Location: Jean Mayer Human Nutrition Research Center On Aging
2024 Annual Report
Objectives
Objective 1: Characterize diet to determine patterns that associate with healthy aging, and construct models of the various components of these dietary patterns to determine the contribution that each component of the pattern provides to overall associations, while concurrently considering the joint associations of different dietary components.
Subobjective 1.A: Form a new cohort composed of participants adhering to more plant-based dietary patterns to identify factors associated with long-term adherence to healthier dietary patterns and to examine the health benefits of adherence to these dietary patterns.
Subobjective 1.B: Describe the relationship between water intake, hydration and age, and examine the relationships between water intake and hydration and healthy aging.
Objective 2: Determine the relationships between specific foods, nutrients, and other bioactive dietary components of dietary patterns and healthy aging and key elements of healthy aging, such as physical, metabolic, musculoskeletal, vision, and cognitive function.
Subobjective 2.A: Examine the relationship between inadequate vitamin B12 status and accelerated brain aging and explore potential exacerbation of this relationship by high folate status.
Objective 3: Examine the potential genetic modification of the relationships between dietary patterns and their constituents associated with healthy aging, and employ metabolomic and transcriptomic “signatures” of optimal dietary patterns and of healthy aging to detect pathways that may link diet and healthy aging.
Subobjective 3.A: Examine the association between sugar-sweetened beverage (SSB) consumption and dyslipidemia and determine if single nucleotide polymorphisms (SNPs) in the CHREBP locus affect this association.
Approach
Diet plays a critical role in maintaining health across the lifespan, but questions remain about the relationship between nutrition and healthy aging, including physical, cardiometabolic, and cognitive health. Using an epidemiological approach applied to community-based, aging populations, we will study diet patterns and provide the evidence needed to create interventions to foster healthy aging. Most of our research will focus on the impact of the entire diet and dietary behaviors, a departure from the more traditional approach of isolating single nutrients. This approach, broadly referred to as dietary pattern analysis, is more predictive of health outcomes and more reflective of the way people eat.
We will link this approach with genetics, metabolomics, and transcriptomics in the context of large community-based aging cohorts so we can characterize not just healthy aging phenomena, but make an impact by identifying optimal dietary and behavior patterns at both the individual and population levels. The dietary pattern methodology allows us to capture the complexity of diet and the interactions of different dietary components. In addition to conventional diets, we will include alternative diets such as whole food and plant-based (e.g., vegan diets). We will identify factors associated with adherence to such diets; examine potential mechanisms by which bioactive dietary components affect health outcomes (e.g., B vitamins and dementia); and identify factors, such as genetic variation, responsible for differences in response to dietary patterns and food components (such as sugar intake). Results of this research will allow us to translate the science of nutrition and healthy aging into guidance for the public.
Progress Report
A. As part of our research examining the role of dietary patterns in healthy aging (Objective 1), we examined the relationship of dietary patterns to cognitive health and dementia in two studies. It is known that inflammation in the brain is a hallmark of Alzheimer’s disease with evidence suggesting that it might be involved in the pathogenesis of this disorder, but there is little information on the role pro-inflammatory dietary patterns and the development of Alzheimer’s disease. We investigated this relationship in collaboration with investigators from the University of Texas Health San Antonio, Boston University, Harvard School of Public Health, and New York University. In a large community-based study we observed that higher scores on a dietary inflammation index, which was previously demonstrated to be related to greater peripheral inflammation, were associated with a greater risk of Alzheimer’s disease and all-cause dementia.
B. While there is evidence that diet in older ages may be associated with greater age-related cognitive change, there is little known about the long-term relationship between diet quality and cognitive function. Therefore, in collaboration with investigators from the Tufts Friedman School of Nutrition Science and Policy, we investigated the relationship of a healthy dietary pattern using the Healthy Eating Index and cognitive ability over the life course in a subset of the 1946 British Birth Cohort to identify the life stage when diet may impact cognitive ability most. Our study was the first to examine the trajectory of diet and cognitive ability throughout the lifespan, from age 4 to 70 years, and suggests that the dietary influence on age-related cognitive changes may occur much earlier than previously believed. We observed that those with the worse lifetime cognitive trajectories were most likely to have unhealthy diets whereas those with the healthiest cognitive trajectories were significantly more likely to have consumed the healthiest diets. Our finding also suggests that dietary patterns in midlife, before age 50 years, may be most predictive of cognitive trends up to age 69 years.
