Dr. Jen Bradley

The state of a nation’s dietary habits often makes the news headlines. But how do we know what people are eating and drinking? Dietary assessment is the collection of information on food and drink consumption from an individual or a group of people and the evaluation of this information to assess nutrient intake and dietary patterns. In nutritional epidemiology, dietary assessment methods are needed to obtain food intake data from a large population of individuals to investigate dietary exposure – these findings sometimes make the news.

My research is based on self-reported dietary assessment, which means the data we collect is based on people recalling or recording what they consume. Dietary assessment has changed a lot in recent years and I have observed this change. When I started working as a research assistant at HNRC (before it gained the ‘E’) in 2008, dietary assessment was an arduous task and quite cumbersome at times! Conducting dietary interviews with secondary school pupils required a car boot full of equipment; paper food diaries, food portion photos and food models. In addition, finding a suitable space for us to work in, in a busy school environment was not always easy. After weeks working in schools we would have a pile of completed paper food diaries and would spend months of project time linking the foods and drinks in the diaries to a nutrient food code (to allow us to look at nutrient intakes) and then more time entering these onto a database. Eventually we would have some dietary intake data to analyse!

Fast forward 16 years, and dietary assessment is a much more streamlined process. Intake24 is an online dietary recall system. I worked on the initial development and testing of the tool, which was led by Dr Emma Foster and Prof Patrick Olivier at Newcastle University. Research participants can log on to the website and enter all the foods and drinks they consumed the previous day. There are 1000s of foods in the system which users can select from and choose the portion size eaten by clicking on the relevant photo. The system has been created to be as close to an in-person interviewer-led recall as possible, for example the system prompts for any additions to foods which are commonly forgotten, such as ketchup on chips, milk on cereal, sugar in tea. If there are long gaps between meals, the user will be prompted to think if they had anything to eat within that time.   

One of the many advantages of Intake24 compared to the traditional paper-based methods, is the ability to collect dietary data from 1000s of study participants remotely. Arranging suitable times to meet with participants to conduct dietary interviews is no longer a requirement and saves hours of researcher time. Intake24 automatically codes the food and drink intakes, therefore dietary data can be downloaded from the system immediately, removing the laborious task of food diary coding and data entry onto a database. This also improves consistency of nutrient coding and removes human error. The development of Intake24 has changed the way dietary intakes are collected globally. The system is being used in the UK National Diet and Nutrition Survey and national surveys in Australia and New Zealand. Versions have been created for Portugal, Denmark, Malaysia, Indonesia and Japan.

However, I have a small confession. I miss meeting study participants. I always had a great deal of fun talking about what they had eaten and the little conversations they led to. In a pilot study for the Diet and Nutrition Survey of Infants and Young Children I met many parents of young babies and infants and it was an absolute joy to talk about foods their infants were eating and funny anecdotes about food flying onto ceilings and how on earth they were meant to measure the amount eaten when half of it was soaked into the bib! Dietary interviews with school children were always enlightening and again often led to interesting conversations about favourite foods and drinks. There is an argument, however, that removing the researcher from the dietary collection process, reduces the risk of social desirability; participants who may not have recorded that extra biscuit, might feel they can be more honest without a researcher present.

I remember the first time I downloaded dietary data from Intake24 during the testing of the tool in 180 participants in Scotland. At the end of a very busy few weeks collecting data from participants, I clicked the download button, and everyone’s food and nutrient intakes were there on the screen right in front of me. I didn’t need to cart a pile of food diaries and food models around with me, spend hours coding them and entering them into a database. I realised that Intake24 was going to vastly improve the process of dietary assessment, and importantly help make dietary assessment possible in large population-based studies where the cost of traditional methods would have previously been prohibitive. It was a moment I won’t forget, and I am so proud to have played a small part in its very successful journey so far.

