TY - JOUR
T1 - Long-term dietary protein intake and subjective cognitive decline in US men and women
AU - Yeh, Tian Shin
AU - Yuan, Changzheng
AU - Ascherio, Alberto
AU - Rosner, Bernard A.
AU - Blacker, Deborah
AU - Willett, Walter C.
N1 - Publisher Copyright:
© The Author(s) 2021. Published by Oxford University Press on behalf of the American Society for Nutrition.
PY - 2022/1/11
Y1 - 2022/1/11
N2 - BACKGROUND: Diet is one of the modifiable risk factors for cognitive decline. However, studies on dietary protein intake and cognitive decline have remained limited and inconclusive. OBJECTIVES: In this study, we aimed to investigate the associations between long-term dietary protein intake and subsequent subjective cognitive decline (SCD). METHODS: We included 49,493 women from the Nurses' Health Study (NHS) (1984-2006) and 27,842 men from the Health Professionals Follow-up Study (HPFS) (1986-2002). For the NHS, average dietary intake was calculated from 7 repeated semi-quantitative FFQs (SFFQs), and SCD was assessed in 2012 and 2014. For the HPFS, average dietary intake was calculated from 5 repeated SFFQs, and SCD was assessed in 2008 and 2012. Poisson regression was used to examine the associations between dietary protein, amino acids, and various protein food sources with subsequent SCD. RESULTS: Higher protein intake compared with total carbohydrates was associated with lower odds of SCD. When substituting 5% energy from protein for the equivalent percentage of energy from total carbohydrates, the pooled multivariable-adjusted ORs (95% CIs) were 0.89 (0.85, 0.94) for total protein, 0.89 (0.84, 0.94) for animal protein, and 0.74 (0.62, 0.88) for plant protein. When substituting 5% of energy from animal protein with plant protein, the OR was 0.84 (95% CI: 0.72, 0.97). For protein food sources, higher intakes of beans/legumes, fish, and lean poultry were significantly associated with lower odds of SCD, but higher intake of hotdogs was associated with higher odds of SCD. CONCLUSIONS: Higher protein intake was associated with lower odds of SCD when compared isocalorically with carbohydrate. Plant protein sources were also associated with lower odds when compared with animal protein sources. Our findings suggest that adequate protein intake, and choices of protein sources could play a role in the maintenance of cognition and should be studied further.
AB - BACKGROUND: Diet is one of the modifiable risk factors for cognitive decline. However, studies on dietary protein intake and cognitive decline have remained limited and inconclusive. OBJECTIVES: In this study, we aimed to investigate the associations between long-term dietary protein intake and subsequent subjective cognitive decline (SCD). METHODS: We included 49,493 women from the Nurses' Health Study (NHS) (1984-2006) and 27,842 men from the Health Professionals Follow-up Study (HPFS) (1986-2002). For the NHS, average dietary intake was calculated from 7 repeated semi-quantitative FFQs (SFFQs), and SCD was assessed in 2012 and 2014. For the HPFS, average dietary intake was calculated from 5 repeated SFFQs, and SCD was assessed in 2008 and 2012. Poisson regression was used to examine the associations between dietary protein, amino acids, and various protein food sources with subsequent SCD. RESULTS: Higher protein intake compared with total carbohydrates was associated with lower odds of SCD. When substituting 5% energy from protein for the equivalent percentage of energy from total carbohydrates, the pooled multivariable-adjusted ORs (95% CIs) were 0.89 (0.85, 0.94) for total protein, 0.89 (0.84, 0.94) for animal protein, and 0.74 (0.62, 0.88) for plant protein. When substituting 5% of energy from animal protein with plant protein, the OR was 0.84 (95% CI: 0.72, 0.97). For protein food sources, higher intakes of beans/legumes, fish, and lean poultry were significantly associated with lower odds of SCD, but higher intake of hotdogs was associated with higher odds of SCD. CONCLUSIONS: Higher protein intake was associated with lower odds of SCD when compared isocalorically with carbohydrate. Plant protein sources were also associated with lower odds when compared with animal protein sources. Our findings suggest that adequate protein intake, and choices of protein sources could play a role in the maintenance of cognition and should be studied further.
KW - amino acid
KW - cognitive function
KW - cohort study
KW - dietary protein
KW - plant protein
KW - protein food
KW - subjective cognitive decline
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U2 - 10.1093/ajcn/nqab236
DO - 10.1093/ajcn/nqab236
M3 - Article
C2 - 34293099
AN - SCOPUS:85118671435
SN - 0002-9165
VL - 115
SP - 199
EP - 210
JO - The American journal of clinical nutrition
JF - The American journal of clinical nutrition
IS - 1
ER -