Intermittent fasting (IF) is an eating cycle in which you alternate between periods of eating and fasting. The most common one requires an overnight fast window of 12-16hs (or more), where you don’t ingest anything other than water, black coffee or tea.
Contrary to common practices that involve late dinner, early breakfast and frequent snacking, intermittent fasting promotes a routine that is much more in synch with our physiology. Humans are still geared to a feast and famine pattern of energy intake characteristic of our hunter-gatherer homo sapiens ancestors.
The ancient practice of IF is actually backed by science and has numerous health benefits:
When we go without food for a certain amount of time, insulin goes down and glucagon goes up, turning on autophagy. From the Greek auto (self) and phagein (to eat), which literally means “to eat oneself”, autophagy is the way in which the body gets rid of old and damaged cell parts.
It stimulates growth hormone, prompting the body to regenerate.
It improves insulin sensitivity and weight control lowering diabetes risk (provided you follow some basic rules during the fed phase), without lowering the resting metabolic rate.
It may be neuro and cardio-protective.
It allows the GI tract to take a break and repair, resulting in improved digestion and absorption of nutrients.
It helps to improve energy, cognition and memory.
Easy does it
Very important: If you are pregnant or have a medical condition, intermittent fasting may not be right for you; seek advice from your healthcare provider.
If you decide to give it a try, bear in mind that if not done correctly, intermittent fasting can backfire and cause hormonal imbalance. Women are particularly sensitive to signals of starvation, prompting the body to produce more leptin and ghrelin (hunger hormones).
Some important considerations:
Go gradual (on fasting window and fasting days).
Adjust calories intake based on the intensity of your workout.
Drink plenty of water.