Fasting is an ancient practice that has stood the test of time and shows no signs of slowing down in popularity. While there are numerous reasons to fast, weight loss is at the top of the list for many who incorporate this practice into their lifestyle. The global obesity management and weight loss market has a predicted compound growth rate of 8.6% over the next several years, exceeding $377.3 billion by 2026.
There is a push for better, more manageable, economical, and persistent ways to be healthy, and fasting checks all the boxes. Keep reading to learn more about fasting, its benefits, its side effects, its rise in popularity, and the types of fasting you can do.
What is Fasting?
Fasting can be found in many world religions like Buddhism, Hinduism, Christianity, etc., as far back as 1500 BCE. However, therapeutic fasting has existed since at least the 5th century BCE. Greek physician Hippocrates recommended it to patients exhibiting certain symptoms of illness. In fact, Ancient Greece is accredited as the birthplace of fasting.
Fasting is abstaining from food and drink for a specific period. Abstinence from food or drink can be partial or complete. The criteria are determined by the individual doing the fast, including the timeframe.
Aside from religious practice, there are various health reasons for fasting. The primary purpose previously mentioned is weight loss, but fasting has also been shown to improve blood pressure, cholesterol, insulin sensitivity, glucose levels, and more. It is just as much a practice for the mind as for the body since you'll likely experience some unpleasant side effects when you first begin.
Side Effects of Fasting
With any fasting, when done safely, there are more benefits than drawbacks. Side effects are temporary and a sign that the body is simply adjusting to a new practice. Most side effects typically cease within the first month of intermittent or regular fasting, but listening to your body is still important. Check with your physician before regularly fasting to ensure your body is up to the task.
Some common side effects associated with regular fasting include:
- Brain Fog
These side effects can be challenging for some, so it's important to ease into the practice and find what works for you. Making fasting a regular part of your lifestyle, referred to as intermittent fasting, may require you to try different types of intermittent fasting and see which one suits your needs.
Rapid Growth of Intermittent Fasting
More than losing weight, there has been a push for overall health, stepping away from fad diets and harmful products and turning toward a more holistic approach. Millennials spend twice as much on self-care activities as Baby Boomers, including habits, services, and products that help with overall well-being.
As of 2020, in the United States alone, 43% of the population attested to following a specific diet or eating pattern— 5% over the previous year. The most popular eating pattern is intermittent fasting. From 2013 to 2021, search interest for intermittent fasting saw a 162% growth rate, with the biggest spikes happening every holiday season.
It's not just casual interest; mobile apps like ZERO, which offer fasting timers and tips, have logged over 2 billion fasted hours from its users. Data shows an increase in searches for apps like ZERO, fasting teas, intermittent fasting kits, and more in the last ten years. More importantly, it's effective, with 87% of people who've tried intermittent fasting saying it helped them lose weight.
3 Types of Intermittent Fasting
Time-restricted Feeding (TRF)
Time-restricted feeding (TRF) restricts eating to a specific time window, typically between 3 and 12 hours daily. That window means you are fasting between 12 to 21 hours a day. During your TRF window, you can eat as much or as often as you want. Those looking for sustained weight loss typically go for a shorter window. Many health benefits, like weight loss and improved blood sugar levels, have been associated with this type of fasting.
Circadian fasting is a subcategory of TRF in which you align your feeding window with your body's internal clock. This type of fast involves timing your meals with sunrise and sunset, typically reserving your larger meals for earlier and refraining from food in the evenings, which has been shown to improve sleep. One trial where obese participants were placed on a calorie-restricted diet showed those who took in more calories in the mornings and afternoons and less in the evenings experienced greater weight loss and higher reductions in blood pressure than their counterparts.
Alternate Day Fasting (ADF)
Alternate day fasting (ADF) is not for the faint of heart as it involves eating only every other day. You'll have a normal day of eating, no restrictions, then abstain from eating any calories the next day. While it might be a bit more challenging to stick to, evidence shows ADF decreases LDL cholesterol by 25% and triglycerides by 30% over an 8 to 12-week period.
Non-dietary Forms of Fasting
Food-related fasting does have many benefits to your mental health, including stabilizing cortisol, reducing stress levels and increasing dopamine, combating anxiety and depression. It's also been known to increase mental clarity and brain function by increasing brain-derived neurotrophic factor (BDNF) levels. Even so, there are non-dietary forms of fasting you may not have heard of with their own physical and mental health benefits.
Dopamine is a neurotransmitter that sends messages between nerve cells whose main function is to control movement but is also responsible for the brain's reward system. It reinforces certain behaviors with a reward, called the feel-good chemical. This fast involves restricting yourself from excitement to reset your ability to focus.
Screen or social media fasts are similar to dopamine fasts, restricting you from exciting but often anxiety-inducing stimulation. You can restrict yourself from social media like Instagram, Twitter, and Tik Tok or restrict all media forms. Often this is easiest to do when screens like your phone, tablet, computer, and television are restricted.
Product fasts are mostly related to avoiding skincare, cosmetics, and other beauty products for a specific period, like days or weeks. A product fast allows your skin and hair to breathe and return to their natural balance.
Fasting, both dietary and non-dietary, has many benefits to your physical and mental health. Those benefits become lasting when incorporated into your everyday life as intermittent fasting. As the desire for healthier living increases, so will fasting as a lifestyle.