The Power of Connection: Exploring Support in Performance and Health

Supporting others, or getting support, can be beneficial in lots of ways. It helps build and maintain relationships and allows us to feel connected to the people around us. This support can help every one of us, including people trying to become physically active, or to improve self-confidence and performance.

But are we comfortable opening up and asking for help? Do we really know the intricacies of support and how it should be provided or perceived? What are the effects of support for different populations?

Beyond SMART Goals: Tailoring Motivation Interventions

Goal setting has been shown to be beneficial for helping develop and maintain motivation in a variety of settings. Although recent research suggests a one-size fits all approach to goal setting might not lead to sustained change, particularly for an inactive population.

What innovative alternatives might be available to us? How might we design goals for clinical populations looking to improve physical activity?

Behind the Scenes: Unveiling the Science of Support in Health and Performance

Dr Adam Coussens, of Newcastle University, has been addressing these types of questions from his PhD focussing on social support of athletes, through to his recent research applying support and goal setting principles in different populations, including emergency services. Adam also co-hosts the internationally attended conference, Psychological Insights into Coaching Practice. This blog will focus on one current project Adam is working on, an intervention to improve physical activity levels in heart failure patients.

Adam has collaborated with fellow researchers from Teesside University, Newcastle University, and healthcare professionals from NHS Trusts across the north-east, as part of the BeActive Heart Failure group. Adam is working on this Heart Failure UK funded feasibility project to provide resources and support to people to understand the barriers within cardiac rehabilitation, and subsequently promote physical activity and cardiac rehabilitation uptake.

Adam has been working with healthcare professionals leading tailored workshops, equipping them with the tools to guide their patients towards utilising social support and setting effective goals. These workshops emphasise the crucial role of perceived and received support, identify potential gaps, and offer strategies for effectively utilising existing networks. Furthermore, practical guidance is provided on how to set more ‘open’ and ‘do your best’ goals, to help maintain motivation and physical activity.

What is Next for the Project?

Physical activity levels of heart failure patients involved in the project are being monitored using Actigraph measures. Interviews will also take place with healthcare professionals who delivered the intervention, and heart failure patients, to evaluate the effectiveness and practicality of this project.

As this is currently a feasibility study, the aim is to develop the multidisciplinary intervention further to include more NHS Trusts and identify whether a BeActive-HF intervention could be used as part of routine clinical care for patients with heart failure.

Reposted with permission from the Newcastle University Extreme Environments Group blog (https://blogs.ncl.ac.uk/extremeenvironments/blog-why-is-the-kona-ironman-world-champs-so-hard-for-the-pros/)

Hawaii is the birth place of the IronMan triathlon where in 1978 Judy and John Collins challenged individuals to swim bike and run 140.6 miles and joked they would call the winner an “Iron man”. The event now sees 1000s of athletes test themselves in IronMan races all over the globe, including myself. But Kona, home to the Ironman World Championships which begins today (6^th October 2022), holds something special for all triathletes. The history of the race is full of epic tails of survival (see the story of Julie Moss or Sian Welsh & Wendy Ingraham) and infamous battles such as the Iron War (between Dave Scott and Mark Allen). The weather is generally consistent and therefore predictable in Kona in October: sunny, windy and humid. However, while the air temperatures are generally around 30 ^oC which are not necessarily remarkable, it is the humidity “swamp-like” conditions that really challenge athlete’s thermoregulatory capacity when competing in the Ironman World Championships.

So why is Kona so hard?

