If you have ever gone down the health and fitness rabbit hole, you’ve probably heard of intermittent fasting. It’s frequently touted as a solution for weight loss, heart health, physical performance and even mental clarity. But ask seven different intermittent fasting enthusiasts what their eating schedule is like, and you’ll have seven different answers. So what exactly is intermittent fasting, and what does Ayurveda say about it?
The following are the most common types of intermittent fasting. Note that sometimes “fasting” means “not eating,” and sometimes it means to restrict calories, eat only a little, etc. There’s a lot of variation.
The 5:2 Diet: Eat normally five days of the week, and severely restrict calories to about ¼ of your dietary needs the other two days.
The Warrior Diet: Fast for 20 hours every day, and then eat large amounts of protein-rich foods during the four hours before bed.
Alternate-Day Fasting: A 24-hour fast (complete or just restricted calories) every other day.
Eat-Stop-Eat: Another name for doing one to two 24-hour fasts within the course of a week.
Time-Restricted Eating: Stop eating after dinner, and then wait 12-16 hours to eat again, every day.
You may notice that the first four of these operate on a weekly schedule (you might fast every Tuesday and Thursday, for example), and the last one operates on a daily schedule. This is an important distinction, which I’ll get to in a moment.
The Ayurvedic View of Scheduled Eating
Ayurveda loves schedules. Of the three doshas (Vata, Pitta, and Kapha), Vata is the one that is most likely to go out of whack and cause problems, and eating meals at the same time every day is deeply soothing to Vata. It’s not an exaggeration to say that everyone benefits from eating regular meals. Not only does eating regularly pacify Vata, but it also aids digestion (so that your body knows what to expect, and when, and can prepare to digest well), sleep (having a regular light dinner in the early evening gives your body time to digest before you get in bed, so sleep is deeper and more efficient), and elimination (having a good-quality bowel movement in the morning is a priority).
Time-Restricted Eating: New Branding, Time-Tested Concept
Of the above forms of intermittent fasting, then, the only one that is compatible with an Ayurvedic way of eating is the last one: time-restricted eating. Eat a light dinner around 6pm, avoid snacking after dinner, go to sleep by 10pm having digested your meal already, wake around sunrise, have a small breakfast around 8 after your yoga practice, have your biggest meal around noon when your digestive fire is strongest. Lather, rinse, repeat. No meals need be skipped, no complicated schedule needs to be planned. We are biologically predisposed to follow our circadian rhythm and do things like sleeping, waking, and eating at predictable times.
Time-restricted eating plans are sometimes broken down into 12:12 (12-hour fast, 12-hour eating window), 14:10 (14 hour fast, 10-hour eating window), or 16:8 (16-hour fast, 8-hour eating window). Kapha types can go the longest without food. It may be appropriate for Kaphas to skip breakfast if they are not hungry and eat their first meal at 11am or so, resulting in a roughly 16 hour fast if they finish dinner by 7pm. Vata and Pitta types should generally not go that long without eating, and could instead benefit from a 12 or 14 hour fast each night, eating three regular meals throughout the day.
So if time-restricted eating is the type of intermittent fasting that you do, congratulations! You’ve made a choice that is great for your digestive fire and sustainable in the long term.
The Other Four Kinds of Intermittent Fasting
The process of digestion starts not when we taste the food, but when we start anticipating the food, feeling hungry, thinking about the taste, smelling or seeing the food as we cook. If we are eating when we’re not hungry, we’re missing a crucial first step in digestion; and if we eat on an unpredictable schedule, we are less likely to feel hungry for our meals. These schedules that involve fasting on a Tuesday, eating on a Wednesday, and so on, are ignoring a crucial fact: your body does not know it’s Tuesday. Your body DOES know it’s noon. We have a daily internal rhythm, not a weekly one. So YOU may know that “On Wednesdays we eat at 2pm,” but your digestive system is confused and doesn’t know whether or not it will be fed today at all.
In the short term, it is indeed possible that these long, irregular periods of fasting can result in some weight loss. In the long term, it will dampen the digestive fire further and weight gain will inevitably creep up, if one is predisposed to it. Much better to get your digestive fire on-line than to try to “trick” your body into losing weight.
10 Words to Live By
Ultimately, what it comes down to is that simplicity and sustainability are a much healthier (and more enjoyable) way to eat. Remember Michael Pollan and his advice to “eat food, not too much, mostly plants?” Perhaps if you want to tweak that advice Ayurvedically you could say, “Eat regular meals. Mostly at lunch. Don’t snack at night.”
