Autophagy – The good, bad and downright dangerous

There are alot of buzzwords that float around in the diet and fitness world. Most of them are under researched, misunderstood and used to promote ideas that have little to no backing in science. Autophagy is one of the biggest misconceptions being thrown around today. Nobody actually understands it and the methods typically used to try and achieve it are not only unnecessary but can be detrimental.

Lets break it down. What is Autophagy?

Autophagy has several purposes but the primary purpose of it is two fold in functionality.

  1. To provide essential amino acids to the body to enable it to continue proper function in the absence of adequate dietary intake.
  2. To clean up old, defective or just plain inefficient cells and recycle them in the best way possible.

The body is the most elegant machine ever created. The way it manages everything is complex and beautiful. Lets look at how it determines which cells are the best ones to use for autophagy:

Each cell has a series of receptors that accept different signalling proteins. In humans there appears to be 6 or possibly 7 different proteins for this purpose. 

The proteins will come along and attach to a receptor. The protein is like a scanner for the cell. If the cell is in pristine condition then the protein is released. If the cell doesn’t pass the test then the protein stays attached and another comes along and attaches and runs another check. This process continues until all cells are checked and prioritized. 

The body then has a map of what cells can be recycled and what ones are to be left alone. Cells with 7 proteins go first, then 6, then 5 and so on until only cells with no proteins attached are left.

Here is a picture of the process:

So in essence, autophagy is a very necessary and very beneficial process. Now what seems to be pushed is the idea that you have to do something out of the ordinary for this to happen and that we should strive for the very maximum amount of it. This is the problem with the diet industry. If something is good, the maximum possible amount of it must be better. The question I always pose is why would that be the case? We know more is not always better. Too much of anything can be bad. A little bit of tylenol is great for a headache but too much can kill you. So how much autophagy is good and how much is bad?

So the thing that has to be said first is, autophagy happens all the time. Constantly and for various reasons. It happens every night if you don’t eat for more than a few hours or so. How many hours of not eating? Nobody knows for sure. The body constantly needs some amino acids (protein) for various functions and we don’t have any storage for amino acids so after we eat protein it gets used for immediate purposes then any extra gets converted to glucose for storage. I shouldn’t actually say there is no storage for amino acids. There is a very tiny amino acid pool but it is so infinitesimally small that it cannot hold any measurable amount and is only for providing the small number of amino acids that might be needed for a few various metabolic processes. The main point here is that within a short amount of time after eating the body will start looking at the cells that have been marked for autophagy and using them for protein needs. This is how the body manages its resources and keeps things tidy.

Now depending on the persons diet and how often they eat, they may not get enough daily autophagy to be the optimal amount and to clear every cell that may be in need of clearance but if you are only eating 3 meals a day and are eating a ketogenic diet, chances are you are getting an above average amount. That would be good enough to keep the body working well. If you are chronically sick you could benefit from more than the average person. The question now becomes what is necessary to get more and how much more is needed?

Going back to the initial description of Autophagy, the primary reason for it is to provide the necessary amino acids to keep the body functioning normally in the absence of adequate dietary intake. Now the way most “experts” or “gurus” will advise you to get more autophagy is through fasting. Now of course that will do it but why is it necessary to eat nothing at all when all that is required is to limit sources of amino acids? There are no amino acids in fat. There are also no amino acids in carbs for that matter. If you dramatically cut back on protein intake would you not be getting inadequate amounts of amino acids? Why does it require you to not eat anything? Easy answer is that it absolutely does not require fasting. It only requires not eating enough protein.

So what is adequate protein? This will be very different for everyone and it can be very different day to day depending on what you eat. The standard definition of adequate has been determined by the WHO and FAO as 0.45g per Kilogram of lean body weight. That is what has been determined as the amount needed to sustain lean mass of the average person. To give you an example of how little this is, I am 200lbs and my lean mass is 173lbs or 78.5Kg. That equates to only 35.3g of protein to maintain my lean mass. For the average person that will be somewhere more around 20g per day. Now that does not mean that autophagy will not happen if you eat 20g per day. It really depends on how much protein is needed at any given time. If you eat all that 20g at one time then you will be getting autophagy for pretty much the whole day until you eat more protein. If you spread that out over 3 meals you will get less, but that minimum amount of protein takes into consideration that you will be using some amount of autophagy. Since the average health conscious person is likely eating more 3-5 times this amount per day and still gets a relatively adequate amount of autophagy, if they were not they would be riddled with chronic disease and cancer, then we have to assume that if you are eating this bare minimum amount that you would already be getting an above average amount of this amazing process.

There are several ways one can get to this limited amount of protein. You can do a fat fast where you just consume mostly fat all day. This will result in a massive amount of autophagy, if that is what you are really looking for and truly believe that you need more, as you are dramatically limiting protein intake. The upside to this compared to an outright fast is that you will still be eating so the body will not down regulate thyroid hormones and metabolism. Why would you do something to slow metabolism and thyroid hormones when you can get 90% of the result by just limiting protein.