C. We continued our research examining the voluntary adoption of popular food group-restricting diets, such as plant-based diets (PBDs) and paleo diets, and the motivation for adoption of, adherence to, and benefits of these diets in the Adhering to Dietary Approaches for Personal Taste (ADAPT) Study. As part of this study, we developed a metric to quantify and compare adherence between self-identifiers of four restriction-type diets – whole food plant-based (WFPB), vegan, vegetarian, and paleo – and applied this score to assess associations between adherence and diet quality (Healthy Eating Index; HEI), body mass index (BMI), and diet maintenance duration. We observed that adherence was lowest in the most restrictive diet (WFPB); however, followers of the stricter diets (WFPB and vegan) had the healthiest mean and range of HEI score and BMI. However, we observed no association between adherence and duration of maintaining the restricted diet. As part of the ADAPT study, we also examined diet quality based on the Healthy Eating Index (HEI) and intake of four designated nutrients of public concern identified by the Dietary Guidelines for Americans 2020–2025 (dietary fiber, vitamin D, calcium, and potassium) in these self-identified followers of popular dietary patterns. We observed that the WFPB and vegan followers had HEI scores well above those of typical American adult diets with vegetarians scoring slightly better and paleo diet followers having scores similar to the typical American diet. Dietary fiber was low among paleo followers and potassium among paleo and vegetarian followers, and even with supplement use, less than 25% of all diet followers met calcium recommendations, and those meeting vitamin D recommendations ranged from 28 percent of vegetarians to 56 percent of paleo followers.
D. In collaboration with colleagues at Boston University, our research on the role of specific foods on healthy aging (Objective 2) demonstrated that greater overall consumption of flavonoid-rich fruits in midlife was associated with reduced risk of developing dementia, although intake of specific fruits in late-life, including citrus fruits and blueberries, may also have a protective role against developing dementia.
E. With collaborators from the Harvard School of Public Health, we evaluated the role of protein consumption and protein sources during middle adulthood in a large cohort of women and observed that dietary protein intake, especially plant protein, in midlife was associated with better odds of healthy aging and with several components of positive health status in this cohort of women. Furthermore, we observed that replacing animal or dairy protein, carbohydrate, or fat with plant protein was associated with better odds of healthy aging, and with higher likelihood of being free of chronic diseases, having good mental health, and not having impairments in either cognitive or physical function.
F. We continued to maintain our long-running program on carbohydrates and healthy aging, with research focusing on the potential long term-health benefits of lower carbohydrate diets to examine if health benefits of lower carbohydrate intakes seen in short-term studies are sustainable over many years and to determine if the benefits of a low-carbohydrate diet are due to reducing overall carbohydrate intake or due to removing low-quality carbohydrate sources. To address these questions, we examined the quantity and quality of carbohydrate intakes over an average follow-up time of 16 years, and showed that consumption of lower carbohydrate diets, regardless of the quality of its sources, were favorably associated with systolic blood pressure but adversely associated with abdominal adiposity. Also, lower carbohydrate diets that maintained high-quality carbohydrate sources were associated with beneficial changes in plasma HDL cholesterol and triglyceride concentrations and low carbohydrate diets that were low in high-quality carbohydrate sources were associated with harmful changes in serum glucose concentrations. We also observed that lower carbohydrates diets that maintained high-quality carbohydrate sources were inversely associated with biomarkers of inflammation and oxidative stress. Overall, our findings support recommendations for preserving high-quality carbohydrates in the context of a lower carbohydrate diet and replacing low-quality carbohydrates with more healthy energy sources.
Accomplishments
1. Investigating foods that may prevent dementia. While there is no conclusive evidence that eating or avoiding a specific food can prevent dementia, including Alzheimer’s disease, ARS-funded researchers in Boston, Massachusetts, have found increasing evidence that suggests diets which emphasize fruits and vegetables, such as a Mediterranean diet, have the potential to reduce the risk of developing dementia. Flavonoids, naturally occurring bioactive pigments found widely in plant-based foods, have shown potential neurocognitive benefits. To further the understanding of the benefits of flavonoid-rich fruits, the researchers examined the associations between midlife and late-life intake of flavonoid-rich fruits and risk of dementia. They observed that greater overall consumption of flavonoid-rich fruits in midlife was associated with reduced risk of developing dementia, and intake of specific fruits in late-life, including citrus fruits and blueberries, may also have a protective role against developing dementia.
