Autophagy fasting is a timed approach to dieting that leverages the process of autophagy. As the wording implies, fasting is intentional food restriction for a designated amount of time. This is also referred to as time restricted eating.
Disclaimer: You should always check with your own provider before beginning a diet regimen to ensure it is safe for you to do so, fasting included.
How Fasting Induces Autophagy
According to newer research, autophagy can actually be induced during prolonged periods of fasting.
The exact mechanism and reason why this happens is still yet to be fully understood, but it may have to do with the body being sent into a starvation-like mode and having to find alternative energy sources that can be accessed by autophagy.
Some animal studies suggest that a fast as short as 18 hours per day can induce autophagy. More human research is still needed to confirm a direct causative relationship.
Related: What is Spermidine?
What is Autophagy?
Autophagy is a homeostatic process through which cells digest and subsequently clear waste products of metabolism. These may include misfolded proteins or other macromolecules that may be damaged or old.
In deconstructing the word autophagy, “auto” means “self” while “phagy” means “eat.” So the word autophagy literally means “self-eating.”
Ongoing research is continually pointing towards the importance of effective autophagy in maintaining health and promoting longevity in humans.
Dysregulation of this process is now thought to be linked to several chronic conditions like cardiovascular disease, insulin resistance, and even the development of cancer or other neurodegenerative diseases.
The Autophagy Process Explained
There are several structures within our cells that mediate the autophagy process.
The first organelle that is involved is called an autophagosome. This structure moves through the intracellular space and consumes macromolecules that need to be destroyed.
The autophagosome then combines with another organelle called a lysosome, which contains enzymes that physically break down the macromolecules that have been collected by the autophagosome. The lysosome then recycles these contents into compounds such as amino acids, sugar, and nucleotides and returns these back to the cell itself for repurposing.
Other Types of Autophagy
There are also more selective types of autophagy:
- Mitophagy is the process of degrading mitochondria
- Reticulophagy is the process of degrading the endoplasmic reticulum
- Xenophagy is the process of degrading foreign microorganisms
- Aggrephagy is the process of degrading aggregated proteins
Benefits of Autophagy
Preliminary animal research and limited human research have shown benefits of healthy autophagy, ranging from decreasing overall inflammation to neurologic protection.
1. Decreased Inflammation
In recent years, more research has begun to tie dysregulated autophagy to several inflammatory illnesses like Crohn’s Disease, lupus or even infectious illnesses like tuberculosis.
2. Decreased Insulin Resistance
Some studies also show a link between dysregulated autophagy and insulin resistance and obesity. These studies also show that fasting tends to improve overall blood sugar control. Healthy autophagy might even play a role in cardiometabolic health and blood pressure control.
3. Cancer Prevention
Efficient autophagy may get ahead of cancerous changes by detecting and eliminating cancerous cells, DNA, or proteins before they have a chance to proliferate into tumors.
4. Neuronal Protection
One study that looked at the nervous system specifically found that fasting induced significant upregulation of autophagy in neuronal cells, which could possibly offset the neurodegeneration that can come from aging.
Types of Fasting Regimens
There are several fasting protocols one can follow.
One type is an every other day fasts that last a full 24 hours each time. There are also fasts that involve fasting on 1-2 consecutive days of the week. These are called the 6:1 and 5:2 diets, respectively.
Some shorter fasts may involve restricting eating on a daily basis to a narrow window of time like a 6 to 8 hour window with a 18 to 16 hour subsequent fast, respectively. Calorie free beverages like water or tea and coffee (without cream or sugar) are able to be consumed during the fasting hours.
Why and When is Autophagy Stopped?
Conversely, in order to stop autophagy, studies in animals have shown that consuming food starts to reverse—or at least slow—this process and return it to basal homeostatic levels.
While more research is needed, the current literature does suggest a positive correlation between fasting and healthy autophagy, which has potential longevity benefits for humans as discussed. A fasting regimen is not for everyone, however.
- Alirezaei et al. 2010. Short-term fasting induces profound neuronal autophagy
- Brandhorst et al. 2015. 00224-7#secsectitle0030" target="_blank" rel="noopener" data-lasso-id="18559">A Periodic Diet that Mimics Fasting Promotes Multi-System Regeneration, Enhanced Cognitive Performance, and Healthspan
- Jamshed et al. 2019. Early Time-Restricted Feeding Improves 24-Hour Glucose Levels and Affects Markers of the Circadian Clock, Aging, and Autophagy in Humans
- Martinez-Lopez et al., 2017. System-wide benefits of intermeal fasting by autophagy
- Qian et al., 2017. Autophagy and inflammation.
- Shang, et al. 2011. Nutrient starvation elicits an acute autophagic response mediated by Ulk1 dephosphorylation and its subsequent dissociation from AMPK
- Yang et al. 2009. An Overview of the Molecular Mechanism of Autophagy
Tana Bao, BSN, MSN, APRN, NP
Tana is a family nurse practitioner dual board board certified through the American Academy of Nurse Practitioners (NP-C) as well as the American Nurses Credentialing Center (FNP-BC).