The role of dietary and blood proteins in the prevention and development of major age-related diseases
Lead Research Organisation:
University of Oxford
Department Name: Population Health
Abstract
The United Kingdom's (UK) population is ageing. As a result, common age-related diseases, such as stroke, fractures and dementia, are predicted to pose an increasing burden on the health system. The development of prevention strategies is therefore an imperative. Emerging evidence has suggested mechanistic links between these age-related diseases. For example, higher risks of hip fractures and dementia have been observed in people who have had a stroke, while a higher risk of hip fractures has also been observed in people who have dementia. These associations may be partly due to the first condition altering the risk of the second condition, but recent evidence suggests that the three conditions might share common risk factors including diet.
Of the potentially modifiable risk factors, differences in the amount and quality of dietary protein intake have been suggested to be important. Specifically, low intakes of high quality protein have been associated with higher risks of haemorrhagic stroke (the more aggressive stroke type) and of hip fractures, possibly because protein is a key structural component for maintaining the strength and integrity of blood vessels and bones. The possible relevance of dietary protein intake in the risk for dementia development has been less studied, but low blood levels of insulin-like growth factor I (IGF-I), a peptide hormone that is known to be influenced by dietary protein intake, have been suggested to increase the risk of dementia as well as stroke and fractures.
Research is needed to understand the effects of dietary protein adequacy and quality on common age-related diseases. This is particularly relevant in light of the global calls to limit animal source food consumption due to their high environmental impact, though these foods are generally considered higher quality proteins. Understanding the exact role of protein adequacy and quality will guide strategies to ensure optimal protein intakes, without compromising sustainability targets.
This research will examine the role of dietary protein intake, focusing on quality as well as quantity, and protein-related biomarkers in the development of stroke subtypes, hip fractures, vascular dementia and Alzheimer's disease, and seek to clarify the links between the three sets of conditions, using data from large prospective cohorts in the UK and in other countries.
The first work package will examine how differences in intakes of dietary protein, protein from different sources and protein rich foods affect the risk of each of the conditions of interest. I will also investigate the role of individual dietary amino acids, which make up dietary proteins, with the aim of investigating the association between protein quality and health.
The second work package will explore how differences in protein intake influence the levels of protein-related biomarkers in the body, and how these biomarkers may be associated with disease risk, as a way of identifying potential disease mechanisms. This will include the examination of established clinical biomarkers (e.g. IGF-I), circulating amino acids and approximately 1500 novel circulating proteins (proteomics). It will also involve the use of genetic instruments to establish the causal relevance of the biomarkers of interest for disease risk.
The third work package will investigate the mechanistic links between the three sets of diseases and the sequence of multimorbidity. I will identify the common dietary and non-dietary risk factors for the three outcomes, and evaluate whether the manifestation of the first condition has a direct effect on the development of multimorbidity, independent of the common risk factors.
Overall, this programme of work will generate robust evidence on modifiable risk factors for common age-related diseases and the potential underlying mechanisms, and inform the optimal targets for strategies in disease prevention.
Of the potentially modifiable risk factors, differences in the amount and quality of dietary protein intake have been suggested to be important. Specifically, low intakes of high quality protein have been associated with higher risks of haemorrhagic stroke (the more aggressive stroke type) and of hip fractures, possibly because protein is a key structural component for maintaining the strength and integrity of blood vessels and bones. The possible relevance of dietary protein intake in the risk for dementia development has been less studied, but low blood levels of insulin-like growth factor I (IGF-I), a peptide hormone that is known to be influenced by dietary protein intake, have been suggested to increase the risk of dementia as well as stroke and fractures.
Research is needed to understand the effects of dietary protein adequacy and quality on common age-related diseases. This is particularly relevant in light of the global calls to limit animal source food consumption due to their high environmental impact, though these foods are generally considered higher quality proteins. Understanding the exact role of protein adequacy and quality will guide strategies to ensure optimal protein intakes, without compromising sustainability targets.
This research will examine the role of dietary protein intake, focusing on quality as well as quantity, and protein-related biomarkers in the development of stroke subtypes, hip fractures, vascular dementia and Alzheimer's disease, and seek to clarify the links between the three sets of conditions, using data from large prospective cohorts in the UK and in other countries.
The first work package will examine how differences in intakes of dietary protein, protein from different sources and protein rich foods affect the risk of each of the conditions of interest. I will also investigate the role of individual dietary amino acids, which make up dietary proteins, with the aim of investigating the association between protein quality and health.
The second work package will explore how differences in protein intake influence the levels of protein-related biomarkers in the body, and how these biomarkers may be associated with disease risk, as a way of identifying potential disease mechanisms. This will include the examination of established clinical biomarkers (e.g. IGF-I), circulating amino acids and approximately 1500 novel circulating proteins (proteomics). It will also involve the use of genetic instruments to establish the causal relevance of the biomarkers of interest for disease risk.
The third work package will investigate the mechanistic links between the three sets of diseases and the sequence of multimorbidity. I will identify the common dietary and non-dietary risk factors for the three outcomes, and evaluate whether the manifestation of the first condition has a direct effect on the development of multimorbidity, independent of the common risk factors.
Overall, this programme of work will generate robust evidence on modifiable risk factors for common age-related diseases and the potential underlying mechanisms, and inform the optimal targets for strategies in disease prevention.