It is well established that heat will reduce exercise performance incrementally, mediated by increasing heat gain and a rise in core body temperature. When athletes are faced with hot environments, preparation strategies such as heat acclimation facilitate heat tolerance which drive a range of physiological adaptations to help them tolerate heat. However, it is an adaptive increase in sweat rate that facilitates the greatest heat loss. Heat transfer is mediated by evaporation of sweat from the skin which transfers heat away from the body. In fact, when all sweat is able to evaporate from the skin (we will call this ideal conditions – typically dry-hot) heat is removed at a rate of 2.34 kJ/g. The human body can produce sweat at rates approximating ~ 30 g/min (losses in body mass equivalent to ~ 1.5-2 L/hr). Although, if you have been keeping up to date with Lionel Sanders vlog he mentions much higher changes in body mass after training that indicate sweat losses of ~2.5 L/hr. However, if using our sweat rate value of ~ 30 g/min this equates to removing heat at 73 kJ/min (~1219 W). The human body has only ~ 20% efficiency therefore this reported heat loss would support normothermic total energy use of 1520 W. As a result external work rate would be equivalent to ~ 305 W (20% of total energy use). Athletes across a number of social media platforms discuss numbers in the range of 300-350 W for average sustainable power during the cycling portion of an IronMan, meaning that in ideal conditions these numbers are perfectly reasonable and heat gain can be controlled (being mindful of dehydration of course).

Post race edit: Sam Laidlow beat the bike course record with a time of 4 hr 4 min and reported average power ~315 W. source: https://www.youtube.com/watch?v=njUjiu_AOeA].

However, the big problem in Kona, like we have said, is the humidity. Kona may see humidity in the range of 80-90% (30 ^oC air temp at 90% RH = WBGT ~ 28.6 ^oC) meaning the air contains a greater amount of water vapor thus reducing the gradient for evaporative heat transfer. This means our ideal scenario no longer holds true and the ability to dissipate heat decreases. It is the efficiency of sweating, defined as the ratio between secreted and evaporated sweat that is reduced as humidity increases, with some studies indicating that efficiency can decrease by ~35 % when humidity increases from 50 to 70% (Alber-Wallerstron & Homer, 1985; Frye & Kamon 1983). Clearly if humidity tops 90% the athlete’s sweat efficiency will be further reduced. As a result, athletes gain heat more quickly, core temperature increases more rapidly reaching critical limits facilitating a drop in exercise intensity and potentially leading to hyperthermia or more serious consequences. Indeed, Jan Frodeno, arguably the best IronMan athlete of all time, famously said that his rule of thumb is to take 15-20% off his normal wattage on the bike to account for the extreme heat stress in Kona.

So, what are the anticipated conditions in Kona?

Over the past 3 days humidity has ranged from 65 to 94% relative humidity, with temperatures ranging from 25-30 ^oC during the approximate times the professional athletes will race (6am-3pm) (https://w1.weather.gov/data/obhistory/PHKO.html – accessed 5/10/22 23:00). Whilst athletes and coaches are much more aware of the impact of heat stress and humidity in Kona, we will probably still see the breakdowns and collapses in the professional field that we are so accustomed to seeing at Kona. Science and technology, with respect to maximising heat tolerance, has pervaded the sport in recent years with the Norwegians taking the game to another level and other professionals following suit. It will be fascinating to see who has prepared the best, what strategies they adopt and who’s body can tolerate the conditions best. It will be a great race to watch! My money is on Daniela Ryf or Lucy Charles-Barclay in todays race and in the men’s race on saturday its the Big Blu although really hope Sanders has the race he capable of.

Updated 06/10/22 18:00 – Women’s environmental conditions at start of swim – as predicted 24 ^oC and 88% humidity.

Updated 08/10/22 – Men’s environmental conditions at start of swim (~6:00am left) and at the start of the run (~10:44am right) – as predicted temps increased from 24 to 28 ^oC and humidity remained stable around 85%.

Written by Owen Jeffries

On 19^th-20^th June 2023, the inaugural Eatwell Guide Forum was hosted at the Human Nutrition and Exercise Research Centre (HNERC) at Newcastle University. The event was funded by Rank Prize, following application from a project team of UK-based researchers. Dr. Oliver Shannon led the application as principal investigator, supported by co-investigators; Dr. Fiona Malcomson and Dr. Rebecca Townsend (of Newcastle University), Dr. Sarah Gregory (Edinburgh University), Dr. Jamie Matu and Dr. Alex Griffiths (both of Leeds Beckett University), Dr. Amy Jennings and Ms. Nicola Ward (both of Queen’s University Belfast).