Review Publications
Ardisson Korat, A., Shea, K., Jacques, P.F., Sebastiani, P., Wang, M., Eliassen, H., Willett, W.C., Sun, Q. 2024. Dietary protein intake in midlife in relation to healthy aging – results from the prospective Nurses’ Health Study cohort. The American Journal of Clinical Nutrition. https://doi.org/10.1016/j.ajcnut.2023.11.010.
O'Keefe, J., Tintle, N., Harris, W., O'Keefe, E., Sala-Vila, A., Attia, J., Garg, M., Bork, C., Schmidt, E., Venoe, S., Hure, A., Chien, K., Egert, S., Feldreich, T., Arnlov, J., Lind, L., Forouhi, N.G., Geleijnse, J., Pertiwi, K., Imamura, F., Laaksonen, V., Uusitupa, M., Toumilehto, J., Laakso, M., Lankinen, M., Laurin, D., Carmichael, P., Lindsay, J., Leander, K., Laguzzi, F., Swenson, B., Longstreth, Jr., W., Manson, J., Mora, S., Cook, N., Markland, M., Melo Van Lent, D., Murphy, R., Gudnason, V., Ninomiya, T., Hirakawa, Y., Qian, F., Sun, Q., Hu, F., Ardisson Korat, A., Riserus, U., Lazara, I., Samieri, C., Le Goff, M., Helmer, C., Steur, M., Voortman, T., Kamran Ikram, M., Tanaka, T., Das, J., Ferrucci, L., Tsai, M., Guan, W., Garg, P., Verschuren, W.M., Boer, J., Blokstra, A., Virtanen, J., Wagner, M., Yamagishi, K., Siscovick, D., Rozenn, L., Mozaffarian, D. 2024. Omega-3 levels and stroke risk: a pooled and harmonized analysis of 183,291 participants from 29 prospective studies. Stroke. https://doi.org/10.1161/STROKEAHA.123.044281.
Ross, A., Shertukde, S., Livingston-Staffier, K., Chung, M., Jacques, P.F., McKeown, N.M. 2023. The relationship between whole-grain intake and measures of cognitive decline, mood and anxiety - a systematic review. Advances in Nutrition. https://doi.org/10.1016/j.advnut.2023.04.003.
Qian, F., Tintle, N., Jensen, P.R., Lemaitre, R.N., Imamura, F., Feldreich, T.R., Nomura, S.O., Guan, W., Laguzzi, F., Kim, E., Virtanen, J.K., Steur, M., Bork, C.S., Hirakawa, Y., O'Donoghue, M., Sala-Vila, A., Ardisson Korat, A., Sun, Q., Rimm, E.B., Psaty, B.M., Heckbert, S.R., Forouhi, N.G., Wareham, N.J., Marklund, M., Riserus, U., Lind, L., Arnlov, J., Garg, P., Tsai, M.Y., Pankow, J., Misialek, J.R., Gigante, B., Leander, K., Pester, J.A., Albert, C.M., Kavousi, M., Ikram, A., Voortman, T., Schmidt, E., Ninomiya, T., Morrow, D.A., Bayes-Genis, A., O'Keefe, J.H., Ong, K., Wu, J.H., Mozaffarian, D., Harris, W.S., Siscovick, D.S. 2023. Omega-3 fatty acid biomarkers and incident atrial fibrillation: An individual participant level pooled analysis of 17 international prospective studies. Journal of the American College of Cardiology. https://doi.org/10.1016/j.jacc.2023.05.024.
Yuan, J., Liu, X., Liu, C., Ang, A.F., Massaro, J., Devine, S.A., Auerbach, S.H., Krzysztof Blusztajn, J., Au, R., Jacques, P.F. 2022. Is dietary choline intake related to dementia and Alzheimer's disease risk: results from the Framingham Heart Study. The American Journal of Clinical Nutrition. https://doi.org/10.1093/ajcn/nqac193.
Lyu, C., Jacques, P.F., Doraiswamy, M., Young, B., Gurnani, A.S., Au, R., Hwang, P.H. 2024. Flavonoid-rich fruit intake in midlife and late-life and associations with risk of dementia: The Framingham Heart Study. The Journal of Prevention of Alzheimer's Disease. https://doi.org/10.14283/jpad.2024.116.