Fasting is becoming an accepted health-longevity intervention. Long practiced by many religious disciplines, it fell out of favor in the modern era of abundant high calorie, low nutrition food. Today, there is an explosion of research on the benefits of fasting. Many experts trace this resurgent trend to a popular book published in 1987, The 120 Year Diet Plan, by Dr. Roy Wolford M.D., professor of pathology at the UCLA School of Medicine. His work in biospheres one and two showed the astounding effects of long-term calorie restriction on a multitude of health indicators. This initiated a lot of buzz in the wellness and weight loss industry but soon to fell out of favor due to lack of compliance and complications of long-term calorie deprivation (e.g., poor wound healing and diminished immune function).
With the more recent discovery of nutrient sensing pathways and how they can stimulate the body’s ultimate detox mechanism – autophagy – there is a resurgence of interest in fasting. The methods are numerous, and the nomenclature has become confusing. The following will give you a high-level view of fasting: its benefits, limitations, and proper terminology.
Intermittent Fasting (IF)
IF has joined the popular lexicon and is typically misapplied or misunderstood. It is when you limit food intake intermittently. This term is falling out of favor due to its overuse, improper use, and lack of specificity.
Time-Restricted Eating (TRE)
TRE is eating according to your circadian clock. The work of Sachin Panda at the Salk Institute has demonstrated clear health benefits from restricting food intake to 9-12 hours a day – ideally, have your last meal three hours before bedtime. Some people refer to this as IF; it is actually intermittent eating. This is the natural evolutionary method of eating. A sixteen-hour eating window is unhealthy. Constant access to calorie-rich foods is a new phenomenon in evolutionary history. Eating over a 16-hour period is unnatural, leading to insulin resistance and a host of chronic inflammatory issues. 12-15 hours of fasting daily is recommended. This practice is what most people incorrectly refer to as IF.
Calories Restriction (CR)
CR is the prolonged decrease in caloric intake by 30%. This is pioneering work by Dr. Roy Wolford mentioned in the introduction. CR showed initial promise, but long-term compliance was minimal. People who did stick to it showed poor wound healing, decreased immune function, and chronic stress.
Prolonged Fasting (PF)
PF is when you completely eliminate calories long enough to have created a metabolic shift in your body. The literature is fuzzy, but three days seems to be when these metabolic shifts happen. The first phase is called ketosis. Ketosis is when you switch to using fat for energy rather than just glucose in your diet and the glycogen stored in the body. This is also called beta-oxidation. This must happen on any diet where you are trying to lose weight/fat. Fasting accelerates this process. The initiation of ketosis can vary from 8-48 hours depending on multiple factors.
Phase two is autophagy. When the body is deprived of calories long enough, nutrient sensing pathways will turn on the ultimate digital detox – autophagy (see article below for the five phases of fasting). Water only fasting should be done with extreme caution. Dr. Frank Sabatino, medical director at Balance for Life, has been transforming lives for over forty years. He follows strict pre and post fasting protocols. He has his clients in a controlled environment so they can be closely monitored. He limits their activities to limit complications such as muscle loss and fatigue. Many of his results are nothing short of astounding.
Fasting Mimicking Diet (FMD)
FMD advocates claim that their diet offers significant advantages over water-only prolonged fasting (Dr. Sabatino strongly disagrees). The FMD is typically a five-day program that precisely titrates calories and macronutrients to allow the user to consume limited calories while still getting the benefits of fasting. Water-only fasting has significant benefits, but it must be done in an activity-limited, medically controlled environment. FMD advocates claim the following advantages over water only fasting:
- Improved compliance.
- Healthy fats may encourage greater stem cell generation.
- Although strenuous activity is not advised, you can continue normal daily activities.
- Spares muscle and bone.
- Fasting is the only known physiologic interruption of sleep. One night of short sleep has a dramatic effect on health and safety. With an FMD you attenuate the impact on your normal sleep cycle.
Fasting is slowly becoming widely accepted by the health and wellness community as a powerful intervention with very little downside. This must be tempered with the aforementioned risks. Healthy longevity is a personal journey. It is the goal of Humanity UpgradeTM to be a valuable resource on this most important endeavor.
TRE – Dr. Panda and Dr. Rhonda Patrick offer a comprehensive look at the benefits of TRE and the amazing epigenetics of your circadian clock:
Water only fasting – Dr. Sabatino gives a comprehensive review of the amazing benefits of water only fasting:
Diabetes – Dr. Jason Fung is an endocrinologist in Canada who has had amazing results with fasting in his diabetic patients. He outlines how water only fasting has helped many severely ill patients recover their health and reverse obesity, insulin resistance, type 2 diabetes and other types of metabolic illness. His theories on the pathogenesis of insulin resistance and why most people gain significant weight when they transition to insulin are thought-provoking.
Nutrient sensing pathways and autophagy signaling overview – This article is a great overview of fasting. In a very understandable way, it outlines how dietary restriction affects nutrient sensing pathways and your epigenome. It discusses the five stages of fasting and the importance of refeeding – it is a great, easy to understand, high-level overview.
Summary – There are thousands of articles on fasting. The information above offers a fast and effective way to get up to speed on this amazing healthy longevity intervention.