16/03/2026
Many people genuinely believe they are eating far fewer calories than they actually are. It’s not usually dishonesty, it’s simply how difficult it is for humans to estimate food intake accurately.
Research has shown that people can underestimate their calorie intake by a surprisingly large margin. In one well known study, participants believed they were eating around 1028 calories per day, but their actual intake was estimated to be closer to 2081 calories. Their metabolism was normal. The gap came from inaccurate reporting rather than a “broken metabolism”.
In everyday life this often happens because the small things slip through the net. A handful of nuts, a biscuit with coffee, tasting food while cooking, extra oil in the pan, a latte, alcohol poured more generously than expected, or finishing food left on someone else’s plate. None of these feel like a proper meal, but they all contain calories and can add up quickly.
Portion sizes are also much easier to misjudge than people realise, and food eaten while distracted is surprisingly easy to forget later in the day.
Understanding this can actually be reassuring. If weight loss feels slower than expected, it doesn’t automatically mean your metabolism is broken. Often there is simply a gap between what we think we are eating and what we are actually consuming.
For full details and a more in depth look at this topic, visit my blog at:
https://www.simongpt.co.uk/why-people-underreport-calories/
Why do people underreport how much they eat? Research shows many people underestimate calorie intake by a large margin. Here’s why.