You're not eating too much, you’re eating too long

Monday, 15 June 2026

Most of us eat across a 15-hour window every day. Reducing that down to 8 or 10 hours triggers intermittent fasting benefits, lowering glucose and insulin while unlocking your body's ability to burn fat and build metabolic flexibility.

Reader Question

“I keep hearing about intermittent fasting. I am 52, a bit stuck around the middle. Would tightening up my eating window to just 8 hours a day actually make a difference or is it nonsense? So many ‘experts’ with conflicting information online, I really don’t know really what to believe”

Chris, 52.

Professor Grant Schofield’s response

Chris, nutrition scams are everywhere. This isn't one. But it's no magic wand either, here's what the evidence actually shows

Convenience food has turned us into grazing machines: 7am breakfast, snack, lunch, another snack, dinner, 9pm chocolate (you deserve a treat), midnight pantry raid.

We think we’re eating three meals a day, but research shows the median eating window is 14 hours 45 minutes. That’s right most of us eat from when we get up until we go to bed. Some of us past that. This is a problem because it keeps our blood sugar and insulin constantly high and therefore fat burning low making us feel lethargic and our energy levels unstable.

Time-restricted eating is a simple idea: pick an eating window of around 8-10 hours and close the kitchen the rest of the time. It gives your metabolism the daily rhythm modern life stole, the same rhythm your ancestors lived by.

A Stanford team tracked real people and found most of us eat across nearly our entire waking day. When they gave adults an 8–10 hour eating window for three months, blood sugar improved and people lost 3–4% of their body weight and trunk fat with no calorie counting. A 2024 review of 20 trials confirmed it: time-restricted eating reliably reduces body fat, total weight, and waist size. Tighter windows work better.

The reason it works is simple. When you stop eating for long enough, insulin drops and your body switches to burning fat. Most of us have lost that ability because we never stop eating long enough to let it happen.

That ability is called metabolic flexibility. Your body smoothly switches between carbs for quick energy and fat the rest of the time. Walking the dog, doing housework, sleeping, you should be running on fat for all of it. Most of us aren't.

Once insulin stops being high all the time, the uncontrolled hunger goes and the hanger disappears. You become able to tap the weeks of stored fat you already own.

And there is one more thing. Structure beats decision fatigue. Most overeating happens at night when we are tired, stressed, or hunting for comfort. A closed kitchen removes the decision entirely.

So where to start, Chris: Shut the kitchen three hours before bed. Push breakfast back an hour. Nail a 14-hour overnight fast first (dinner done by 7pm, breakfast at 9am). Then tighten to a 10-hour window a few days a week. Many people find the sweet spot with just an 8 hour waiting window.

Maybe you’re not stuck because of what you’re eating.

You’re stuck because you’re just eating all day.