This application followed previous work conducted by the project team, which investigated associations between adherence to the Eatwell Guide and outcomes of cardiometabolic and cognitive health, including neuroimaging measures in the PREVENT Dementia cohort. This work was funded by the NuBrain Consortium led by Prof. Emma Stevenson, and contributes toward the limited number of studies which evaluates adherence to recommendations within the Eatwell Guide in relation to health outcomes. Acknowledging this, the project team believed it would be invaluable to host an event which aimed to both consolidate existing knowledge, and set the agenda for future work, surrounding the Eatwell Guide and outcomes of human and planetary health.

The Forum was attended by twenty-one researchers/professionals who travelled to Newcastle-upon-Tyne by train, plane, and van, from across all corners of the UK. A further three individuals attended the event virtually, including colleagues from international locations.

The event kicked off with an introduction to the Forum from the organising committee, who welcomed attendees and set out the agenda for the day. Prof. Louis Levy then gave an engaging keynote talk about the evolution of the Eatwell Guide and the extensive research which underpinned this process, spanning from idea conception to testing and validation of the tool. After a much-needed coffee-break (some attendees had 3am starts!), the first original research session began. This session explored how adherence to the Eatwell guide could impact population health, including outcomes of mortality (Dr. Keren Papier), adiposity (Dr. Nicola Best) cognitive function/brain health (Dr. Sarah Gregory) and risk of falls (Ms. Chloe French).

Following a plentiful lunch break packed with networking and further introductions, the second session began. This session was angled toward exploring the impact of the Eatwell Guide on planetary health. Dr. Pauline Scheelbeek highlighted the potentially beneficial influence of the Eatwell Guide on greenhouse gas emissions, and Dr. Curie Kim reviewed the evidence surrounding the Eat-Lancet Reference Diet (a diet developed to promote environmental sustainability) in relation to cognitive function. After further discussions and an afternoon break, the third and final session of the day commenced. Prof. Bertha Ochieng and Fareeha Jay presented the work they have each undertaken to culturally adapt the Eatwell Guide, in order to improve representation across various communities living within the UK. This included the co-creation of an African Heritage Eatwell Guide and the development of a South Asian Eatwell Guide. The first day of the Forum ended with a stimulating audience discussion surrounding the past, present, and future opportunities in relation to the Eatwell Guide. Event attendees then had a taste of the Newcastle dining scene to complete the first day of the Forum and enjoyed further networking opportunities.

The second day of the Forum opened with a recap of day one from the organising committee, followed by commencement of the fourth original research session. Presenters discussed the potential application of the Eatwell Guide within future clinical trials (Dr. Amy Jennings) and outlined the development of new methods to determine adherence toward recommendations within clinical and public health settings (Ms. Kaydee Shepherd).

Event attendees then participated in a world café-style activity to highlight gaps in current knowledge and outline future opportunities for further research. Discussions were had about the overall paucity of research which investigates adherence to the Eatwell Guide, in relation to both human and planetary health outcomes, especially within specific sub-group populations at increased risk of diet-related diseases. Attendees also commented on the methods to assess the level of implementation of the Eatwell Guide at population-level, including examination of understanding among both the public and healthcare professionals. Following conclusion of the activity, the Forum ended with a general discussion surrounding key principles to consider when conducting future research. The importance of input from patient and public involvement (PPI) panels was highlighted, to promote acceptability, understanding and enhance usability of the Eatwell Guide. Ultimately, the need to develop cross-disciplinary relationships which span outside of academia, including relevant governmental departments and industry partners (e.g., consumer data panels) was acknowledged.

Overall, the event was a great success and helped many to develop new connections and acted as a catalyst for the initiation of novel and exciting ideas surrounding the Eatwell Guide. The event was also live scribed by Beka Haigh, who expertly sketched the final graphic shown below to neatly summarise the content of the Forum. Finally, the organising committee and event attendees intend to write a formal summary of the Forum, for submission to the Nutrition Bulletin – so keep an eye out for this!

