Fasting means not eating for a certain period of time. Fasts can last anywhere from several hours to days at a time, and there are different reasons a person might fast. Let’s look at some benefits of fasting, different ways to fast, and whether it’s advisable for most people.
Fasting is Nothing New
Although fasting has become more popular in recent years, humans have been doing it for many, many years. Religions like Christianity, Buddhism and Hinduism have employed fasting since ancient times for spiritual and self-healing reasons. Today, many people also turn to fasting for weight loss results and other health benefits.
What are the Biggest Benefits of Fasting?
There is some solid evidence on the health benefits of fasting. Research has shown that some types of fasting may be beneficial for blood pressure, cholesterol, insulin sensitivity, and glucose levels [1,2,3].
Fasting also reduces nighttime eating, which is associated with a higher risk of diabetes and obesity, and may improve metabolism .
Those who use fasting for religious reasons find it helpful for connecting more deeply to a higher power and seeking guidance.
And today, many people use intermittent fasting as a tool for weight loss and detoxification.
Types of Intermittent Fasting
Intermittent fasting means only eating within a certain window of time and abstaining from food outside of that window. Instead of fasting for days or longer, which can become dangerous without professional supervision, intermittent fasting is safer and more doable.
There are three main types of intermittent fasting:
- 16:8 fasting: Eating with an 8-hour window and fasting outside of that window (for 16 hours). For example, only eating between the hours of 12-8pm.
- Alternate-day fasting: Fasting every other day. Some people will not eat at all during the “fasting” days while others will simply eat fewer calories during those days.
- 5:2 fasting: Restricting calories to 20-25% of normal intake two days of the week while eating normally the other five days.
Each of these has its uses, but 16:8 fasting is the most common—and easiest for most people to maintain.
Should You Try Fasting?
Fasting for shorter periods of time is likely fine, even good, for healthy adults. In humans, studies have shown intermittent fasting to be very effective and safer than long-term fasting.
However, it’s the same level of effectiveness as any diet—and the key is whether or not you can stick with it over a long period of time.
If you have health problems or take medications, it’s best to consult with your doctor before trying any form of fasting. Fasting is also not advised for those with a history of disordered eating, kids, or women who are breastfeeding or pregnant.
All this being said, your body does still need regular fuel and nutrition from whole foods. Outside of your fasting window, focus on organic fruits and vegetables, whole grains, beans, legumes, lean proteins, and healthy fats when you do eat. Avoid refined grains and sugars as much as you can, and be sure to get enough fiber.
Quality still matters—in fact, it’s extra important if you want to get the most benefits of fasting.