Reverse Fasting: Everything You Need to Know
- Written By:Dr. Amy Shah
- Photography:Sarah Elliot
You’ve probably heard about intermittent fasting, you maybe even read about it here. But what about reverse fasting? Probably not. Reverse fasting is a type of intermittent fasting that uses the power of our circadian rhythms. Instead of fasting late into the day, you start by ending your meals early in the day.
This practice is well studied and is often referenced in the medical literature as “time-restricted eating.” It involves restricting your food intake to 8 or 10 hours a day and studies show that it is better to have an early dinner than it is to skip your breakfast.
Traditionally, people who practice intermittent fasting will have a late dinner and then will fast, only consuming water or calorie-less liquids, until 12:00 or 1:00PM the next day. Both styles have their health benefits, but skipping dinner or having an early dinner tends to be more beneficial.
A study on breast cancer survivors that found those who fasted for 13 hours were not only losing weight and but also having a 34% reduction in breast cancer recurrence as opposed to to people who were eating freely. Another study just concluded that if you eat dinner 90 minutes earlier and breakfast 90 min later, you will see weight loss. Eating earlier in the day has shown to improve your insulin levels, reduce your chance of disease, and improve your brain function.
And it makes since evolutionarily. Before all this artificial light, TV, blue light, and cell phones, people were programmed to eat before sundown. If you think back even just 50 or 100 years ago, eating after dark was unheard of. It makes sense that our bodies in the evenings are less insulin sensitive. Our bodies are also more likely to want to work on gene repair, hormones and gut health in the evenings. When you're eating in the evenings, you impair your ability to do all that.
So, how should you start your first reverse fast? Stop eating at 6 PM and then eat your next meal at 6AM or 7 AM. Starting with just 12 to 13 hours is a great way to ease your body into it and you can always adjust it to your schedule. For me, two to three days a week I extend this period to 16 hours between meals.
Whenever you are thinking about trying fasting or any other kind of new diet, you should discuss this with your physician and make sure that it’s right for you!