A new project outline with Dr. Sam Orange (reposted with permission from Breastcancernow.org)

The challenge

More women are living with and beyond breast cancer than ever before. But they often experience long-lasting low mood or extreme tiredness (fatigue), even after their treatment has ended. It can dramatically affect their quality of life.

Leading a healthy lifestyle after a breast cancer diagnosis and treatment can help with this. And it could lower the risk of breast cancer coming back. Despite this, there’s little support available to help women maintain regular physical activity and a healthy diet.

The science behind the project

Dr Sam Orange, from Newcastle University, wants to improve women’s access to diet and physical activity support after their breast cancer treatment. There are many barriers that prevent women from getting this support in the National Healthcare System (NHS), such as limited resources, no referral pathway, and there being no support services to refer them to at all.

Sam’s creating a referral pathway so that healthcare professionals can refer women to community support services. And he’s developing a training package to help community services adapt their health and lifestyle programmes to specifically support women after breast cancer treatment.

To do this, the researchers will first identify existing diet and physical activity services in the community that could be adapted. They’ll look at how they’re accessed, funded and how well they work.

Then they’ll hold 4 focus groups to explore different people’s experiences of accessing and giving support. These focus groups will include women who have finished treatment for early-stage breast cancer, healthcare professionals, dieticians and exercise specialists, and community practitioners.

The third stage of the project will involve 4 workshops based on the results of earlier stages. They’ll bring women who have finished treatment for breast cancer and healthcare professionals together to talk about how community services could be adapted. And how the referrals could work.

Finally, the researchers will test how well the new programme works. They’ll ask healthcare professionals to refer 40 women to the adapted diet and physical activity service. They’ll see how women feel about the service and get perspectives from community practitioners and healthcare professionals as well.

What difference will this project make?

If this project is successful, the researchers will carry out a larger study to directly measure if this programme leads to better quality of life for women living with and beyond breast cancer. And it may also help to reduce their risk of a second breast cancer diagnosis.

How many people could this project help?

55,000 women are diagnosed with breast cancer each year in the UK. This project has the potential to help all of them to maintain healthy diet and physical habits. But it could especially help the 1/3 of women that experience persistent fatigue after treatment, as well as the 48% of women that experience depression and anxiety.

For the original post, see: Breast Cancer Now

Dr. Oliver M Shannon, Human Nutrition & Exercise Research Centre, Newcastle University

When I was young, I loved to spend time with my grandad.  He was full of energy, had a wicked sense of humour, and was always there when you needed him.  He was in great health throughout most of his life, and he was still running half marathons well into his 70’s. However, when he was 85, my grandad had a stroke.  Shortly after, he was diagnosed with dementia and his short-term memory began to decline. Over time, other bodily functions did too, and he sadly passed away in January of this year. 

This is a short-hand version of my own personal experience of dementia.  Millions of other people have a similar story.  You may do too.  Indeed, right now there are over 55 million people in the world living with dementia, placing a huge and unsustainable burden on individuals, their families and society at large.

Although promising findings are starting to emerge, at present, there are very few options available for treating dementia.  As such, many researchers are focused on identifying ways to help people reduce their risk of developing this condition. 

The 2020 Lancet Commission Report on dementia prevention outlined 12 modifiable risk factors, which collectively account for around 40% of dementia cases worldwide, and could be targeted by policy makers and individuals to help reduce dementia risk.  These risk factors include low education levels, hearing loss, brain injury, high blood pressure, high intake of alcohol, obesity, smoking, depression, social isolation, physical inactivity, air pollution, and diabetes. 

Although this report identifies a high intake of alcohol (a dietary factor) and conditions such as obesity and diabetes (which may be linked with diet) as key dementia risk factors, it is notable that consumption of an unhealthy diet as a whole is absent from the list of modifiable risk factor for dementia.  This is despite mounting evidence that what we eat can impact brain health throughout the life course. 

