Autophagy isn’t a new word, at least not in this blog.

As previously described in some other blog posts, autophagy is a cellular process in which your cells “eat themselves”. (As a reminder, cells are the fundamental working units of your body – they come together to form your tissues and organs, like brain cells in your brain, and conducting cells and muscle cells in your heart.)

It may sound weird, but the word “autophagy” originated in the Greek language and literally means “self-eating”. Of course, this process only happens when necessary. When toxic waste and damaged components including damaged proteins accumulate inside of your cells, autophagy cleans up. This assures lower levels of toxicity inside of cells.

Autophagy is different than apoptosis, a process in which cells kill themselves because they’ve accumulated too much damage. Cells going through autophagy are often saved from this cell suicide process, because they recycle materials and rebuild damaged cellular components.

If autophagy promotes cellular cleanness, do you need it for your body to function normally? The answer is simple – yes, you need it!

So how does it work? Autophagy cleans debris inside cells as a catabolic process.


Catabolism is a form of metabolism that happens when something gets destroyed. Whenever a catastrophe happens, we experience destruction. Whenever catabolism happens, cells “experience” destruction. In this case, autophagy promotes catabolism because it destroys cellular debris. How does this “good” destruction happen? Your cells create structures that envelop damaged cellular compounds and then merge with hungry lysosomes.


Lysosomes are cellular structures that contain specific proteins that are capable of breaking down multiple substances (like how your stomach proteins can digest food). These specific proteins are called enzymes and are responsible for breaking big molecules down into smaller ones. Enzymes are involved in plenty of processes in your body. For example, you have enzymes in your saliva that start to break down an apple as soon as you bite into it. You have enzymes in your stomach that continue to break down big chunks of that apple once you swallow it. And you even have enzymes in your immune cells that help to break down or destroy viruses and bacteria that might have been on the surface of that apple.

Enzymes are extremely powerful machines when it comes to breaking down molecules, and lysosomes have a big range of this “machinery”. You can imagine that lysosomes are fully capable of dismantling cellular trash.

The inside of a cell, where cellular organelles including lysosomes do their work.

Autophagy: Using powerful machinery to clean up

Since autophagy is a process that allows cells in our bodies to break down unnecessary wreckage, it would be ideal if we could control it in our own favor. And indeed, we can!

Fasting (avoiding calories for 12 or more hours) is one of the best ways to promote autophagy in your body. In fact, fasting could be a powerful tool to prevent neurodegenerative diseases such as Alzheimer’s disease – brain cells that experience autophagy destroy and clean up damaged, sticky protein components that can damage cells when they accumulate. For example, autophagy can help clean up sticky protein amyloid plaques* in brain cells – these plaques accumulate in the brain cells of people with Alzheimer’s disease and ultimately damage or kill brain cells.

*Fasting may help to prevent the accumulation of damaged proteins inside of brain cells. But if a person already has a neurodegenerative disease, his or her brain cells may already be stressed enough that fasting could have negative impacts on brain cell survival. So fasting may be better as a preventative measure –  more research is needed.

When you fast, you force your cells to undergo a small amount of stress – similar to the stress that your cells experience during exercise. (Exercise promotes autophagy as well!) After all, there’s a lack of nutrients and calories during fasting, and cells react rather strongly to that! But your cells respond to this stress by boosting their own stress-busting processes. The stressful condition of fasting makes cells change their metabolic responses – or where, how and from what they get their energy. For example, cells start to break down fat for fuel instead of burning primarily sugar.

But this metabolic shift does more than change where, how and from what your cells get their energy. This metabolic shift also improves repairing mechanisms in your cells. It triggers more autophagy! It triggers cells to recycle proteins and compounds, which otherwise could be left drifting and accumulating.

Besides promoting cell “tidiness”, fasting may also delay aging. Celebrities like Jennifer Aniston (actress from “Friends”) and Jack Dorsey (Twitter’s co-founder) are fasting and talking about its anti-aging benefits – many of these benefits may come from autophagy.

What about diseases?

When it comes to brain cells, autophagy can be a powerful tool to prevent neurodegenerative diseases such as Alzheimer’s disease and Parkinson’s. However, when it comes to cancer, recent research shows that autophagy can be tricky.

On one hand, autophagy could be good to stop cancer because it could make damaged pre-cancerous or cancerous cells die. On the other hand, autophagy triggers mechanisms which allow cells to grow healthily by ridding themselves of potentially toxic waste. But cancer cells may overuse autophagy to grow when they shouldn’t, or to grow when they should be undergoing apoptosis.

Should cancer therapies prevent or promote autophagy? If autophagy’s role in cancer seems like a paradox to you, it’s because it really is one. Scientists aren’t yet capable of answering this question fully. However, there’s a common focus on biomarkers.


I promise this is the last scientific term of this blog post! Biomarkers, as the word itself reveals, are biological markers. They are substances that indicate a certain moment of a process. For example, autophagy involves many different steps. Let’s call them autophagy buttons: you can either turn them on and enhance the process; or turn them off and stop it.

However, since autophagy is such a detailed process, scientists have a lot of buttons to explore. Through clinical trials, scientists are working on discovering which biomarkers could be beneficial to press in order to prevent and treat cancer, but this is still work in progress. Cancer doesn’t happen or work the same way in every person and doesn’t happen the same way in every organ. Triggering autophagy in a breast cancer cell isn’t the same as triggering it in a colorectal cancer cell, so this science needs to be explored further in clinical trials.

One young woman exercising yoga on a lake pier in the morning, fog on water surface. People wellbeing relaxation healthy lifestyle concept.

Patience is a virtue

Autophagy has proven to be beneficial to human health. It promotes cell renewal and may delay symptoms of aging. We can promote autophagy in our own bodies through controlled fasting.

But where do we go from here, to further promote autophagy in our bodies? That is still a big question. We have to wait some time until scientists know for sure if targeting this cellular process could be useful in therapies for disease.