Dr. Kirsty Reynolds

The last few years has seen increasing participation in endurance sporting events such as running half-marathons and marathons and even ultra distance events (Scheer., 2019). However, exercising over such long durations requires a substantial energy demand (ranging between ~4000-11000 kcal for ultra-endurance events; Barrero et al., 2014; Costa et al., 2019 ) and without regular intake of energy via food and fluids it will be harder to maintain the same pace due to depleted energy stores, onset of fatigue ultimately leading to a decline in performance.

At higher exercise intensities (>60% V̇O_2max) carbohydrate is the preferred fuel source (van Loon et al., 2001). Whilst we can store carbohydrate in our muscles and liver to help fuel performance, these stores are limited. Sports nutrition research has formed guidelines providing information on carbohydrate dose and sugar type (e.g., glucose and fructose) varying depending on exercise duration (Burke et al., 2011). Exercise durations exceeding 45 minutes it is recommended to consume carbohydrate with doses starting at 30-60 g/h using glucose only to 90 g/h consuming glucose and fructose. For context, a commercially available carbohydrate gel consumes ~30-40g of carbohydrate, meaning to reach the recommended intakes using only carbohydrate gels you would need to be consuming ~2-3 gels every hour. However, there is research in support of using food first approaches, demonstrating that performance is not impacted by choices to eat bananas, raisins, chocolate etc instead of specific sports nutrition products (Reynolds et al., 2022). This can also provide greater variety when fuelling performance to help prevent taste and texture fatigue.   

During exercise blood flow is redistributed towards working muscles and away from the gut. This can have negative implications for athletes with approximately 30% of endurance athletes and especially female athletes reporting gastrointestinal symptoms. This is known as Exercise-induced Gastrointestinal Syndrome (EIGS) and includes symptoms such as stomach cramps, nausea and diarrhoea. The ingestion of carbohydrate can exacerbate symptoms, and this can be disastrous for performance and can even contribute to failure to complete endurance events. However, the gut is considered to be a ‘trainable organ’ and regular consumption of carbohydrate during training can help reduce the likelihood of symptoms (Jeukendrup., 2017).

Additional factors to consider include hydration and the external environment. Global warming and climate change mean that most of the world will experience warmer temperatures which is a cause for concern. Dehydration independently of carbohydrate availability can decrease performance so the use of integrated fuel and fluid such as carbohydrate drinks to maintain hydration status and provide fuel, especially in warm conditions. Furthermore, we recently have shown that when exercising in warm conditions we have a greater reliance on the stored carbohydrate within our body even when carbohydrate is provided (Reynolds et al., 2025; Mougin et al., 2025). Meaning that pre and post exercise greater carbohydrate consumption may be required.

References:

Barrero A, Erola P, Bescós R. Energy balance of triathletes during an ultra-endurance event. Nutrients. 2014 Dec 31;7(1):209-22. doi: 10.3390/nu7010209.

Costa RJS, Knechtle B, Tarnopolsky M, Hoffman MD. Nutrition for Ultramarathon Running: Trail, Track, and Road. Int J Sport Nutr Exerc Metab. 2019 Mar 1;29(2):130-140. doi: 10.1123/ijsnem.2018-0255.

Jeukendrup AE. Training the Gut for Athletes. Sports Med. 2017 Mar;47(Suppl 1):101-110. doi: 10.1007/s40279-017-0690-6.

Mougin L, Horner M, Edwards D, Nickels M, Taylor L, James LJ, Mears SA. Heat stress impairs exogenous carbohydrate oxidation during prolonged running when maintaining euhydration. J Appl Physiol (1985). 2025 Dec 1;139(6):1436-1446. doi: 10.1152/japplphysiol.00873.2025.

Reynolds KM, Clifford T, Mears SA, James LJ. A Food First Approach to Carbohydrate Supplementation in Endurance Exercise: A Systematic Review. Int J Sport Nutr Exerc Metab. 2022 Mar 1;32(4):296-310. doi: 10.1123/ijsnem.2021-0261.

Reynolds KM, Funnell MP, Collins AJ, Mears SA, Pugh JN, James LJ. A Warm Environment Reduces Exogenous Glucose Oxidation and Endurance Performance during Cycling with Facing Airflow. Med Sci Sports Exerc. 2025 May 1;57(5):1043-1055. doi: 10.1249/MSS.0000000000003632.

