Fasting: Types of Fasting

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You have likely fasted at some point, whether intentionally or unintentionally. The unintentional times probably occurred when you got so preoccupied with work or other activities that you didn’t have the time to eat. While asleep, you’re essentially in a fasted state, unless you regularly sneak into the fridge for a snack or two at 2 AM.

An Unforgettable Fast

In my first semester in college, I took an introductory programming class in Java, my first-ever experience with coding. On several occasions, I had gotten away with starting my programming assignments late yet managing to submit them before their deadlines. This had fostered overconfidence and deluded me into believing that I could always delay work but still clutch it out on deadline day.

One assignment finally stumped me. The warning signs were there, but I had ignored them. Everyone was complaining about it, and Piazza, our Q&A discussion board, was more active than usual. Naturally, I started it late, unaware of what was in store.

A couple of hours in, the assignment’s inherent complexity hit me. Fixing one bug would surface another. My code editor screamed with errors. Piazza posts proved useless. At 3 AM on deadline day, I knew my streak was about to come to an end. Out of options, I resorted to office hours as a last-ditch effort.

Office hours were packed, so it was difficult to get enough help. My fellow procrastinators had gathered in the teaching assistants’ computer lab, leading to long wait times. The persistent errors I was encountering caused me to spend the entire day in the lab, skipping all my other classes and meals.

Long story short, I ended up submitting a half-working solution just before midnight, consoling myself with a popular tenet from the procrastinator’s handbook:

There’s more to life than this

I hadn’t eaten anything all day, so I was starving. I devoured a 14-inch protein pizza (‘Yes’ to all the protein options), a bag of chips, and several Mountain Dews. It still baffles me how I consumed all that in a single sitting but I suppose hunger, fueled by stress and frustration can morph into something quite monstrous.

I woke up the next morning feeling awful, of course, promising myself that I would never be dragged back into the trenches of procrastination. You may relate if you’ve ever pulled an all-nighter and binged on junk food after finishing a major assignment.

Anyway, those who fast intentionally do so in different ways. Some fast for religious reasons, which I covered previously. When it comes to health, there are two main approaches:

• Intermittent fasting — Cycling between periods of fasting and eating, like 16/8 or 5:2 plans.
• Prolonged fasting — Fasting continuously for multiple days or weeks, only consuming water, black coffee, or broth.

Intermittent Fasting

Intermittent fasting involves alternating periods of fasting and eating. Its focus is on when to eat as opposed to what to eat. Nevertheless, when coupled with a nutritious diet and healthy eating habits, one can optimize its complete benefits.

In the health realm, intermittent fasting is the most popular and well-researched approach. The most recognized mode of intermittent fasting follows an x/y regimen — fasting for x hours with a y-hour eating window per 24 hours.

The 16/8 method, fasting for 16 hours with an 8-hour eating window, is the most common. Many studies have uncovered the health benefits of the 16/8 method, and it is most recommended by nutritionists and health experts. Other methods such as 17/7, 18/6, 19/5, 20/4, and OMAD (One Meal a Day) follow a similar template.

During the fasting window, most people take fluids that have 0 or minimal calories. These include water, tea (sugarless), black coffee, broth, or apple cider vinegar.

The 5:2 diet is an intermittent fasting protocol that involves eating normally for five days of the week and drastically restricting calorie intake for the remaining two days. It was popularized by Dr Michael Mosley in his bestselling book, the FastDiet.

Unlike a true fast which involves eating nothing for a set amount of time, the goal of this fasting protocol is to limit calorie consumption to about 25% of a person’s regular intake. For example, if you normally consume 2000 calories, then on fasting days you would consume about 500 calories.

It is essential to monitor these hours to track when you start or end your fast. Various applications can assist with this, and personally, I rely on Zero to track my fasting hours plus receive valuable tips during the process.

Prolonged fasting

Prolonged fasting involves fasting for multiple days or weeks continuously while only consuming non-caloric beverages such as tea, black coffee, water, and sometimes bone broth or supplements.

Prolonged fasting is not recommended for people who are on medication or have medical conditions like eating disorders, malnourishment, or underweight. Most prolonged fasts last 2–3 days. Anything longer should be medically supervised due to health risks.

According to the Guinness Book of Records, Angus Barbieri holds the record for the longest fast without solid food, which lasted 382 days (from June 1965 to July 1966).

During this period, he only consumed tea, coffee, soda water, and vitamins while under medical supervision. Weighing 456 pounds (207 kg) initially, he lost a remarkable 276 pounds (125 kg) by the end. Incredibly, he maintained the weight loss even 5 years later.

In a more recent case, famous endurance artist David Blaine fasted for 44 days (September 5 and October 19, 2003) taking only water. He was put in a transparent plexiglass box that was suspended mid-air from a crane above the banks of the River Thames in London.

After the fast, he lost 54 pounds (24.5 kg). He had to be hospitalized afterward, however, as he suffered symptoms of refeeding syndrome. This medical condition happens when food is reintroduced too quickly after a starvation period. The rapid nutrition shift causes electrolyte imbalances that could lead to heart, respiratory, or kidney failure.

Breaking a Fast

When you break a fast, it’s recommended you do so slowly with easy-to-digest foods. For an intermittent fast, some of the options for your “breakfast” could include:

• Lean Proteins: chicken, turkey, fish, eggs, legumes.
• Healthy Fats: avocado, nuts, seeds, olive oil.
• Cooked vegetables and Leafy Greens: Broccoli, bell peppers, spinach, kale.
• Fruits: Preferably low-glycemic options like berries.
• Fermented Food: Sauerkraut, kimchi, greek yogurt.
• Bone broth and soups.
• Vegetable juices.

When breaking a longer fast, you want to stick to smaller portions and food options way easier to digest. Incorporating Apple Cider Vinegar (ACV) is useful in aiding the digestion of your post-fast meal. Potential meals include:

• Bone broths and soups.
• Steamed vegetables.

While individual experiences may differ, it is advisable to steer clear of fried or greasy foods, beef, raw vegetables, and carbohydrate-rich options (including refined carbohydrates and sugary beverages) when concluding longer fasting periods. Check out this informative breakdown from Dr Jason Fung:

Closing Thoughts

There are different fasting regimens that people follow based on their health, goals, and preferences. Whatever type they choose to follow, fasting offers health benefits such as weight loss and easier weight maintenance, reduced inflammation, and improved heart health.

We’ll be taking a deeper dive into how your body reacts in a fasted state as well as the benefits and potential complications associated with fasting. Stay tuned.