The Science of Fasting
Autophagy is self healing, self reconstruction and our own body knows exactly when to switch it on. The most common and effective initiator of autophagy is fasting or the absence of food. In most cases this process takes about 24-36 hours of food abstinence before kicking-in.
Here is how it works. Just like our body houses organs like our heart and lungs, our cells house organelles such as mitochondria and the nucleus. After ~36 hours of fasting (just water) our biochemistry starts an amazing process of tuning-up, recycling, fixing, reconstructing, replacing, cleaning and throwing into the fire, all the damaged and unnecessary materials which are present inside every cell of our body and slowing us down. In addition, autophagy cleans your cells from toxins, dead bacteria, heavy metals and overall pollution inside the cell. Think about it. If we are made up of organs which are made up of cells, then fixing damage and clearing accumulated debris and toxins from cells equals fixing our organs which equals fixing our whole body. The idea and the science were felt to be so important that in 2016, Yoshinori Ohsumi was awarded the Nobel Prize in Physiology or Medicine for his contributions in this field!
Autophagy is awesome!! It is a perfect example of the efficiency and coordination of our biochemistry and metabolism which in turn moves us closer to balance and homeostasis. It is an example of the wisdom and survival knowledge embedded in our DNA as a result of millions of years of human evolution. Autophagy directs the body to save what it can by recycling it and burn everything else to be used as energy. If you think about it, it's the same thing that we humans do in times of war, cold and scarcity. We re-purpose, reuse and recycle provisions, discarding anything that is holding us back. Fasting and autophagy will help to turn your body into a fine tuned machine and bring you one step closer to becoming biologically fit!
I want to highlight the 4 essential gains derived from autophagy/fasting.
1. Mitochondrial biogenesis : The formation of new mitochondria.
2. Microbiome restoration: For example, most bacteria that proliferate in a sugar heavy diet will die during fasting.
3. Replenishment of essential micronutrients: Our fat cells are full not only of fat but also of unused essential micronutrients as well as accumulated toxins that will be released, used or cleared during fasting.
4. Gives our immune system a much needed opportunity to rest and recover: Eating and digesting food utilizes more than half of our daily expended energy. Eating is also the main activator of our immune system as everything we eat is foreign to our body. As you can see, not eating gives our body and immune system a big rest and that saved energy can be redirected to other important healing processes in the body.
As you will learn here with us at Boston healthiest, most human diseases begin with damage to our mitochondria, microbiome, immune system and essential micronutrients (the Fantastic 4). On the other hand you can be absolutely sure that if the fantastic 4 are healthy, you are healthy. Optimal health is the result of an efficient balance between supply and demand of the energy stored in foods resulting in a beautiful homeostasis between cell damage and repair. That is why what we eat, when we eat and what we do has such impact on our health and happiness.
Fasting is the voluntary abstinence from food. Fasting is an ancient tradition vital to humans’ physical and spiritual health. Fasting is now also widely appreciated by science for its beneficial effects on human metabolism, happiness and health span. Growing scientific evidence from different parts of the world suggests that in the full absence of calories from proteins, carbs and fats, our genius body flips a "metabolic switch”. Basically our body starts the process of liberating the energy supply stored as fat in and around our organs and in our belly. This process is done via fatty acid oxidation and ketone production while at the same time prioritizing the safeguarding of lean muscle mass and preserving full body and brain function.
Overeating, inactivity and environment are 3 major causes of unwanted fat build up. Expanding neck and waist lines are clear signs of developing metabolic syndrome and metabolic syndrome is at the beginning of most chronic diseases seen today. Metabolic syndrome is associated with hypertension, diabetes, fatty liver, high cholesterol, and heart disease. What is less well appreciated is its connection to cancer, Alzheimer's disease, autoimmune diseases, among others. Extra fat around our organs is associated with aging faster. Fasting provides a mechanism that not only improves overall body composition but also triggers the activation of biochemical processes and signaling pathways that optimize human performance and physiological function, slowing the processes of aging and disease. as you can see, fasting is a biological necessity.
Fasting is a scary concept for a lot of folks. Not to worry! Start with small habit changes, every one of which will bring you closer to biological fitness. Start by extending the "fasts" between your meals. Avoid the temptation to snack. This will be easier to do if you don't keep processed foods in the house. This can be your first habit change. Develop new shopping habits (see habits). You can then move to shrinking your window of eating. If you start eating at 7 AM and have your last bite at 9 or 10 PM, try delaying breakfast until 8 AM and and stop caloric intake by 7 PM. Now your overnight fast will be increased from 9 hours to 13 hours. Some people call this "intermittent fasting". With only this single change in schedule and no change in food intake, you will see weight loss and improved metabolism. Do the math. This single lifestyle change, this adjustment in eating schedule, will translate into your have fasted a whopping 60 days by the end of 1 year. This has HUGE metabolic benefits and I know you can do it! Eventually, as your metabolism improves, you will find it becomes easier to extend your periods of not eating. In a few weeks you will find that you are now seriously considering your 1st 24 hour fast! But remember, please consult your doctor.
Starting up our machinery.
It is important to be aware that every time you eat, you are starting up the machinery. What does this even mean? Eating spikes our blood sugar and then our insulin, among other hormones. When our insulin levels are up, we are in fat-storing mode. It is that simple. Remember that the insulin stays up an average of 5-6 hours after eating, longer after eating foods containing added sugars. But here's the catch, blood sugar comes down after only 2-3 hours. So, at this point, you will experience hunger and be tempted to eat again. The problem here is that this snack will more likely get stored as fat because the insulin is still up from the original high glycemic meal AND not only that, now insulin will be up for ANOTHER 5-6 hours! The cycle begins again. Why does this matter? Because this cycle results in insulin resistance/metabolic syndrome which is where most chronic diseases start. If you stick with low glycemic foods, high in fiber and micronutrients, your body will be much better prepared to shift to an alternative energy source like glycogen or fat because your insulin spike will be much lower and slower. Low insulin means less fat accumulation.
Dispelling the myths about fasting:
1. I will loose important muscle mass. Our body is well adapted with mechanisms to move between energy sources. If our blood sugar is dropping and we need fuel, we have glycogen stores in place as our back-up. After this is depleted, our body will transition to fat breakdown. Only a trivial amount of muscle may break down in these transitions but they will be recouped with our next meal.
2. My metabolism will slow down. We have known since the 1940's that caloric restriction results in metabolic slowing but fasting leads to a metabolic boost. (please connect link to the study). One can theorize that when we are low in calories we will need that energy (provided through the process autophagy) to get our food. Nature's perfect solution.
3. I'll starve! Fasting is the VOLUNTARY avoidance of food. Most folks have at minimum a few pounds of stored fat in which case, we will not starve with 1 or even a few days of not eating. Humans store every excess calorie as either glycogen or fat. This is a biologic safeguarding for times when no food is available. If we don't eat today, we can just serve up yesterday's leftovers :)
4. It's unsafe. If you are under age 60 and are not on any medications for existing conditions, you should be able to safely fast. Fasting has been a human practice practice for thousands of years and many cultures continue to practice fasting or intermittent fasting today. Please always consult your doctor about this first.