There are a few reasons why diet might not play a more prominent role in the Lancet Commission report.  This includes the difficulties in defining what a healthy/unhealthy diet looks like, and the fact that not all studies have shown convincing links between diet and brain health.    There is therefore a need for more research to help us understand whether what we eat can have a meaningful effect on dementia risk.  Likewise, it is important to identify whether there are certain people who might benefit more or less from making changes to their diet. 

For some time, we (and many others) have been interested in the potential health benefits of eating a Mediterranean-like diet, which is rich in healthy plant-based foods like fruits and vegetables, pulses, nuts, olive oil and also includes plenty of fish.  Numerous studies, including the influential PREDIMED trial in Spain, have shown that eating a Mediterranean diet can improve cognitive (brain) function in older adults.  Similarly, a handful of studies have suggested that eating a Mediterranean diet could help reduce the risk of developing dementia.  However, the links between a Mediterranean diet and dementia risk are far from conclusive.  Moreover, most studies to date have been fairly small and have provided limited insight into whether certain individuals (for example, those with different genetics) might respond differently to consumption of a Mediterranean diet. 

To address some of these issues, we recently explored the associations between adherence to a Mediterranean diet and dementia risk in over 60,000 participants from the UK Biobank.  Using dietary data from the participants, we were able to give each individual a score ranging from 0 to 15 to define how closely their diet matched the key features of a Mediterranean diet (those with higher scores had a more Mediterranean-like diet).  We then used a statistical technique known as Cox proportional hazard regression to explore associations between the level of Mediterranean diet adherence and risk of developing dementia over a ~9 year period, whilst controlling for potential differences in factors such the education level and physical activity status of participants. 

We found that individuals with higher adherence to the Mediterranean diet, as defined by one of the Mediterranean diet scores known as the MEDAS continuous score, had a 23% lower risk of developing dementia than those with lower adherence to a Mediterranean diet. 

Interestingly, there were similar associations between Mediterranean diet adherence and dementia risk in individuals with higher and lower genetic risk for this condition.  This suggests that, even for those with higher genetic risk, having a more Mediterranean-like diet could help reduce the likelihood of developing dementia. 

Our study has a number of strengths, not least it’s size and the comprehensive way in which we defined genetic risk for dementia (using an approach called a polygenic risk score).  However, no study is without limitations. Most notably, as this was an observational study, we cannot infer cause and effect from our findings. 

Much more research is needed to identify the best diet that people could follow to try and reduce their risk of dementia.  However, the findings from our study contribute towards a growing body of evidence to suggest that following a more Mediterranean-like diet could be an effective way to help ‘oil your cogs’ and reduce your risk of developing dementia. 

Anyone who has spent time in research will tell you that some of the most important and highly skilled members of the research team are the laboratory technicians, without whom university research would grind to a halt.

In this blog we provide an insight into a day in the life of the Sport and Exercise Science Technicians within the HNERC.

5/6am: Our alarms go off bright and early to make sure we get to the gym/go out for a run before we start work (some of us are more committed than others!).

7am: After a sleepy walk/ metro journey into work, we get to the gym at around 7am and train for around an hour.

8am: Time for a quick shower, hair done, and we are ready to start the morning!

8am-12 (dinner): Mornings are usually our busiest time in the labs. We have UG and MSc classes scheduled most days throughout Semester 1 and 2, (usually a 9am start) and ensuring equipment and facilities are prepared is a major part of our role. We enable, check and calibrate all of the equipment that is needed for the day to ensure it’s ready to go for the students and our academic colleagues to use. We have at least 2/3 repeats of a class each day so as soon as one is done, equipment is cleaned, recalibrated, and reset ready for the next students coming in. As well as taught classes, we support staff and student research projects. It is here that our lab skills are utilised the most, we provide training, demonstrations and more recently, some of us have completed training in both venepuncture and cannulation and therefore provide phlebotomy support to a range of projects across the whole faculty.

