You can find body fat all over the body: under the skin (which we call subcutaneous fat) but also on your kidneys, inside your liver, and in small quantities in your muscular tissue (visceral fat). But where does it come from? Why do we need it, and what are the best ways to get rid of it?
The main role of body fat is to store energy. Adult males often tend to store body fat in the chest, abdomen and buttocks. As for women, they tend to store it in their breasts, hips, waist and buttocks. Up until the 1990s, we believed that these parts of the body stayed “passive” and were useful for storing energy, “just in case” of difficult times -for example, for our ancestors in the case of unsuccessful hunting and gathering. However, we now know that it is a little more complicated than that.
Around 500 grams of fat contains around 3,500 calories of stored energy. But how can the body use such fat, and what else is it used for?
What burns the most energy? Our brains use around 20% of the calories we burn in a day, despite the fact that it makes up only 2% of our total body weight. Although solving a very complicated mathematical problem increases the absorption of sugar in the brain, however it is not the best option for weight loss. The organs such as the heart, the lungs and the liver make up 5% of our body weight, but all together they consume around 50% of our daily calories. The rest is shared between the tissues and muscles, while the excess is stored.
In fact we have more than one type of fat in our bodies: there is white fat and brown fat. The main type of fat cells are called white adipose tissue, so called because it has a milky yellow colour. The other type of fat is called brown adipose tissue, which in reality is an orange to reddish colour. Brown fat is generally situated in the neck, the shoulders and around the collarbone, and doesn’t behave in the same way as white fat, but more like a muscle. Thus, when while white fat stores energy and is associated with weight gain, brown fat is thermogenic, which means it increases body heat and burns energy from the white fat. The higher the reserves of brown fat, the higher the level of thermogenesis of white fat.
So how much fat do we need? It is important to remember that your ideal body fat percentage is very different to that of your friends. The quantity of body fat we have depends on many things that are out of our control. Age, bone density, gender and genetics all play important roles in the amount of body fat we have. Overall, too much body fat is associated with health problems such as type 2 diabetes, heart disease and certain types of cancer. But too little body fat can also be problematic. The human body needs a certain percentage of body fat in order to function properly. For women, their body fat should not go below 14%, while for men the lower threshold is at around 8%.
So what should you do to lose excess fat, outside of eating healthily? As well as avoiding animal fats, you also need to do cardio exercises (walking, cycling, jogging, etc.), which are good for the body. These exercises reduce the risk of heart disease, but are not the best choice if you want to reduce body fat. If your only goal is fat burning, muscle building is best, and burns fat better than cardio. By lifting weights for just 15 to 20 minutes twice a week, you can see positive effects on your resting metabolic rate, your blood pressure and your sensitivity to insulin. The ideal is to combine cardio and muscle building.
A few bonus tips: drink 100-150 mg of green tea or black coffee on an empty stomach, and follow it with a 30 minute cardio or strength-building session in the morning. The caffeine will mobilise the fatty acids in the adipose tissue. Finish off with a shower alternating hot and cold temperatures: 10 seconds of hot water and 20 seconds of cold water, repeated 10 times. This will activate thermogenesis of the brown fat.
But afterwards, where does the fat go? Researchers studying this biochemical process have observed fat molecules throughout the body to attempt to answer this question. The response: we breathe it out. If you lose 10 kilograms of body fat, 8.4 of these kilograms will be released in the form of carbon dioxide (CO2) when you breathe out. The rest is evacuated via urine, sweat or -we don’t wish it on you -tears.