In what ways do you deceive yourself about what or how much you eat?
The Short Answer
Underestimating is common. In the study behind the claim, ten people with a history of diet resistance underreported what they ate by 47% (plus or minus 16), measured by indirect calorimetry and body composition; the doubly-labeled-water method and the 19% often quoted for controls are not in its published abstract.[1] The deception isn’t conscious lying; it’s largely unconscious: selective memory, forgotten incidental eating, and portion distortion. The bites while cooking don’t count. The handful was small. The healthy label means unlimited. The drink was “just water” (with juice). Until you honestly inventory these blind spots, you’re working with corrupted data.
Something to Sit With
You’re not lying to yourself on purpose. But somewhere, there’s a gap between what you think you’re eating and what you’re actually eating.
Where’s the gap? What are you not seeing?
Learn More
The research on underreporting. The finding is consistent across methods:
Calorie underestimation. Self-reports come up short, by 47% on average among ten people with a history of diet resistance. The 19% often quoted for controls is not in the paper’s published abstract.[1]
Portion distortion. The error runs both ways: large portions get underestimated and small ones overestimated. Beverages were off by 30-46% and pasta by 44%, while high-energy-density snacks were overestimated.[1]
Selective memory. People remember main meals better than snacks.[1] The incidental eating (the tastes, the bites, the extras) gets lost.
This isn’t about honesty. Even people trying their best to report accurately underreport. The mechanisms are largely unconscious.[1]
Common blind spots. Where does the untracked eating hide?
Bites while cooking. A taste of the sauce, a sample of the stir-fry, a piece of cheese while prepping. These add up but don’t register as “eating.”
Drinks. The coffee with cream. The smoothie. The juice with breakfast. Liquid calories often fly under the radar because they don’t feel like food.
The handful. Nuts from the jar. Chips while passing through the kitchen. A few candies from the bowl. “Just a few” adds calories that don’t feel countable.
Restaurant portions. When you “ate a salad,” you’re thinking of the lettuce. You’re not counting the dressing, croutons, cheese, and fried protein that can turn it into a far bigger meal than the word suggests.
“Healthy” foods. A health label moves the estimate: shown identical nutrition labels, people rated cookies called organic as lower in calories than the same cookies labeled conventional.[2] Granola, smoothie bowls, trail mix: calorie-dense, and the label makes them feel like they don’t count.
The extras. The bread before the meal. The sauce on the side. The butter on the vegetables. These don’t feel like “eating” because they’re accompaniments.
Why we deceive ourselves. Why is not established, and the underreporting research finds it largely unconscious; these are common explanations, offered as possibilities:
Protecting self-image. If you think of yourself as eating healthily, acknowledging the untracked eating threatens that identity.
Avoiding cognitive dissonance. If you’re trying to eat less but actually eating more, recognizing the truth is uncomfortable.
Confirmation bias. You remember the salads. You forget the cookies. Memory can serve the narrative you want to believe.
Wishful thinking. If you don’t track it, maybe it doesn’t count.
Finding the truth. To identify your blind spots:
Track everything for a week. Not to restrict, to observe. Write down every bite, including the tastes, the handfuls, the drinks. Use a scale for portions. The goal is data, not judgment.
Pay attention to the “not counting” moments. When do you think “this doesn’t count” or “this is so small it doesn’t matter”? Those are the moments to scrutinize.
Ask an observer. If you live with someone, ask them what eating they see that you might not track. Outside perspective catches what internal attention misses.
Notice the gap. If you’re eating “perfectly” but not seeing results, this is usually where it is: diet resistance is typically explained by intake underestimation rather than by metabolic abnormality.[1]
Further reading:
- Lichtman SW et al., “Discrepancy between self-reported and actual caloric intake and exercise in obese subjects”[3] — New England Journal of Medicine, 1992
- Guyenet SJ, The Hungry Brain[4] (2017) — The psychology of food consumption
Written by AI, directed and approved by me. How this is made →