Dinner time (most important part of the day!): We are all a bit obsessed with asking what we have for lunch, so dinner time is a very important part of our day! We catch up with one another/ other colleagues and try and have some downtime before the afternoon starts.

12:30-3pm: After lunch we catch up with any emails/lab booking forms and get ready for any classes scheduled on the afternoons.  The team have their own roles and responsibilities, and this time of day is generally used to fulfil these. For example…

• Alex is currently working on his application to gain his HEA Associate Fellowship qualification
• Jordan is supporting two projects, the first of which is investigating appetite responses to different protein sources in older adults, and the second is looking to determine the necessary centrifugation required to ensure acellular plasma.
• Will is preparing for his PhD in neuromuscular physiology, looking at the concept of durability and fatigue in endurance sports.
• Steve is currently working on setting up a consultancy service to perform biomechanical analysis on elite level golfers. Also, Steve is learning how to code using MatLab which will be beneficial for when he starts his PhD, looking at translating motion capture into real world settings using inertial measurement units.
• Ross leads both the SES and Nutrition technical teams and has recently completed his professional services development programme. Ross is also the school health and safety officer, so he is always keeping us on our toes!

As technicians, we have to be very adaptable and flexible; students and staff can need help with equipment/ anything lab based at any point in the day so we usually have to prioritise tasks as and when they arise and work around this.

3 -5 pm: We try to plan ahead and make sure we are as prepared as possible for the next day so we check the calendar and get everything ready for the next morning.

Home time – we head off home to relax and spend time with our friends and family ?

By Giorgia Perri

My PhD within the Human Nutrition & Exercise Research Centre is now coming to an end which has allowed for reflection on my learning and understanding during the programme. My PhD focused on the effect of nutrition, specifically selenium, on musculoskeletal ageing. Before I embarked the PhD programme, like many others, I did not know a whole lot about selenium. I’d noticed it on some multivitamins I was taking, but after reading about this essential micronutrient, it soon became clear how important selenium is for human health, and how it could be involved in the ageing processes of muscle and bone. Selenium is incorporated into the human body as selenoproteins which exert different effects. Most selenoproteins have antioxidant effects that can mitigate the negative effects of excessive reactive oxygen species such as DNA damage. With age there is an increase in these reactive oxygen species which is thought to contribute to the ageing phenotype and disease, including reduced musculoskeletal function. It’s crucial that research is maintained in this area as populations are on the rise and living longer, but not necessarily in good health. One major issue older adults face is a decline in their musculoskeletal function, which can be associated with osteoporosis and sarcopenia. The rationale behind my PhD was further enhanced as experiments involving animal models had found effects of selenium deficiency or supplementation on musculoskeletal function. For example, in selenium-deficient rats, studies have found abnormal skeletal growth and poor bone health ^1,2 and lower bone mineral density and femur ash weight ³.

Despite these experimental findings, the research was, and still is, lacking in human studies. A handful of promising observational studies have found associations between low serum selenium and markers of musculoskeletal strength like hand grip strength ⁴ and bone mineral density in older women ⁵ and older men ⁶. However, none of these studies to date have explored the long-term effects of selenium, analysed a variety of selenium doses or biomarkers of status or studied very old adults (≥ 85 years). This is what my PhD involved through exploring the effect of selenium on MSK ageing using two different study designs, observational (prospective) and experimental (randomised controlled trial).

