Long-Term Protein Intake May Help Protect Against Cognitive Decline
And plant protein could be the better choice.
This study investigates the relationship between long-term dietary protein intake and subjective cognitive decline (SCD), a self-perceived decline in cognitive abilities that can precede dementia. The research focuses on two large cohorts: the Nurses’ Health Study (NHS) and the Health Professionals Follow-up Study (HPFS).
PMID: 34293099
Key Points
Aim
To explore whether higher dietary protein intake and specific protein sources (animal vs. plant) are associated with reduced odds of SCD over decades of follow-up.
Methods
Participants: 49,493 women (NHS) and 27,842 men (HPFS).
Dietary Assessments: Repeated food frequency questionnaires (FFQs) spanning over 20 years.
Outcome Measurement: SCD was assessed via questionnaires in 2012 and 2014 for NHS and in 2008 and 2012 for HPFS.
Analysis: Poisson regression was used to evaluate the association between protein intake and SCD, adjusting for factors like age, BMI, physical activity, smoking, alcohol use, and medical history.
Results
Higher Protein Intake vs. Carbohydrates:
Substituting 5% of energy from carbohydrates with protein reduced the odds of SCD:
Total protein: Odds ratio (OR) = 0.89.
Animal protein: OR = 0.89.
Plant protein: OR = 0.74 (strongest effect).
Plant vs. Animal Protein:
Substituting 5% of energy from animal protein with plant protein further reduced the odds of SCD (OR = 0.84).
Protein Sources:
Beneficial: Beans/legumes, fish, lean poultry.
Detrimental: Processed meats like hotdogs were linked to higher odds of SCD.
Related
Practical Takeaways
Plant-based proteins (beans, legumes) should be prioritised over animal proteins for long-term cognitive health.
Incorporate lean animal proteins like fish and poultry while avoiding processed meats.
Aim to replace some carbohydrate calories with protein to support physical performance and cognitive health.
Key Takeaways
Higher overall protein intake is associated with lower odds of subjective cognitive decline compared to carbohydrates.
Plant proteins provide stronger protective effects than animal proteins.
Choosing high-quality protein sources is crucial for maintaining cognitive health as part of a balanced diet.
This study highlights the importance of dietary choices not just for physical fitness but also for long-term brain health.
Reference
Yeh TS, Yuan C, Ascherio A, Rosner BA, Blacker D, Willett WC. Long-term dietary protein intake and subjective cognitive decline in US men and women. Am J Clin Nutr. 2022 Jan 11;115(1):199-210. doi: 10.1093/ajcn/nqab236. PMID: 34293099; PMCID: PMC8755047.