Regular fasting has been practiced for generations and many people are now realizing that there are many health benefits associated with this ancient practice. A few of these benefits include weight loss (due to the increased use of body fat for fuel), prevention and/or treatment of pre-diabetes and Type 2 diabetes (due to reduced insulin secretion), enhanced thinking, mood, and metabolism (due to increased norepinephrine and growth hormone secretion), cellular repair and regrowth, and reduced hunger (due to suppression of leptin and ghrelin). Fasting also has anti-aging and brain health benefits, including a reduced risk for Alzheimer’s disease and cancer!
What exactly IS fasting and more importantly is it safe? Fasting is CHOOSING to abstain from food (not eat) for a set period of time. It is very different from starvation. In starvation there is no choice and the period of time is unknown. During fasting there is a specific time period during which people CHOOSE to give their bodies a break from eating. This allows them to undergo housekeeping and help keep their cells, tissues, and organs working at their best. Specific biochemical changes take place and these changes safely and effectively help them improve our health.
People may wonder, “What are the different types of fasting? How long should I avoid eating?” Time-restricted feeding occurs when people limit their food intake to a specific eating “window” each day. For example, if a person eat all of their food between 8:00 am and 8:00 pm they leave 12 hours during which they do not eat. This is a 12-hour daily fast. If they eat only between 10:00 am and 8:00 pm they practice a 14-hour daily fast. This type of fasting can be practiced daily. Alternate day eating occurs when they eat every other day. On the day they fast they do not eat. The following day they resume their normal eating pattern. This may be done once per week. Total fasting occurs when a person does not eat for several days. This type of fasting is much more extensive and may be practiced once per year.
So who should fast? Most people can safely fast and receive tremendous benefits. There are a few exceptions, however. A person who is malnourished or underweight, less than 18 years of age, pregnant, or breastfeeding should not fast. If a person has gout, is taking medications, has Type 1 or Type 2 diabetes, has gastroesophageal disease, or a history of disordered eating (anorexia nervosa, bulimia nervosa, or binge eating disorder) they should consult their healthcare provider before fasting. During fasting it is important to drink plenty of fluid. The following beverages may be consumed during fasting: water, black coffee, green/black tea (no sugar or sugar substitutes), and chicken/beef/vegetable broth (avoid bone broth due to protein content). Medications and vitamin supplements can also be taken as long as they don’t cause nausea. At times it may necessary to move fasting periods around medication times. A person can talk with their healthcare provider if they have any concerns regarding fasting and medications.
If someone is struggling with food cravings or food addiction fasting is an effective way to help break the cycle of unhealthy eating. In addition, fasting saves time and money (less time buying and preparing food). Fasting also helps when a person is traveling or they find themselves in circumstances with limited healthy food options. Whether it’s weight loss, health improvement, or prevention of disease fasting can help a person meet their goals and find optimal well-being for life!
Reference: The Obesity Code by Dr. Jason Fung (2016)