When aiming to lose belly fat, some people will start adding hundreds of crunches to their fitness routine, hoping to see a six pack magically pop out after a few weeks. However, it is not the way it works, you can have the most developed abdominals in the world, you will never see them if they are covered with a layer of fat.
The second widespread mistake is to start a restrictive diet and commit to an exhausting training routine, with lots of long duration cardio training sessions. Not only is it useless, but it is also counterproductive as it can increase the abdominal fat you want to get rid of.
In order to address the issue properly, it is essential to understand what abdominal fat is and which mechanisms are involved in fat storage and fat loss in this part of the body.
What is abdominal fat?
The first thing you need to know is that there are two types of abdominal fat.
- Subcutaneous abdominal fat
It is just under the skin and above the abdominal muscles. You can palpate it easily, and it is the one that forms belly bulges.
Subcutaneous fat is the most difficult to eliminate for several reasons: it is less irrigated in blood vessels, less sensitive to the catecholamines (adrenaline, norepinephrine) that allow the fat to be released. Moreover, it is more sensitive to insulin, which means that low levels of insulin are enough to store fat and prevent it from being released and burnt. It also contains a greater number of alpha-adrenergic receptors that promote fat storage.
- Visceral fat
If your belly is bulky but hard on the surface, your belly fat is visceral. It is under the muscles and not palpable. This type of body fat is the most harmful to your health as it is around vital organs. It secretes inflammatory components and induces increased risks of cardiovascular diseases, diabetes, certain cancers, etc. A study published by the European Society of Cardiology proved that people with normal BMI but having a large amount of visceral fat were much more at risk of dying of cardiovascular diseases than obese people with a lower waist to hip ratio.
In addition to its negative effects on health, the components it releases increase insulin and leptin resistance. It’s a vicious circle: insulin and leptin resistance increases abdominal fat which causes more insulin and leptin resistance, etc.
The good news is that visceral fat is easier to eliminate than subcutaneous fat. It is more irrigated in blood vessels, more sensitive to catecholamines and it has more beta-adrenergic receptors (they promote fat release to produce energy).
The culprits: cortisol and insulin
The first hormone that comes to mind when talking about belly fat is cortisol, also called the abdominal fat hormone. However, it would be unfair to demonize this hormone and give it full responsibility for belly fat storage. The role of hormones in fat storage and fat loss mechanisms must be understood in a relative way: we must consider the level of one hormone compared to others and how they interact. Cortisol can promote abdominal fat or fight against it depending on the hormones to which it will be associated. The combination we want to avoid is that of cortisol and insulin.
For a better understanding, let’s explain some survival mechanisms.
Cortisol is secreted when the body is exposed to stress. Its goal is to increase the level of sugar in the blood to provide the body with the energy needed to react quickly and effectively in case of danger. The liver increases its production of glucose and releases it into the bloodstream. The muscles and the fat also provide the body with amino acids and triglycerides. The body will therefore use sugar, fat and muscle.
The problem is, originally the kind of stress situations we are programed to react to was fighting or fleeing a wild animal, hunting, surviving famine… Nowadays, we are not faced to such situations anymore and the level of physical activity is much lower, but our bodies don’t tell the difference and the same mechanisms are involved. The body needs to get rid of the unused sugar and this will be done with the help of increased insulin secretions. Insulin tells the body to store this sugar in the fat cells and to block the fat release. The more insulin, the less fat the body burns and the more it will have to turn to the muscle to support long physical activities.
In addition to promoting fat storage, the combination of cortisol and insulin will influence the location of this storage. Our body will store fat where it can be used as quickly as possible in case of any emergency, the closest to the liver, which is to say in the abdominal area.
Things will get even worse if the stress is chronic: the body gets used to this situation and needs more and more secretions of cortisol and insulin to be able to generate the same response.