Scheer V. Participation Trends of Ultra Endurance Events. Sports Med Arthrosc Rev. 2019 Mar;27(1):3-7. doi: 10.1097/JSA.0000000000000198.

By Dr. Deb Dulson

With winter now in full swing, so too are the ‘winter bugs’ that can cause a number of infections and illnesses, the most common of which being upper respiratory tract infections (URTI) such as cold and flu. Cold and flu are more prevalent during the winter months due to the favourable conditions for these viruses to survive and replicate. While the cold and dry (little moisture/humidity) air during winter is advantageous for pathogens, it is not so great for us or our mucosal immune system (which consists of mucus membranes lining our internal surfaces such as nose, mouth, eyes, lungs etc. that are exposed to the external environment). Cold dry air can lead to the drying of several mucus membranes, causing damage and inflammation to occur.

Add to this, the increased amount of time we spend indoors with other people during winter due to the adverse weather, and it is unsurprising why our risk of illness is significantly higher during winter than other times of the year. Work by my group has shown that the greatest predictor of URTI risk amongst elite athletes was not related to training stressors or wellness indicators, but to household illness. In fact, an athlete’s risk of URTI was increased 3-6 times if a member of their household was ill ^[1,2]. This finding aligns with broader trends in the general population.

So, how can you reduce your chances of illness this winter?

While the immune system is incredibly complex, there are some straight forward strategies we can implement to give this system the best fighting chance of keeping us healthy this winter. Although the following strategies have been proposed with the immune system in mind ^[3], many of these will also have beneficial effects on other aspects of our health too (a win-win in my eyes!) and are appropriate for both athletes and the general population.

1. Practicing good hygiene

While not the flashiest strategy to start with, ensuring optimal self-hygiene practices are in place such as washing hands and covering coughs and sneezes (either with a tissue or in the crease of your arm), is key to limiting both the contact and spread of infection, something that COVID-19 highlighted the importance of. Also, avoiding touching areas of your face, such as eyes, nose and mouth (something we tend to do ~9-23 times per hour!) will help to limit self-inoculation/infection.

FACT: Did you know, a sneeze (and its associated nasal droplets) can travel up to ~7-8 m if not covered and stay in the air for ~10 min!

2. Being Physically active & Exercising (with adequate hydration and clothing)

Physical activity and exercise are powerful tools for helping to maintain our immune health. Following the physical activity (PA) guidelines (at least 150 min of moderate-intensity PA throughout the week, or at least 75 min of vigorous-intensity PA) and exercising regularly have consistently been found to reduce our URTI risk, sometimes by as much as 50%. While it is tempting to hibernate during winter, it is still strongly recommended to stay active. When being physically active or exercising outdoors during winter it is important to stay well hydrated, as the cold dry air can not only reduce our drive for thirst but can quickly dehydrate us through increased sweating and fluid loss, which can also lead to damaged mucosal linings. To prevent this from happening it is important to take a drink with you when exercising and to consider wearing clothing that can cover your nose and mouth. There are some great products on the market that do not restrict airflow when covering the face but aid in warming and humidifying the cold dry winter air before reaching the respiratory tract.

3. Prioritising nutrition

A healthy, balanced diet is one of the most effective ways to support your immune health year-round, but it becomes especially crucial during the winter months. Focus on foods rich in vitamins and minerals that help support immune function. Two of my top picks for supporting immune health during winter are Vitamin D and probiotics – both of which have been shown to reduce your URTI risk.

Vitamin D: Since it’s harder to get enough vitamin D from sunlight during the winter, consider incorporating foods like fatty fish (salmon, mackerel), fortified dairy products, and eggs into your diet. If these foods don’t appeal, you could also look to take a Vitamin D₃ supplement. Taking around 1000-2000 IU a day during winter is typically advised.

Probiotics: Try incorporating fermented foods like yoghurt, kefir, sourdough and kombucha into your diet this winter. If these foods don’t appeal, you could also look to consume probiotics as a supplement instead. There are various drinks, pills, gummies etc. that are available. Try to look for ones that contain at least 1 billion CFU (colony forming units) and the probiotic strains Lactobacillus and Bifidobacterium.

But what happens if you do catch a URTI such as a cold? Is there anything you can do to limit the illness duration and/or severity?