The prospective analyses of my PhD used data obtained from the Newcastle 85+ Study. This was a large, longitudinal, single-birth year cohort residing in Newcastle upon Tyne. The study set out to explore the health trajectories of very old adults (≥ 85 years) and factors influencing these. During my MRes analyses I used the same data exploring the effect of dietary selenium intake on musculoskeletal function. Over half of the participants were consuming below the lower reference nutrient intake, a recommended intake to meet the needs of 2.5 % of a population, which equates to 40 µg/d ⁷. At baseline, those with lower intakes were associated with lower hand grip strength, but the association was not maintained during the 5 year follow up. This initial analysis was helpful in discovering that, as suspected, selenium intakes were suboptimal in very old adults, however, there are some limitations to dietary nutrient estimations, therefore, serum biomarkers of selenium status were measured as part of my PhD in 757 samples. These were analysed at Charité University, Berlin in Prof Lutz Schomburg’s lab that I also got to visit and found really interesting. The biomarkers of selenium status were serum selenium and two selenoproteins, glutathione peroxidase 3 (GPx3) and selenoprotein P (SePP).

Like the suboptimal selenium intake, this population also had suboptimal selenium status for serum selenium, however, surprisingly, GPx3 activity was considered adequate. It was also found that the selenoproteins were correlated linearly with serum selenium, further suggesting a lack of full selenoprotein expression. Taking this further, the associations between the biomarkers of selenium status and musculoskeletal function were explored. At baseline, there was no association between biomarkers of selenium status and hand grip strength or physical performance. However, there were negative associations between each of the selenium biomarkers and disability and GPx3 activity at baseline was negatively associated with change in prevalence of sarcopenia after 3-year follow-up.

The experimental analyses of my PhD used data obtained from the PRECISE study. This was a large, placebo-controlled randomised controlled trial using selenium-yeast supplementation in different doses (100, 200, 300 µg/d) for 5 years in 481 participants. In this study, plasma selenium was measured and retrospectively, biomarkers of bone turnover were measured. Selenium increased plasma selenium in a dose-dependent manner, suggesting good compliancy to the supplementation. However, supplementation had no significant effect on the bone turnover markers. This may be since the populations baseline selenium was 86.5 µg/l which is considered adequate whereby supplementing on top of this may provide no additional benefit. This was published in Journal of Bone and Mineral Research, see the link here https://pubmed.ncbi.nlm.nih.gov/36093566/

My PhD contributed to the field of research in selenium and musculoskeletal function by enhancing previous knowledge for example using longer study durations or more biomarkers of selenium. Despite the lack of significant findings it is still important to note the suboptimal selenium status in very old adults which requires attention for health optimisation. I would like to explore this further looking at other musculoskeletal outcomes, such as falls and fractures.

References

1. Moreno-Reyes, R., Egrise, D., Nève, J., Pasteels, J. L., Schoutens, A. (2001) ‘Selenium deficiency-induced growth retardation is associated with an impaired bone metabolism and osteopenia’, Journal of Bone and Mineral Research, 16, pp. 1556-1563.
2. Hurt, H. D., Cary, E. E. and Visek, W. J. (1971) ‘Growth, reproduction, and tissue concentrations of selenium in the selenium-depleted rat’, J Nutr, 101(6), pp. 761-6.
3. Sasaki, S., Iwata, H., Ishiguro, N., Habuchi, O., & Miura, T. (1994) ‘Low-selenium Diet, Bone, and Articular Cartilage in Rats’, Nutrition, 10(6) pp. 538-543.
4. Beck, J., Ferrucci, L., Sun, K., Walston, J., Fried, L. P., Varadhan, R., Guralnik, J. M. and Semba, R. D. (2007) ‘Low serum selenium concentrations are associated with poor grip strength among older women living in the community’, BioFactors, 29(1), pp. 37-44.
5. Hoeg, A., Gogakos, Apostolos, Murphy, Elaine, Mueller, Sandra, Köhrle, Josef, Reid, David M., Glüer, Claus C., Felsenberg, Dieter, Roux, Christian, Eastell, Richard, Schomburg, Lutz, Williams, Graham R. (2012) ‘Bone turnover and bone mineral density are independently related to selenium status in healthy euthyroid postmenopausal women’, The Journal of clinical endocrinology and metabolism, 97, pp. 4061-4070.
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