Firstly, what is intermittent fasting (IF)? It is a lifestyle of eating which originated thousands of years ago. It entails going without food for an extended period of time (famine) and then breaking the fast with a large meal (Feast). However, there are several ways in which intermittent fasting can be implemented. We will focus on why IF overall is life-changing.
Many myths arise when we talk about healthy eating habits. One of the more prominent myths people live by is we required to eat six small meals a day. The rationale behind this is we keep our body in a metabolic advantageous state. The body is assumed to be in a state of metabolism and breaking down of food. If you do not eat frequently, your body enters starvation mode and will retain any food it consumes, not allowing the body to burn fat stores. However not much research has been done on this topic, which is surprising given that most people accept it as the gospel truth. The truth is cereal companies were a huge driving force behind this idea with the goal to promote their products. Research has shown your body will only enter starvation mode after 3-4 days of fasting.
Studies have shown the health benefits of fasting is numerous and profound.
These include normalization of insulin sensitivity, boosting, mitochondrial energy increase, increase Human Growth Hormone (HGH), lower inflammation, lower triglycerides, shed unwanted fat, eliminate cravings, reduce oxidative stress, increase BDNF and increase longevity and lower blood pressure. We will be focusing on weight loss, HGH, brain functioning and insulin sensitivity.
Fat is not the first energy source the body utilizes. Glycogen which is (stored glucose in muscle and liver and blood sugar will be used first and then after depleted fat is utilized. While glycogen stores still remain in the system, the body would not be able get to the fat stores, hence no weight loss. It takes 6-8 hours for glycogen to be metabolized completely. Only then will the fat stores be accessed and utilized for energy expenditure.
HGH is also regarded as the fitness and anti-aging hormone. The main function is to heal, grow and repair tissues within the body. It also is responsible for muscle growth and increased levels of energy. Young children have large amounts of HGH thus providing them with the ability to grow rapidly, and also having high levels of energy. Fat loss is another benefit HGH yields. This occurs as HGH increases the breakdown of fat stores to utilize for energy. Insulin and HGH is indirectly proportionate. As HGH increases, insulin action decreases and vice versa. According to the American College of Cardiology, intermittent fasting causes an 1300% increase in woman and 2000% in men. IF also showed to increase longevity and cancer survival rates.
The brain’s preferred source of fuel is ketones which are released as a result of the burning of fat. Ketones increase memory, concentration, which has a protective effect of Alzheimer’s and dementia. One of the markers which signifies brain health and is Brain-Derived Neurotrophic Factor (BDNF). It provides us with protein which promotes healing, repair and growth of new neurons. This increases our neuroplasticity, allowing us to form new pathway and retain our formally made pathways. BDNF is increased by 400% as a result of IF. It also improve neural muscular junction-nerve connected to muscle. Meaning communication between our nerves and muscles are enhanced.
Insulin sensitivity is important as it determines how efficient your body utilizes insulin. Insulin transfers glycogen to the cells which is then used for energy. Lack of insulin or insulin not been sensitive to glycogen causes a build-up and glycogen which causes all the metabolic chronic diseases we have today. IF improves insulin sensitivity, preventing the accumulation of glycogen. Sleep medicine clinic showed that eating 6 meals a day is less beneficial for diabetes patients. Allowing yourself to fast for certain period of time is advisable.
IF enhances cardiovascular and brain functions and improve several risk factors for coronary artery disease and stroke including a reduction in blood pressure and increased insulin sensitivity. This occurs as a result of chronic inflammation and cholesterol been reduced and controlled. The heart and brain becomes more resilient to stress thus heart attack and stroke is reduced. Interestingly, these benefits to the heart and brain are similar to those of regular physical exercise, suggesting shared mechanisms.
References
1. CMAJ March 20, 2013 (Canadian medical association Journal)
2. American college of cardiology in New Orleans 2011, annual scientific session
3. International journal of obesity 2011;37:714-27
4. Washington post December 31, 2012
5. Free radical Bio Med 2007;42:665-74
6. Cell Metabolism December 2, 2014: 20(6); 9911005
7. British Journal of Nutrition 2013 October 110(8):153447
8. Proceedings of the National Academy of sciences November 25, 2014; 111(47); 1664716653
9.British Journal of Diabetes and Vascular Disease March/April 2013: 13(2); 6872
10. Reutrakul, KL Knutson– Sleep medicine clinics, 2015 – sleep.theclinics.com