Even while following the above strategies, it is unrealistic to assume we can completely eliminate the risk of illness this winter. So, is there anything we can do if we end up with a URTI such as the common cold?  Thankfully, some of the strategies already discussed (such as probiotic and Vitamin D consumption) can also act to help you better tolerate an illness once infected.

However, are there any over the counter remedies that can help alleviate symptoms of URTI? A recent study I was involved with investigated the use of a commercially available mouth and throat spray (ColdZyme) designed to limit and reduce the symptoms and duration of the common cold. Our group performed both in vivo (monitoring participants over the course of winter to naturally occurring URTI) and in vitro (experimenting on human airway tissue in the lab with rhinovirus) studies using the ColdZyme spray versus a placebo spray ^[4]. The main findings from this work indicate that ColdZyme spray can reduce both the duration and severity of URTI due to reducing viral load (the amount of virus found in a person’s body fluid), likely due to improved integrity of airway tissue lining and causing less cell damage. As such, this handy travel size mouth and throat spray may be a handy addition to your bag this winter.

Winter doesn’t have to be a season of illness. By adopting a few simple strategies — practising good hygiene, staying active and prioritising nutrition, we can winterproof our immune system and limit our chances of illness.

References

1. Keaney et al., 2021. Household illness is the strongest predictor of upper respiratory tract symptom risk in elite rugby union players. Journal of Science and Medicine in Sport, 24(5), 430-434. doi.org/10.1016/j.jsams.2020.10.011

2. Keaney et al., 2022. Upper respiratory tract symptom risk in elite field hockey players during a dry run for the Tokyo Olympics. European Journal of Sport Science, 22(12), 1827-1835. doi.org/10.1080/17461391.2021.2009041

3. Dulson & Keaney. 2023. Endurance training and athlete immune health. In: I. Mujika (Ed.), Endurance Training – Science and practice. Second Edition (pp. 237-248). Vitoria-Gasteiz, Basque Country: Iñigo MujikaS.L.U. ISBN 978-84-939970-4-5.

4. Davison et al., 2025. ColdZyme reduces viral load and upper respiratory tract infection duration and protects airway epithelia from infection with human rhinoviruses. The Journal of Physiology, 603(6), 1483-1501. doi.org/10.1113/JP288136 

By Dr. Yashvee Dunneram

Food has always played a big role in my life. Growing up, I had a close relationship with it — I enjoyed exploring new flavours, helping in the kitchen, and discovering how small changes in preparation could completely transform a meal. As a teenager, I began experimenting in the kitchen myself, and my curiosity quickly evolved into a passion.

Choosing Food and Nutrition at A-level felt like a natural step, followed by a degree in Nutritional Sciences. Throughout my early studies, I was fascinated by the science behind food — how cooking transforms nutrients, how dietary needs evolve throughout life, and how what we eat can influence our health over time. Cooking for me has never just been about taste; it’s about understanding what lies behind every meal.

That curiosity led me to research the complex relationship between diet and cancer risk and survival — a topic that continues to inspire me every day. Diet might seem simple, but it’s one of the most powerful, modifiable factors influencing our long-term health.

Exploring diet and cancer risk

During my time at the University of Oxford as a postdoctoral epidemiologist, I worked on large-scale collaborative studies exploring diet and cancer risk, including the Vegetarian Pooling Project. This international collaboration brings together data from more than two million participants across multiple cohorts worldwide to explore how different dietary patterns — such as vegetarian, pescatarian, and meat-eating — relate to site-specific cancer risk.

Our first publication from this work focused on sociodemographic, lifestyle, and health characteristics of participants with different diet groups across the participating cohorts.¹ The study highlighted substantial variation between diet groups, underlining the importance of considering these factors when examining links between diet and disease. A second paper, examining diet and cancer risk, is currently under review.

Earlier in my career, I also examined the associations between specific foods and the risk of breast, endometrial, and ovarian cancers in the UK Women’s Cohort Study. The research found that higher intakes of processed and total meat were linked with increased cancer risk, while higher intakes of tomatoes and dried fruit were associated with a lower risk.²

My current research at Newcastle

Now, as a Faculty Fellow at Newcastle University, my work focuses on understanding the relationship between diet and colorectal polyps as part of the COLO-COHORT study — an ongoing project aiming to improve the early detection and prevention of colorectal cancer.

