Fasting, intermittent fasting

Hearing (12:04)

Research in recent decades has further highlighted the mechanism of fasting, or so-called AUTOPHAGY.

This Greek word means self-digestion, which is when our cells break down cellular components that are no longer functioning properly and reuse them or produce energy from them.

The major breakthrough in the physiological background of the cell renewal process was brought about by the research on autophagy by Japanese cell biologist Ohsumi Yoshinori, who received the Nobel Prize in Physiology or Medicine in 2016.

Over time, some components of the cell – mainly proteins – become tired and worn out, and are thus unable to perform their normal functions.

Autophagy is a self-destructive process of cells, during which unnecessary and damaged cell components are degraded by an enzymatic mechanism. This releases energy and materials that can be used to build new cells.

This is related to fasting in that the production of certain hormones – e.g. glucagon released during fasting – and the combined effect of other hormones can stimulate the process of autophagy, thus promoting cell renewal.

If the concentration of glucose in the blood becomes too low (below 3.9–4.0 mmol/L), the pancreas secretes a hormone called glucagon, which triggers the liver to break down stored glycogen into glucose. This glucose is then released into the blood, raising the blood sugar level back up.

Starvation also stimulates the production of growth hormone, and together the two result in cell renewal.

Simply put, it's like taking your car to a repair shop where they replace a few parts to renew the entire vehicle.

This is a very finely regulated mechanism of the body, when the body gets rid of pathogens (viruses, fungi, bacteria), defective cell parts, and worn-out proteins, cell membranes, cell components, and cell organelles that no longer fulfill their function within the cell.

So this is a process that supports cell renewal , which plays a major role in maintaining normal cell metabolism, preventing diseases, and delaying aging.

During the process, the breakdown of the used parts occurs in liposomes (cell organelles) specialized for the breakdown of proteins with the help of various enzymes.

The broken down parts are then transported to the liver, where they are reused or used for energy production.

This allows misfolded proteins to be converted into normal proteins.

The illustration shows the fusion of a liposome (top left corner) and an autophagosome during the process of autophagy:

Autophagy is a natural cleaning and regeneration mechanism of cells that contributes to the body's ability to heal itself, especially as we age. This ancient biological process supports healthy cell renewal and internal cleanliness.

The process can start even during a 14-16 hour fast , if we do not take in nutrients, but only replace fluids.

However, eating (increased glucose and insulin levels) stops it. So juice fasting or calorie restriction diets won't help!

Intermittent fasting has also been shown to reduce fasting glucose and insulin levels, as well as lower cholesterol and blood pressure .

Autophagy doesn't just happen in the liver, but also in fat, BRAIN, and MUSCLE!

Autophagy also plays an important role in maintaining brain health and reducing the risk of neurodegenerative diseases.

Through autophagy, brain cells are able to remove damaged cell components and proteins, which contributes to the protection of neurons and cell regeneration.

Research shows that dysregulation of autophagy – the process being out of control – is associated with the development of brain diseases such as Alzheimer's disease and Parkinson's disease.

Properly functioning autophagy plays an important role in the health of the nervous system and the maintenance of COGNITIVE FUNCTIONS.

Cognitive functions are the brain's abilities to process information, learn, remember, make decisions, solve problems, and communicate. These functions include many areas:

• Memory: storing and recalling information from the past.
• Attention: maintaining and directing attention to information.
• Perception: the perception and interpretation of the external world using the senses .
• Language: understanding and expressing speech, writing and reading.
• Thinking: processing, interpreting and recognizing connections between information.
• Comprehension: interpreting information, recognizing relationships between different concepts .
• Decision making: evaluating and choosing alternatives.
• Problem solving: understanding a given problem and developing an effective solution to it.

These cognitive functions are complex and work together to enable people to think effectively, learn, and conduct daily life.

Cognitive functions can change with age and as a result of various diseases or injuries.

Fasting increases the levels of Brain-Derived Growth Factor in the body.

AENF protects nerve cells by making them more resistant to various types of damage.

AENF also strengthens synapses (the structure between nerve cells through which information is transmitted) and stimulates the formation of new nerve cells and new synapses.

By cleaning our brain cells, we can improve our memory and reduce the risk of developing neurological diseases such as Alzheimer's or Parkinson's disease.

This quality control process is especially important for brain cells.

If autophagy works well, it protects nerve cells and slows the progression of the aforementioned neurodegenerative diseases.

And vice versa; if autophagy does not work or does not work properly, then the person becomes sick.

Even though we don't get protein during fasting, the concentration of amino acids in our blood and tissues remains more or less unchanged because the amino acids degraded during autophagy are released into the intracellular fluid and recycled there: new proteins are produced from them, which are either incorporated or reused as an energy source.

Autophagy in muscles

The role and effect of autophagy in muscle tissues is particularly important, as muscles function using large amounts of energy and are often exposed to various stressors, such as exercise or injury.

Some important effects summarized:

• Muscle regeneration and injury recovery.

Autophagy allows the removal of damaged or damaged muscle cells, thereby promoting muscle regeneration and injury healing.

• Maintaining muscle mass and strength:

Autophagy plays a role in maintaining muscle mass and strength by helping to keep protein and energy reserves in muscle cells at optimal levels.

• Regulation of protein synthesis (formation of proteins from amino acids):

Autophagy regulates protein synthesis in muscle tissues, which is important for cellular metabolism and energy supply.

• Reducing oxidative stress:

Autophagy helps reduce oxidative stress in muscle tissue, which can cause significant damage to muscles, especially during intense exercise or injury.

Autophagy therefore plays a key role in maintaining and improving the health and performance of muscle tissues.

Supporting its proper functioning is important for athletic performance, muscle building, and overall health.

A study in mice also found that fasting mice avoided the loss of muscle mass that occurs with normal aging.

However, EXCESSIVE activation of autophagy over a long period of time can also negatively affect muscle tissue:

It can also lead to loss or damage to muscle mass.

When our body and all of our cells are under chronic stress, it creates changes that can negatively affect autophagy. Therefore, we need to live in a way that keeps our cells 'happy'.

The capacity of autophagy declines with age. In old age, the level of molecular damage becomes predominant, and the cells' ability to clean and self-clean becomes impaired.

Autophagy is actually a central regulatory system of the aging process.

Almost all of the 500 genes known today that increase lifespan exert their effect through the autophagy system!

It is also essential for cell growth and the process of tissue regeneration.

The latter is quite illustrative.

The zebrafish used in the experiments are able to regrow their tail fin if it is cut off (amputated).

It has been proven at ELTE that by turning off autophagy genes, fish tails do not grow back and are unable to regenerate.

Why is this significant?

By influencing autophagic systems, cell regeneration can be accelerated , and this may be significant in wound healing or even in the treatment of infarction.

Summary

Flattening the glucose and thus insulin curve, intermittent fasting, exercise, and stress reduction are effective tools for preventing aging and cancer.

Finally, here's a funny cartoon about what would happen if our brains decided on a 'beautiful day' that everyone would fast for 36 hours: