How ‘brown fat’ could be your key to losing weight this winter
Staying cool may be the key to losing weight this winter, thanks to a special type of fat.
Unlike white fat, which acts as an energy reserve for the body, brown fat converts calories into heat when cold.
Theoretically, turning down the thermostat or swimming in cold water could increase the benefits of brown fat on our bodies.
But experts say it may not be as simple as diving into cold water to get our brown fat under control.
Since babies don’t have enough muscles to shiver, brown fat is abundant, and brown fat helps keep them warm.
Fat cells do this by housing large numbers of energy-producing mitochondria within the cell. Types of mitochondria inside fat cells can convert calories from food into heat.
The caveat here is that adults have much less brown fat than babies, making it harder for us to reap the benefits of converting calories.
“Adults have relatively small amounts of brown fat and there’s no real way to increase that number. You can use the brown fat that’s already there but it won’t have a dramatic impact on energy balance,” said Martin Whyte, associate professor of metabolic medicine at the University of Surrey. Independent.
“But when the white fat tissue doesn’t turn into brown fat but turns beige, you can do what’s called ‘browning.’ It can act a bit like brown fat by recruiting white fat cells, and the difference in color comes from the mitochondrial content, of course.”
It is possible to trigger browning of fat cells by being in the cold, but the cold must be constant. Professor Whyte explains that taking a cold shower in the morning will not be enough.
“Continuous exposure to 16-degree heat for at least a few hours a day will cause fat cells to brown,” he added.
Cold activates the fight-or-flight response in the hypothalamus gland, which leads to stimulation of your sympathetic nervous system. This releases the neurotransmitter noradrenaline, which binds to the receptors of these cells and causes browning.
But experts question whether this browning of fat cells actually leads to weight loss.
“If you don’t turn the heater on in the winter you’ll probably increase your brown fat and cause the white fat to brown too much, but you could also be losing weight by literally shivering,” Prof Whyte said.
Our behavior also changes when we are exposed to consistent levels of cold, causing us to eat more, which causes us to gain weight.
“Prolonged exposure to cold certainly increases your brown fat and causes browning, but after all this it is questionable whether there is a net gain due to the change in your behaviour,” Professor Whyte added.
A better option may be medication to achieve the same results while avoiding cold. Prof Whyte explained how the drugs can replicate the binding of noradrenaline to cells’ receptors and bypass the cold exposure part.
However, since these drugs stimulate the sympathetic nervous system, they may also have other side effects such as increased heart rate.
Although there is a relationship between browning of fat cells and weight loss, Adam Collins, associate professor of nutrition at the University of Surrey, emphasized that causality does not mean correlation.
“If you compare our habits to the 1980s, we’re getting warmer now and wrapping ourselves in arctic coats, so maybe we’re not exposing ourselves to enough cold,” he said. Independent.
“You don’t need to be exposed to temperatures of -10C to get the results; you can increase beige fat by exposing it to temperatures of 16C to 17C.”
He explained that there is a relationship between increasing obesity levels and the temperature at which our thermostat is located, but that this does not mean that a lack of brown fat increases obesity levels.
Prof Collins suggested that brown fat and beige fat might not be that important for regulating metabolism. Instead, those with more brown fat may be more tolerant of cold weather and produce heat.