Factors that promote cortisol secretions are situations that put the body in a state of physiological stress:
- Psychological stress
- Hectic pace of life
- Lack of sleep
- Exhausting long duration, medium intensity cardio training routines
- Restrictive diets
- Hormonal disorders such as PCOS and thyroid for women or lack of testosterone for men (which are influenced by the five first points)
As for insulin, it is favored by:
- Starchy foods
- The combination of fatty and sugary foods
- But also the increase in the amount of body fat.
Your allies against abdominal fat
Like cortisol, catecholamines (adrenaline, norepinephrine) are hormonal messages generated by the adrenals in response to a stress situation, in order to allow humans to fight or flee. They help the body release the fat from the cells and transform it into energy by activating the lipase, a hormone that is found in the adipose tissue.
In order to produce energy as quickly as possible, it is necessary to use the nearest source to the liver: the abdominal fat. That’s when things become interesting and that’s the reason why this part of the body contains a large number of beta-adrenergic receptors that are very receptive to adrenaline.
These receptors that are found in fat cells membrane act like small locks. By finding the right keys, you can open the door and allow the fat to be released and burnt. In this case, the appropriate keys are catecholamines and, more particularly, adrenaline. Once adrenaline has opened the lock that is the adrenergic receptor, it will trigger a series of physiological reactions that will burn fat and preserve muscle mass.
So how do we increase adrenaline? For thousands of years it has been the response to stress situations such as fleeing or fighting an animal or surviving a period of famine. But unless you have a saber-toothed tiger in your garden, you will have to find another activity that will generate an equivalent level of stress. Do you think that running, whether it lasts 20 or 90 minutes, will do the trick? Obviously, no. This is the reason why we will have to go for intense physical activities.
- Growth hormone and testosterone.
As previously explained, cortisol can also help burn fat when insulin levels are low and when it is associated with the good hormones: testosterone and growth hormone.
After having an intense activity that has allowed you to escape a stressful situation, the body triggers the secretion of hormones such as testosterone and growth hormone to repair damaged tissues and direct the use of energy towards the metabolism of fats while preserving or even building muscle. The repair mechanisms of these two hormones rebuild the body so that it remains thin, fast and stronger to be able to respond to another danger.
Growth hormone acts at different levels. Among other things, it allows the increase in muscle mass but also blocks the negative action of insulin. When growth hormone is released by the pituitary gland and enters the bloodstream, it is absorbed by the liver, which transforms it into IGF-1 (Insulin-like Growth Factor 1). This hormone will prevent insulin from storing fat in the cells and will cause the body to use fat first to transform it into energy.
As for testosterone, if it also allows to build muscle, it has the particularity of increasing the number of beta-adrenergic receptors, our dear fat cell locks.
You may think that you just have to get rid of cortisol altogether. But things are not that simple because the fat burning action of growth hormone and testosterone is increased tenfold when they are combined with a reasonable amount of cortisol. Let’s remind that this hormone, which aims to respond to stress, can use the liver, muscles and fat stores to create energy. The challenge will be to ensure fat stores are used instead of muscles. This will be done by limiting the action of insulin and promoting the secretions of growth hormone and testosterone. Hence, the importance of choosing high intensity physical activities.
What changes are to be made?
It is necessary to find the hormonal balance to limit the cortisol without removing it completely and limit insulin action as much as possible while promoting the secretions of adrenaline, growth hormone and testosterone.
It is not about eating less and training more, but eating the right food, lowering stress, sleeping more and training smarter.
- No more restrictive diets.
- Adopt a low carb diet, not more than 150 g of carbs a day.
- Avoid sugar.
- Increase your healthy fat intake as well as protein and fiber (non-starchy vegetables).
- Sleep at least 7 hours each night and go to bed around 10 pm at the latest.
- Allow yourself 30 minutes of relaxation each day, with no screen. Go for a slow-paced walk, enjoy a pleasant talk, play, take a bath, stretch, meditate or read a book…
- Avoid long duration medium intensity cardio sessions like running.
- Go for intense physical activities such as HIIT, sprints, CrossFit, strength training with heavy weights, metabolic chains and allow yourself at least one or two rest days each week.