For decades, the premise of diets have revolved around what you eat. 

Atkins dieters believe that carbs are the devil, keto dieters are all about that high-fat lifestyle, while Paleo dieters won’t eat grains that didn’t exist pre-agricultural revolution. Today, that focus has shifted to not what we eat, but when we eat.

Everything that happens in our daily life revolves around the time of the day, and as much as we’d like to think that we have total control over our meals, a lot of what we eat and when we eat has been scheduled around work, appointments, and everything in between.

This pattern of eating means that people often find themselves eating at odd hours and often too close to bedtime, leaving their brains confused and their bodies struggling to keep up.

(Image credit: Sanah Suvarna/Unsplash)

Like sleeping, how we process food is also deeply reliant on the body’s circadian rhythm. Essentially an internal daily timetable, the cycle responds primarily to light and darkness, with sleeping at night and being awake during the day being the most common example. 

Chronically disrupted circadian rhythms not only affect sleep, but also prevent the body systems from working efficiently, leading to insulin resistance, fat storage, and increased risk of disease over time, which explains why the most widely touted preventative medicine today is at least eight hours of good sleep every night.

The concept

Chances are your eating pattern now lasts over 15 hours a day and well past dark, which clashes with the body’s release of melatonin and lowered insulin resistance as it prepares for sleep.

Like intermittent fasting, the circadian rhythm diet advocates time-restricted eating of your daily calories within an eight to 10 hour block when the sun is up, leaving a 14-hour fast between your last meal of the day and the first meal of the next day. 

(Image credit: Joseph Gonzalez/Unsplash)

For this diet, experts have suggested swapping your dinner for breakfast. Instead of bagels or processed cereal, eggs and avocado with toast or a portion of salmon with pasta will help keep you more satisfied and less hangry thoughout the day, especially after the long overnight fast.

Lunch should be less heavy but with a good proportion of protein, fat, and healthy carbohydrates, while dinner should be the smallest meal of the day, especially as your body’s insulin sensitivity decreases before bed. Ideally, you should consume bout 75 percent of your nutrition before 3pm.

The benefits

No one likes being hungry and that’s why diets like these are hard to stick with. The team kindly suggested I gave this diet a go earlier this week and so quite begrudgingly, I sacrificed my happiness for the sake of an honest report and lasted all but two days. If you’re someone who’s used to small meals and lives for snacking in between, this diet will be a difficult one to get used to.

(Image credit: Travis Yewell/Unsplash)

The reported benefits, however, make it worth it. When the body is depleted of sugar, it taps into the body’s reserves, such as the carbohydrates that get stored in the liver. Fasting overnight allows the body to convert fat to ketone bodies, which fuel the brain and heart. Besides, your body isn’t struggling to digest your leftover pizza binge while also trying to repair itself. You’ll also be more inclined to skip dessert after dinner, which is truly a habit we could all get behind.

(Image credit: Jenny Hill/Unsplash)

Interestingly, the circadian rhythm works for exercising too; working out outside in the early morning can be a big mood booster, especially since that’s when your cortisol levels begin to rise before peaking. To fight the midday slum, a quick visit to the gym brings oxygen back into the body after hours spent hunched over the desk while rushing deadlines. An evening sweat session, on the hand, is associated with lower stress levels, better endurance and improved anaerobic performance, like sprinting and resistance training.

Unlike many diets, the circadian rhythm diet isn’t about skipping meals or cutting calories. It’s about listening to what your body needs and not what your mind wants, and not eating during the time when you don’t need fuel can make a whole lot of difference to how your body takes on the day, whether the sun is up or not.

Shatricia Nair
Deputy Editor
Shatricia Nair is a motoring, watches, and wellness writer who is perpetually knee-deep in the world of V8s, tourbillons, and the latest fitness trends. She is fuelled by peanut butter and three cups of coffee a day.