The Skinny on Fasting

By Brad Matushewski

September 28, 2016


Posted In: Education, Fitness, General Health, London, Nutrition

Fasting is gaining popularity these days…or is it? Fasting has been around a LONG time as part of many religious observances. However, in recent times, intermittent fasting has been picking up steam.

There are many benefits to intermittent fasting. I would like to cover some of these main points here.

1) Fasting can help with weight (fat) loss. Our bodies burn glucose and glycogen (i.e carbohydrate) more readily than fat. Even a lean person has far more energy stored as fat compared to carbohydrate but it takes some time for the chemical pathways to become “upregulated” or turned on. Fasting taps into this by giving our body time to shift towards fat for energy.

2) Fasting improves insulin sensitivity. Insulin is primarily responsible for getting glucose into our cells to use as energy. Diabetes is what results when our bodies can no longer properly regulate our blood sugar. It is apparent that a shortage of insulin can lead to this but it is also possible for our bodies to produce “enough” insulin BUT our cells have a decreased sensitivity to insulin. An analogy is sort of like being hard of hearing – the sound is there; it is just that it is not getting through. Fasting (as well as exercise) can improve this cellular sensitivity to insulin.

3) Speeds up metabolism: There are many people that when they hear “fasting” they say, “WAIT – your metabolism will crash and shut down”. This is not entirely true. In the short term, metabolism actually goes up…not down. Think of this from the time where hunters and gathers were legitimately short of food. It would be counter-productive if our bodies shut down and we lost mental focus – thereby decreasing the chances that we would be successful in acquiring food. Our bodies can go a LONG time with little to no food (have you seen the television program, “Naked and Afraid”) so shorten-term intermittent fasting does not cause our metabolism to shut down.

4) Improves perception of hunger: Real, legitimate hunger can take anywhere from 12-24 hours. Feeling “hungry” 2-3 hours after a proper meal is not true hunger. One of the ways our bodies regulates everything, including hunger is through a balance of various hormones. Poor eating habits can throw off this balance where either you never really are satisfied with a meal and/or you are “think” you are very hungry very soon after. For example, people struggling with obesity do not even receive the signals that indicate satiety with a meal and don’t even necessarily know that they are full. Fasting, again, acts a bit like a reset button. This can lead to feeling full sooner when you are eating.

5) Improves brain function: Studies have shown that fasting can increase something called, “Brain-Derived Neurotrophic Factor” (BDNF) in the brain. BDNF plays a major role in keeping our brains healthy, including protecting the brain against changes associated with Parkinson’s disease and Alzheimer’s.

6) Improves immune function: Many disease processes involve inflammation in some way or at the very least, lead to worsening of the disease either chronically or through acute flair-ups. Fasting has been shown to reduce free radical damage and can even abate cancer cell formation. We often don’t think about our immune system until we are sick, but it is working constantly to keep us healthy. Our bodies have some 37.2 billion cells in them and it just takes one to go rogue before we end up with cancer.  That pretty much happens every day that least one cell in our body goes rogue and if it weren’t for our immune system doing its part, it would turn into cancer.

There are numerous systems and plans for fasting. How do you choose? My recommendation is to seek the advice of an expert in the field and know that not every fasting approach will work for you.  I would however avoid taking advice from “some guy at the gym”. In any approach, do a bit of your own research and ask questions.