Is body weight affected by when you eat? Here’s what science knows so far
Changes to our circadian rhythm can impact our physical and mental health. Olga Miltsova/ Shutterstock

Most diet and health advice is broadly based on the assumption that a calorie is a calorie (and it doesn’t matter when they’re consumed). But some research suggests that our bodies actually use calories more efficiently when consumed in the morning as opposed to the evening. This points to a strategy that could be beneficial for weight loss.

While there are many reasons for this phenomenon, one may be our circadian rhythm. This is the natural, internal process that regulates our sleep-wake cycle over a 24-hour period. Not only does our circadian rhythm make us feel tired at night and alert during the day, it also regulates the timing of the body’s processes – including digestion, metabolism, and appetite regulation – by secreting certain hormones based on what and when we eat, our physical activity and time of day.