Neurosurgeon with 33 years of experience shares what happens in the body when you fast for 36 hours: ‘You burn fat.’
Ever wondered what happens inside your body when you fast? What if you go off food and keep a fast for 36 hours? Sounds impossible, right?
It could benefit your body more than you think, according to Dr Prashant Katakol.
In an Instagram post shared on October 24, Dr Katakol, a neurosurgeon with over 33 years of experience in neuroscience, explained what happens inside the body when one fasts for 36 hours.
What happens in your body when you fast for 36 hours?
Sharing an animated video to explain what happens inside our body when we fast and how it benefits us when we do it for 36 hours, the neurosurgeon wrote, “Your organs shift gears, the Brain stays sharp, the body burns fat, and your cells begin deep repair.”
According to the neurosurgeon, when we fast, our body goes through a process called autophagy. It helps clear out toxins and damaged proteins, causing a true internal reset. “Fasting isn’t starvation, it’s structured recovery. Your body knows how to heal if you simply give it time,” he highlighted.
The complete internal reset
According to the video shared by the neurosurgeon, which features an inner dialogue between the brain, stomach, and other organs, a fascinating story unfolds inside the body during a 36-hour fast.
During hours 0-6, your body is still running on energy from your most recent food intake. The glucose levels remain stable, insulin quietly maintains balance, and you’re not hungry yet.
In the next 6 to 12 hours, your body begins tapping into glycogen, a stored form of glucose found in your liver and muscles. It’s the first backup plan once dietary sugar runs out. Around this point, you start to feel a little hungry or tired, but nothing unbearable.
When glycogen stores are depleted, the body shifts into a fat-burning mode. The pancreas releases glucagon, signalling fat cells to release fatty acids. These are converted into ketones, a clean, efficient fuel that powers your brain and other organs.
Interestingly, your hunger hormones, especially ghrelin, begin to decrease as ketone levels rise. That’s why many people feel surprisingly clear-headed and alert during fasting, according to the clip.
In the end, with no food to digest, your body starts maintenance through a process known as autophagy. Cells begin recycling old or damaged components, inflammation decreases, insulin sensitivity improves, and your energy stabilises.
This is when fasting becomes more than just skipping meals; it becomes a rejuvenation. After 36 hours, your body is primed to absorb nutrients efficiently. Therefore, it is always advisable to break a fast with a healthy meal that provides all the essential nutrients.
