Researchers discovered dietary modifications might assist enhance cognitive well being and stave off dementia.
A brand new examine led by investigators from Mass Normal Brigham, Harvard T.H. Chan College of Public Well being, and the Broad Institute of MIT and Harvard suggests {that a} Mediterranean-style food regimen might assist scale back dementia threat. The examine, revealed in Nature Drugs, discovered that folks on the highest genetic threat for Alzheimer’s illness benefited extra from following a Mediterranean-style food regimen, exhibiting a higher discount in dementia threat in comparison with these at decrease genetic threat.
“One purpose we needed to check the Mediterranean food regimen is as a result of it’s the solely dietary sample that has been causally linked to cognitive advantages in a randomized trial,” stated examine first writer Yuxi Liu, PhD, a analysis fellow within the Division of Drugs at Brigham and Ladies’s Hospital, a founding member of the Mass Normal Brigham healthcare system, and a postdoctoral fellow on the Harvard Chan College and Broad. “We needed to see whether or not this profit could be completely different in folks with various genetic backgrounds, and to look at the function of blood metabolites, the small molecules that replicate how the physique processes meals and carries out regular capabilities.”
Over the previous couple of a long time, researchers have discovered extra concerning the genetic and metabolic foundation of Alzheimer’s illness and associated dementias. These are among the many commonest causes of cognitive decline in older adults. Alzheimer’s illness is understood to have a robust genetic part, with heritability estimated at as much as 80%.
One gene specifically, apolipoprotein E (APOE), has emerged because the strongest genetic threat issue for sporadic Alzheimer’s illness — the extra frequent kind develops later in life and isn’t instantly inherited in a predictable sample. Individuals who carry one copy of the APOE4 variant have a 3-to-4-fold increased threat of creating Alzheimer’s. Folks with two copies of the APOE4 variant (referred to as APOE4 homozygous) have a 12-fold increased threat of Alzheimer’s than these with out.
To discover how the Mediterranean food regimen might scale back dementia threat and affect blood metabolites linked to cognitive well being, the workforce analyzed knowledge from 4,215 girls within the Nurses’ Well being Research, following members from 1989 to 2023 (common age 57 at baseline). To validate their findings, the researchers analyzed comparable knowledge from 1,490 males within the Well being Professionals Observe-Up Research, adopted from 1993 to 2023.
Researchers evaluated long-term dietary patterns utilizing meals frequency questionnaires and examined members’ blood samples for a broad vary of metabolites. Genetic knowledge had been used to evaluate every participant’s inherited threat for Alzheimer’s illness. Contributors had been then adopted over time for brand spanking new circumstances of dementia. A subset of 1,037 girls underwent common telephone-based cognitive testing.
They discovered that the folks following a extra Mediterranean-style food regimen had a decrease threat of creating dementia and confirmed slower cognitive decline. The protecting impact of the food regimen was strongest within the high-risk group with two copies of the APOE4 gene variant, suggesting that food regimen might assist offset genetic threat.
“These findings counsel that dietary methods, particularly the Mediterranean food regimen, may assist scale back the chance of cognitive decline and stave off dementia by broadly influencing key metabolic pathways,” Liu stated. “This suggestion applies broadly, however it might be much more vital for people at a better genetic threat, resembling these carrying two copies of the APOE4 genetic variant.”
A examine limitation was that the cohort consisted of well-educated people of European ancestry. Extra analysis is required in various populations.
As well as, though the examine reveals vital associations, genetics and metabolomics usually are not but a part of most scientific threat prediction fashions for Alzheimer’s illness. Folks typically do not know their APOE genetics. Extra work is required to translate these findings into routine medical observe.
“In future analysis, we hope to discover whether or not concentrating on particular metabolites by food regimen or different interventions may present a extra customized method to decreasing dementia threat,” Liu stated.
Authorship: Along with Liu, Mass Normal Brigham authors embrace Chirag M. Vyas, Cheng Peng, Danyue Dong, Yuhan Li, Oana A. Zeleznik, Jae H. Kang, Molin Wang, Frank B. Hu, Olivia I. Okereke, A. Heather Eliassen, Meir J. Stampfer, and Dong D. Wang. Further authors embrace Xiao Gu, Yanping Li, Fenglei Wang, Yu Zhang, Yin Zhang, Walter C. Willett, and Peter Kraft.
Funding: This examine was funded partly by the Nationwide Institutes of Well being (R00DK119412, R01NR019992, R01AG077489, RF1AG083764, U54AG089325, P30DK046200, UM1CA186107, P01CA087969, R01HL034594, R01HL088521, R01HL060712, U01CA167552, R01HL035464).
