What is Reverse Fasting?

A little known intermittent fast for people who don’t like to miss out on breakfast and want to keep their circadian rhythm in check

6 min readJan 20, 2021

Constant munching around the clock has been attributed to a variety of health issues, such as heart disease, diabetes and obesity due to the disruption to our circadian rhythm and metabolism. Intermittent fasting has gained popularity in recent years, with an increasing trend in people choosing to skip breakfast and have their first meal later in the day. Normally, people who intermittent fast will just have lunch, a late dinner and then fast for at least 12 hours (up to 16 hours) until lunchtime the next day whilst only consuming water or calorie-free liquids. However, this eating regime may not be suitable for people who don’t like to skip breakfast, particularly early birds. If your someone who rises at 5 am and goes to sleep before 9 pm then this eating regime may just not be sustainable in the long run as you will be forced to tolerate over 7 hours before your first meal. This only becomes more challenging if you have any training sessions in the early morning and need a post workout recovery meal afterwards.

Following a shift in working hours recently, I now just do not have the time for dinner as I work from the early afternoon to the later evening, and so I was forced to change my meal times to earlier on in the day. I typically currently have my breakfast around 8 am, a couple of hours of waking up after sunrise (usually around 5:30 am), and then lunch before 2 pm. I may have a snack between this two meals, as well as an additional snack before 4 pm to keep my energy levels up, which means that I have an eating window of around 8 hours, so I therefore typically benefit from around 16 hours of fasting (16/10). After changing my eating regime, I decided to make a quick search on Google to see if this sort of dietary plan already exists and I stumbled across reverse fasting.

Reverse fasting is just another type of intermittent fast where you finish your last meal earlier on in the day, to allow for at least 12 hours of fasting. You can of course adjust the eating window to suit your schedule. Surprisingly, despite being relatively unknown to the general public, a considerable amount of research has been carried out on reverse fasting. According to various sources, studies have shown that it is actually more beneficial to not skip breakfast and have an early dinner or late lunch as your last meal instead. There has been a lot of debate in recent years wherever breakfast is the most important meal of the day, and its reputation has been tainted somewhat, but skipping dinner may just help to restore breakfast to the king of all meals.

Reverse fasting attempts to mirror the early bird circadian rhythm embedded in the DNA of a lot of us. If we think about it, it is highly likely the vast number of us are not programmed to eat after sundown. Evolutionary, eating after dark was largely unheard of in the absence of technology and artificial light, from even just before the 20th century. Cavemen would have not eaten after dark unless they were capable of creating a bonfire. Our bodies in the evening are reportedly less-insulin resistive as our bodies are likely to want to work on gene repair, hormonal regeneration and restoring gut health. Eating in the evenings may impair our ability to perform these processes.

A number of studies have shown that skipping dinner tends to have the better effect on insulin level than breakfast, which in turn reduces the chance of disease and improves brain function, as well as reducing weight. If we think about this it is fairly logical, eating during the sunlight waking hours, when our mental and physical demands are the highest, provides us with the fuel and calories to perform at our optimum level. Research has shown that people who skip dinner and instead eat only in the morning and afternoon have better lipid profiles, sugar control, cognitive memory than those who eat late in the day, as well as weighing less on average. In a lot of countries, such as America, a lot of people consume the majority of their calories after dinner, such as whilst snacking on popcorn whilst watching the TV, leading to obesity problems, and the cut-off window provided by reverse fasting will eliminate this problem.

A lot of health experts recommend eating dinner at least two hours before bed to allow time for digestion before you fall asleep. If you intermittent fast or have a late dinner then this will mean that you should go to bed at a late time. Going to bed whilst your body is still digesting may lead you to feel sluggish and tired the next day when you wake up, partly due to the late night spike in insulin levels, but this problem is avoided with the reverse fast. Furthermore, there is a lot of thought that our metabolism peaks at midday, between 10 am and 2 pm, which falls in the schedule of the reverse fast.

There are mixed results from studies concerning the metabolic effects of exercising whilst fasting. Although, exercising on an empty stomach tends to burn more fat, studies show that the majority of people who eat before working out tend to perform better than those who fast. People who exercise on an empty stomach sometimes report feelings of weakness and dizziness. In addition, research from the University of Bath shows that eating breakfast before exercising may help the body to metabolise carbohydrates better during activity and later in the day, thus leading to more calories burnt in total.

It is still early days for my trial with reverse fasting, so I may be experiencing the placebo effect. However, at the very least establishing an early eating window has meant that I do not have any problems for finding a time to eat dinner whilst I am working in the evening, which means I avoid snacking on unhealthy options. I also feel like I have increased mental clarity and energy to focus on my personal tasks at hand with no dinner to plan and not even feeling hungry, before getting an early night to recharge for the next day.

I am currently fasting for over 12 hours every day, so I may be profiting from autophagy to some extent. For the past six months, I have extensively day fasted one day a week, but have taken a break from this whilst I focus on reverse fasting. During my day fast, I often feel lightheaded, dizzy and nauseous, which is often alleviated by drinking some salted water. However, I have not had any of these symptoms whilst reverse fasting. If you feel that 12 hours is too long then you can have something to curb your appetite if needed in the evening before going to bed, such as a piece of ginger, or a teaspoon of honey. In addition, having some honey before sleep has been shown to have a positive influence on burning calories during sleep.

As always, I am by no means saying that reverse fasting is a solution for everyone. It is up to you to try and see if it works for you and your body. There is increasing evidence that our circadian rhythms are determined genetically, so it may not be up to us to decide if we are a night owl or an early bird. If you are a night owl, it may be wise to stick to the traditional intermittent fast in the long term.

If you want to take the reverse fast one step further you can try the Buddha’s Diet or the Warrior Diet. A lot of Buddhist monks typically only eat one meal in the morning and avoid eating after noon, but allow for some sugar, such as some dark chocolate in the evening. I personally, am not too convinced as they often end of drinking a lot of energy drinks, leading to unnecessary weight gain.

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What is Reverse Fasting?

A little known intermittent fast for people who don’t like to miss out on breakfast and want to keep their circadian rhythm in check

Written by Patrick Raizerov