The Study
Caloric restriction, resting metabolic rate and cognitive performance in Non-obese adults: A post-hoc analysis from CALERIE study.
This study watched people who ate less food for two years and saw that their brains seemed to work a little better — but only if their bodies burned energy differently. It doesn't prove eating less made their brains better, just that those two things happened together.
Analysis score
Maximum 90 for a randomized controlled trial.
Where the score came from
When people ate 25% fewer calories for two years, their brains performed better—but only if their resting metabolism (how many calories they burn while sitting still) went up.
Where does this study sit?
Reviews of RCTs (Meta-analyses)
Max 100Randomized Trials
Max 90Reviews of Cohort Studies
Max 85Cohort Studies
Max 72Reviews of Case-Control Studies
Max 63Case-Control Studies
Max 58Cross-Sectional & Case Series
Max 50Expert Opinion
Max 565 / 100
Quality score
Participants are randomly assigned to treatment or control groups, minimizing bias. The gold standard for testing whether an intervention causes an effect.
Key takeaways
Summary
Based on the study abstract and findings.
- 1Yes—this suggests that even without losing weight, your brain may function better if your body becomes more metabolically efficient.
- 2People who ate less and had higher resting metabolism saw better thinking test scores; changes in weight, activity, or total calories burned didn't matter.
Score breakdown, methodology, conflicts of interest, evidence analysis & raw study data
Publication
Journal
Journal of psychiatric research
Year
2020
Authors
R. Grigolon, E. Brietzke, A. Trevizol, R. McIntyre, R. Mansur
Related Content
Claims (6)
When two people consume the same net calorie deficit, their resting metabolic rates and hormone levels may differ depending on how much total energy they are expending through activity and metabolism.
In healthy adults who reduce their calorie intake over a long period, changes in the rate at which the body uses energy at rest are linked to changes in cognitive performance, even when total calorie burn and physical activity levels are accounted for.
In people who are not overweight, eating fewer calories does not lead to better thinking skills by changing how much energy they use in a day or how active they are, because those changes are not linked to thinking ability once their resting metabolism is taken into account.
When people eat fewer calories, their cognitive performance may change due to shifts in resting metabolic rate, not because of changes in their weight or body fat. The key factor appears to be how the body regulates energy use at rest.
In healthy adults between 21 and 50 years old, reducing calorie intake by 25% for two years is linked to modest improvements in memory and metabolic rate, even when body weight and total energy consumption do not change, which may indicate that changes in how the body uses energy influence cognitive function.
In adults who are not obese, a higher resting metabolic rate is linked to better cognitive performance at rest, even when accounting for body size and how much energy they consume.
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.