Exercise will use a high level of autophagy. Especially if you don’t eat any protein before the workout. Here is a study talking about exercise induced autophagy:

To be completely honest with you, you can achieve a high level of autophagy by eating only fruit for a period of time. The average person will not be able to consume more than 1200 to 1400 calories of fruit in a day and this will result in getting less than 20g of protein a day. More than adequate to stimulate all the autophagy you would ever need. Some will say that this is going to interfere with weight loss. It isn’t. I wouldn’t call it a great idea to try and live for very long on fruit only but it will absolutely not interfere with weight loss and can actually increase it for most people. With the very small amount of fruit you can eat in a day you will never exceed your bodies ability to store the carbohydrate in muscle and liver glycogen. Once the carbs are stored there, insulin drops back down quickly and you are back to using fat. The interesting part here is, because there is absolutely no fat in fruit, all the fat you will be using that day will come from fat stores. Why is this not a good long term strategy?

  1. We need fat soluble vitamins as well as essential fatty acids. Since there are none of these in fruit, you will go down hill quickly. Not to mention the lack of B12.
  2. With continuously consuming this low level of protein, you will max out your back log of cells that are considered poor enough quality and will start using up valuable lean tissue. Look at people that have been fruitarian long term, yes this is a thing, and you will see that they are malnourished.
Former fruitarian YouTuber

Autophagy also can be maxed out to the level of muscle catabolism simply by not getting enough of the essential amino acids. There are 20 total amino acids used by the human body. 9 are considered essential and all must be present in the daily diet or the body will use autophagy to get them. The other 11 are considered non essential or conditionally essential due to the fact that they can be made from the 9 essential ones. It is still not a great idea to not get any of them because you may not be getting enough of the essentials to fulfill the bodies needs for this plus have enough to create the conditional ones and still end up with deficiency issues. This can be a huge issue with vegans. They often do not get enough of the essential amino acids from plant foods and the body will start increasing autophagy to the point where they are maxed out on poor quality cells to recycle and the body starts using valuable lean tissue.

This is a great example of how people feel amazing at first when they start a vegan diet but after some time they start to feel broken down. Their body uses up all the available crap cells for the amino acids they are not getting and will move onto good cells. The initial autophagy is clearing out some garbage built up over the years but the continued poor amino acid intake of their diet overwhelms the process and they start actually eating the good cells. This is why so many prominent vegan youtubers are coming out saying they quit veganism. Their body just cannot sustain the level of autophagy they are getting and they are breaking down.

The same can be said for people who fast. This is why it is not at all uncommon for people who fast often to develop issues like hair loss and extreme fatigue and trouble maintaining losses. They are maxing out the healthy level of autophagy and are actually catabolizing the good tissues. If you are losing hair, it is a good sign that your body has no more crap cells to use and is starting to sacrifice the creation of hair to try and slow down muscle catabolism. Often times people that have been fasting for long terms find that they gain weight much easier when they do eat. This can be because they have started catabolism of lean mass and this leads to a much slower metabolic rate. Since muscle is the primary user of energy in the body it is a very bad idea to be catabolizing it. Fasting can certainly do this. The end result for those that find they have trouble maintaining weight loss is too fast longer and longer and this only exacerbates the issue. This leads us to the last potential issue with autophagy I am going to talk about.

An extreme version of excess autophagy is anorexia. These people eat so very little that they never get adequate protein. The body must continue to function so it burns through its lean tissue leaving the poor person a walking and talking skeleton. Eventually the body starts catabolizing the organs until finally the diaphragm is completely catabolized and the persons lungs fill with fluid and they die. This is a horrible disease that nobody should ever have to suffer with but this is autophagy to the extreme degree and if we start letting people think that more is better then this can certainly be the end result. It is like an addict chasing a high. I know this is an extreme example but after working with thousands of people I have seen this start to come to fruition. 120lb women coming to me wanting to get leaner and they are already fasting for 2-3 days at a time, or more, and barely eating. This is the next stage. It is frightening.

Enough of the depressing stuff. Let me summarize:

  1. Autophagy is the bodies way of providing adequate amino acids to keep the daily functions in motion in the absence of adequate dietary intake. It also happens every time you have not eaten for a number of hours.
  2. This can be achieved in several ways that do not require not eating at all.
    • Simply restricting protein intake (how much is unknown but less than 1g per KG of ideal weight is likely to provide an above average amount)
    • Fat fast. This will restrict protein enough to promote a massive level of autophagy without restricting total energy and lowering thyroid hormones and metabolic rate.
    • Not really recommended for long term – a fruit only fast can induce a dramatic level of autophagy while also not restricting total energy intake. It can also increase fat loss temporarily but may leave you deficient in various nutrients and essential fatty acids. Use with caution and preferably with the guidance of a professional.
    • Exercise – working out without consuming protein before the workout will induce a high level of autophagy and will also give you all the other benefits of physical activity. Win win.
  3. Fasting is not the best way to achieve this and may leave you depleted, catabolic and losing your precious hair. Not to mention it will lower your thyroid hormones as well your metabolic rate.
  4. Vegans are prime examples of too much autophagy. Inadequate intake of all the essential amino acids will lead to excess autophagy and lead to catabolism of vital lean mass. Most vegans quit as a result of the inevitable breakdown of the body.

I hope this has helped you to better understand Autophagy and some better ways to achieve it. I think there is alot of things the keto community has gotten right but there are still way too many untested and unscientific methods that are being pushed without adequate thought put into the actual processes, mechanisms and potential risks involved. We have come a long way but still have miles to go before we can get humanity back to a place of Common Sense.

Keto ON!

Coach Jack

If you need help getting past a stall, getting your hair to stop falling out or on the other end of the spectrum you need help increasing exercise performance and body composition I have strategies for all of the above. 

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