Researchers divided mice into four diet groups and split them into different feeding schedules.
The authors discovered that when the mice fasted for at least 12 hours and kept their eating within a set 12 hour time frame, they lost more weight compared to mice eating the same diet with freedom to eat all day long.
In addition to weight loss, mice in the time-restricted groups also saw improvements in blood sugar, insulin, insulin sensitivity, and hunger hormones compared to groups of mice who ate when they wanted all day.
While it was still ideal to stick to a 12-hour feeding schedule every day of the week, the researchers also discovered that most of the healthy changes could be maintained if the mice stuck to the 12 hour time-frame just five out of seven days a week - independent of diet type (high-fat, high-fructose, eat whatever they want, etc).
The researchers also found that when the mice still ate the same amount of calories as if they had eaten all day, they still reported healthier weight and metabolic markers.
Yes, science now suggests you can “cheat” on the weekends and still see weight-loss, less sugar cravings, improved gut health, better athletic performance, better cognitive performance and more by focusing on just when you eat.
Time-restricted feeding is a subset of intermittent fasting - which has a wealth of research behind it for weight management, blood sugar control, hunger regulation, cancer prevention, inflammation, and more.
Intermittent fasting generally means restricting solid food intake for 24-72 hours at a time, with longer periods sometimes requiring medical supervision. Time-restricted feeding narrows those time windows to a more daily practice.
Fasting through daily windows of 12 hours or more can restrict calories - and calorie restriction has been consistently demonstrated to be the number one way to extend lifespan.
Fasting acts as a “metabolic reset” for your body systems - giving time for your body to clear out inflammation, scavenge for cancer cells, get rid of damaged cells, promote healthy gut microbes, and also allow you to fully digest the previous day’s food.
Food is enjoyment; and, most see strict fasting as an unfair trade-off. Most think: Why decrease quality of life for a few extra years? So while the science is strong for stricter calorie restriction and traditional fasting; its widespread practice can be impractical.
Fewer than 10% of Americans fast for 12 or more hours in any given day (and 70% or more of all American adults are overweight or obese).
While most Americans eat for 15+ hours a day (leaving just 9 hours for fasting and sleep), time-restricted feeding within 12 hour windows (12 hours eating, 12 hours fasting) can give you many of the benefits of stricter fasting, while still giving you the option to eat all day 1-2 times per week.
Of course you can really improve results by improving the quality of the foods you eat, reducing intake of allergic/sensitive, high-sugar/-carbohydrate/-fructose, and processed foods.
Time-restricted feeding is still a surprisingly easy framework to start building your personal diet strategy.