet how to shiver. Unfortunately, as we grow up, we also lose brown fat, and left with only white fat.
Brown fat, unlike white fat has smaller oil droplets, and have more blood supply (hence the brownish colour). And, because of how it works, this is why brown fat is called good fat, and white fat is called bad fat.
No… don’t look at me. I did not make that up. Even NHS has looked into this, because of the possibility of it being helpful in fighting obesity and diabetes.
Unlike white fat, we don’t need to diet to lose it. All we need to to do is to be exposed to cold.
But YOU said we don’t have brown fat anymore!! I heard you screamed in frustration from the other side of the internet. Yes… I did say that, but apparently, we can turn some of our white fat into brown.
The white fat which is turning brown after a stimulation is called the beige fat.
Some studies (2018) have shown that you can brown your white fat through some chemical you can get from food, like capsaicin (what makes chilli pepper hot) for example has been tested in human. Another study (2009) also said that an exposure to a cooler temperature which is enough to make you shiver for two hours a day, and cold shower are enough to turn your white fat brown.
This is where I think that it needs more study. We have learned how white fat works, so we can calculate our calorie consumption and amalgamate it with our CICO routine. I haven’t yet seen how we can calculate the burning level of brown/beige fat. Or how it will affect our BMR/RMR.
We have learned that some food like celery is considered negative calorie food, because the amount of calories to digest it is more than the calorie in the food itself. BUT, how about these food which brown our fat? How much are they converting?
As much as I would like to rely on this new knowledge about brown fat, I think this study is still too premature to be introduced as a practical solution, unless you have an accompanying medical team which would help you to check your condition routinely. It might help losing weight during the winter, for example, but the significance of it is probably negligible as you might want to have some extra booze on the Christmas parties.
However… I do hope that this is helpful. There are links to the publications about this research below too if you are interested to read more.
Dietary polyphenols and their roles in fat browning (Brown fat with food)
Brown Adipose Tissue Improves Whole-Body Glucose Homeostasis and Insulin Sensitivity in Humans (Brown fat with diabetes)
Functional Brown Adipose Tissue in Healthy Adults (brown fat with cold temperature)