Key Takeaway
Low-carbohydrate diet improved verbal memory in older adults with mild cognitive impairment, with improvements correlated to ketone levels
Summary
This study examined whether a very low-carbohydrate diet could improve cognitive function in older adults with mild cognitive impairment (MCI), testing the hypothesis that ketones provide an alternative brain fuel.
Methods
- Randomized controlled trial
- 23 older adults with MCI
- 6-week intervention
- Low-carb (<20g/day) vs high-carb (50%+ calories)
- Cognitive testing before and after
- Urine ketones measured to verify ketosis
Key Results
- Low-carb group showed improved verbal memory
- Memory improvement correlated with ketone levels
- No improvement in high-carb control group
- Trends toward improvement in other cognitive domains
- Weight loss occurred but did not explain cognitive effects
- Effects persisted when controlling for caloric intake
Figures
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Limitations
- Small sample size (n=23)
- Short duration (6 weeks)
- Urine ketones less accurate than blood
- Single-site study
- MCI population may not generalize to healthy adults