Let’s play a game: Talk to three people you know and ask them what the best practices to lose weight are. The majority of them, I can bet on it, will answer: start following a low-calorie food plan and do some exercise. Those two assumptions have been the pillars of weight loss from the dawn of time. However,  the whole affair has become more and more complicated. For some people,  reducing meals and increasing exercise is not that simple to adopt, while others take the above-mentioned pillars to the extreme. 

The idea behind calorie restriction and working out is to slowly reduce the amount of food ingested while burning fat, respectively . However, these two starting points require a strong motivation to remain focused on the goal and to be ready to face all the difficulties that a diet and a workout plan will bring. At the end of the day, it’s all about motivation.Where does motivation come from? According to a recent study, the motivation to do regular physical activity could be controlled by your hormones.

In our body there is, among others, a very important hormone called ghrelin involved in the brain reward circuits— the ones that allow us to feel satisfied and satiated after eating. We refer to this hormone as “orexigenic”,  meaning it stimulates appetite and regulates our feelings of hunger. When its levels in the bloodstream are high, it means that there is a fasting period occurring. On the contrary, low blood levels of ghrelin mean satiety perception. When speaking with someone who just jumped into a diet, they often say that the first days are the most difficult and this is all ghrelin’s fault! In fact, in the first days of a diet, ghrelin levels start to go up leaving you constantly hungry and frustrated. This is our body way of “complaining” and trying to resist, through the appetite hormone, to the depletion of energy and resources.


A hormone called ghrelin stimulates your appetite. And according to a recent study, it might control your motivation to exercise.

 It seems that ghrelin plays an important role in regulating the motivational boost related to physical exercise, in addition to regulating your appetite.  In overweight or obese people it has been demonstrated that ghrelin levels are altered and that appetite control is not efficient anymore. In the study above, obese mice were started on a series of regular workout exercises. Their ghrelin production became more and more stable and, consequently, the animals ate less and exercised more. This suggests a possible relationship between motivation to exercise and feeding regulating hormones such as ghrelin. 

What is the take-home message for us humans?

  1. Practice portion control and reduce meal frequency (through intermittent fasting!) to stabilize your levels of ghrelin
  2. Avoid continuous food intake – eat only at mealtimes
  3. After a period of fasting, let yourself get carried away by ghrelin and do some exercise

Hunger, indeed, seems to play the crucial role in ghrelin production, increasing motivation for intentional exercise. In this way, whether you are overweight or obese, you would reduce weight, re-set your ghrelin levels, decrease your food cravings and keep the motivation for your daily workout routine.

Reader’s challenge: Start with eating only at breakfast, lunch and dinner time, or if you are particularly motivated, start fasting by skipping breakfast a few times per week. Then add in some exercise, such as a long walk or a morning yoga. Feel your body!