One question I get asked often is when does autophagy start during a fast? And the answer isn’t always so simple. Instead of thinking of autophagy like an on and off switch, I like to think of it as a dial. Autophagy is always “on” to some degree, but the dial is turned down while eating and when insulin is higher, and then the dial can turn up during a fast.
Experts can’t quite agree on the optimal length of a fast for autophagy benefits and the data available is limited. The autophagy fasting sweet spot might be very individual and might have to do more with the body than the clock, so to speak. Some may see that spike in autophagy after only 8 hours of fasting and for others, it might be closer to the 16 to 18-hour mark. Why is this? We all have different metabolisms, different degrees of metabolic flexibility and are under different levels of stress. In fact, what we eat in a day, when we eat it, if we exercise, the intensity of the exercise, if we’re rundown or our immune system is taxed, and other daily factors can profoundly influence the following intermittent fast.
Longer fasts, like a 24 hour fast, 48 hour fast or even a 5-day water fast can produce even more profound benefits. Around day 4 without food, the body actually begins producing its own stem cells!
Like I mentioned above, for intermittent fasting and to begin getting comfortable with this autophagy promoting lifestyle tool, I recommend starting with a simple 12 hour fast and then working up to a 16 or 18 hour fast. The most important piece of this is to listen to your body. Fasting shouldn’t be extremely uncomfortable or painful; it should be fairly easy or with only some minor discomforts. If your body is telling you that you are fasting too much, you probably are. Listen to the cues and follow what is best for you. I promise, there are benefits to even a 12 or 14 hour overnight fast if that’s what feels best to you!
When it comes to my “autophagy diet,” there are specific foods that I include in the context of an overall whole foods diet. Both the Glow15 diet and a keto diet (especially High Fiber Keto) promote autophagy, so I always use that as the base of what I eat during my eating windows.
The premise of this is that eating low carbohydrates, as in the keto diet, helps to keep insulin levels low which helps to promote autophagy during the day, even when eating!
My Glow15 program isn’t necessarily a low carbohydrate plan, although the Glow15 principles can be applied to a keto diet. With Glow15, when higher carb whole foods are included, we do so with the evening meal. This allows autophagy to dial up during the overnight fast and continue throughout the day with high-fat and low-carb eating. Finally, with dinner, the carbs will dial down the autophagy, but the rhythm of autophagy continues each day. I like to think of this as “pulsing” my autophagy!
No matter your diet, you can still benefit from including certain plant foods that give the autophagy process a boost.
This list makes my mouth water! Isn’t it amazing that tea, chocolate, blueberries, and wine can be a part of a health-promoting diet?
I hope that this discussion will help you feel empowered with the science of autophagy and has shown you how intermittent fasting can truly be a profound tool to incorporate into your days and weeks. Without changing anything else, simply by beginning an intermittent fasting practice, many people notice changes in how they look and feel. With autophagy, you are promoting wellness at the cellular level, so it isn’t surprising that intermittent fasting can profoundly benefit all systems of the body and support you in reaching your biggest health goals!