Intermittent fasting is a popular way of eating that involves restricting food intake for a certain period of time.
Some people choose to fast for 12 hours a day, while others may fast for two to three days.
Many people find it easier to skip a meal completely rather than eat a smaller portion of food. This is because food naturally releases dopamine, a neurotransmitter that plays a role in motivation and seeking. When we eat, our dopamine levels increase, which can lead us to want more food.
However, fasting can also lead to an increase in dopamine release.
When we deprive ourselves of food and then finally eat, the dopamine release is heightened, especially if we have been very hungry.
This is because dopamine receptors become more sensitive when they haven’t been exposed to much dopamine.
Some people who practice intermittent fasting report that they enjoy the clear state of mind they experience while fasting, and may even extend their fasting periods in order to experience this state.
Fasting can be seen as a way to attach dopamine to the effort and strain of deprivation rather than to the reward of food.
It’s important to note that the subjective knowledge of the benefits of fasting, such as improved blood lipid profiles and insulin sensitivity, can also serve as reinforcing factors that amplify the release of dopamine.
However, it’s important to be mindful of the potential for fasting to become an unhealthy obsession or to compensate for unhealthy eating habits. It’s always important to consult a healthcare professional before making any changes to your diet.
“One straightforward example of learning to attach dopamine to effort and strain as opposed to a process or a reward that naturally evokes dopamine release is so-called intermittent fasting. I know this is very popular nowadays. Some people like to do intermittent fasting, some people don’t. Some people have a 12-hour feeding window every 24 hours. Some people do long fasts of two to three days even.
I personally don’t monitor a feeding window with a lot of precision. I tend to skip one meal a day, either breakfast or lunch, and then I eat the other two meals of the day depending on which meal I skip. So it’s either breakfast, lunch, and maybe a little something in the evening, or I’ll skip breakfast and do lunch and dinner and so on.
Many people are now eating this way in part because many people find it easier to not eat at all than to eat a smaller portion of some food. And that has everything to do with the dopamine reward evoking properties of food. When we ingest food or when we are about to ingest food, our dopamine levels go up. And typically when we ingest food, if it evokes some dopamine release, then we tend to want even more food.
Remember, dopamine’s main role is one of motivation and seeking. And what dopamine always wants more of is more dopamine, more activity or thing that evokes more dopamine release.
Well, let’s just look at fasting from the perspective of dopamine schedules and dopamine release and peaks and baselines. Typically when we eat, we get dopamine release, especially when we eat after being very hungry. If you’ve ever gone camping or you’re very, very hungry, the food tastes that much better. And that’s actually because of the way that deprivation states increase the way that dopaminergic circuits work.
Our perception of dopamine is heightened when the receptors for dopamine have not seen much dopamine lately. They haven’t bound much dopamine. So when you fast, fast, fast, fast, fast, and then you finally eat, it evokes more dopamine release. So this is the big reward that comes at the end, even bigger because you deprived yourself. This is true for all rewarding behaviors and activities.
By the way, the longer you restrict yourself from that activity, the greater the dopamine experience when the dopamine is finally released because of an up-regulation of the receptors for dopamine. But I just spent five minutes or more telling you that you should avoid too much reward at the end and you should actually focus on the dopamine that you can consciously evoke from the deprivation strain and effort.
And in fact, this is what happens for many people that start doing fasting and take a liking to it. Many people say that their state of mind when they fast is clear, that they actually start to enjoy the period of fasting. In fact, some people start pushing out their eating window or skipping entire days of eating more and more in order to get deeper into that state of mind where surely it’s not just dopamine, but dopamine is released.
They will track their clock. Oh, I’ve been fasting 12 hours, 16 hours, et cetera. They are starting to attach dopamine release or create dopamine release from the deprivation, not from the food reward itself. And this, I think, makes it an interesting practice and one that certainly has been practiced for centuries in different cultures and different religions of deliberately restricting food, not just to increase the rewarding properties of food itself but also to increase the rewarding properties of deprivation.
And I should emphasize that a lot of the subjective aspects of the knowledge of the benefits of fasting serve as reinforcing dopamine amplifying aspects to fasting, meaning if somebody does intermittent fasting and they are deep into their fast and they’re telling themselves, oh, my blood lipid profiles are probably improving and my glucose management is probably improving, my insulin sensitivity is going up and I’m going to live longer, all these things that have some basis from animal studies and some basis or not from human studies, it’s all kind of still in emerging literature, but it does seem to be pointing in that direction that fasting can encourage things like autophagy, the engulfment of dead cells and things of that sort.
Well, as people tell themselves these things, they are enhancing the rewarding properties of the behavior of fasting. And so this is a salient example of where knowledge of knowledge can actually help us change these deep primitive circuits related to dopamine. And this illustrates how the forebrain, which carries knowledge and carries interpretation and rational thought, can be used to shape the very circuits that are involved in generating reward for what would otherwise just be kind of primitive behaviors, hardwired behaviors. And that’s the beauty of these dopamine circuits. And that’s the beauty of dopamine.”
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