Cancer continues to affect millions of people worldwide and can often appear without warning, profoundly impacting individuals and families. This unpredictability reinforces the importance of identifying modifiable factors — such as diet — that could help prevent cancer or improve outcomes after diagnosis.

In recent years, there has also been growing interest in the gut microbiome — the community of microorganisms living in our intestines — and its potential role in cancer development and prevention. What we eat can influence the composition and function of these microbes, which in turn may affect disease risk.

Alongside my current work, I recently co-authored a systematic review examining the relationship between the faecal microbiome and colorectal neoplasia in shotgun metagenomic studies.³ The review highlighted consistent alterations in microbial composition between individuals with colorectal neoplasia and healthy controls, supporting growing evidence that the gut microbiome may play a role in early detection and prevention. This work complements my ongoing research in COLO-COHORT, where we are exploring how dietary factors might interact with the gut microbiome to influence colorectal polyp risk.

I’m also developing grant and fellowship proposals to further explore how diet might influence colorectal cancer survival, an area that remains under-researched but holds great potential for improving patient outcomes. Through this research, I hope to contribute to clearer, evidence-based guidance on how everyday dietary choices can help prevent cancer or improve outcomes after diagnosis.

Away from my desk

Outside of research, I still find joy in food — especially in trying new recipes and sharing meals with friends and family. It’s my creative outlet and a reminder of why I do what I do: because food connects us all, shapes our health, and continues to fascinate me just as much as it did when I first stepped into a kitchen.

References

1. Dunneram, Y. et al. (2024). Methods and participant characteristics in the Cancer Risk in Vegetarians Consortium: a cross-sectional analysis across 11 prospective studies. BMC Public Health, 24(1):2095. https://doi.org/10.1186/s12889-024-19209-y
2. Dunneram, Y. et al. (2019). Diet and risk of breast, endometrial and ovarian cancer: UK Women’s Cohort Study. British Journal of Nutrition, 122(5):564-574. https://doi.org/10.1017/S0007114518003665
3. Manning, S. et al. (2025). Systematic Review: The Relationship Between the Faecal Microbiome and Colorectal Neoplasia in Shotgun Metagenomic Studies. Alimentary pharmacology & therapeutics, 62(6):568-584.  https://doi.org/10.1111/apt.70252

People with Type 1 diabetes (T1D) have a pancreas that no longer secrets enough insulin, so from diagnosis they are dependent on insulin being administered in either an injection or via an insulin pump. This means people must manually balance and adjust their insulin medication according to their meals, while also accounting for what the sugar concentration in the blood is. Unfortunately, life can be a daily battle and tightrope walk to keep their blood sugar in the healthy range and preventing it from going too high (damages blood vessels, eyes, kidneys, nerves), or too low, which can be dangerous for the brain’s energy supply.

Exercise can be a dilemma for people with Type 1 diabetes

In general, people with T1D are encouraged to be physically active due to the associated health benefits (e.g. better heart and lung system), and in general the disease doesn’t hold people back, with thousands running marathons yearly, there is a T1D professional cycling team, there are stars like Henry Slade and Sir Steve Redgrave who reached the pinnacle of their sports (Figure 1). However, for many people exercise is avoided due to worries of their diabetes control deteriorating, or exercise causing dangerously low blood sugar, termed hypoglycaemia (fuel to the brain is compromised). Hypoglycaemia can be fatal if not treated, and the more frequent this event occurs, the more accustomed the body becomes to it and the usual feelings we get when the brains sugar is getting too low (pale, hunger, pins and needles, confusion), don’t occur. This results in a dangerous situation where brain fuel is compromised, but the defence symptoms against it are blunted. Naturally, exercise potentially leading to increased occurrence of hypoglycemia is an understandable barrier.

Figure 1: Type 1 diabetes athletes. Professional cycling team Team Novo Nordisk and England Rugby union international, Henry Slade.

“If I exercise my diabetes gets worse” versus “exercise is no problem for me”

For decades, in clinic observations have reported a wide range in how people cope with frequent exercise with clinicians observing improvements in some and a deterioration of diabetes control in others. Indeed, some clinical colleagues remained sceptical on recommending people engaged in exercise at all, such was the risk that their diabetes control would worsen. Over the past 10 years our group has sought to understand why this is, with the aim that more targeted and personalised support can be created for the individual.

Are the insulin producing cells in the pancreas truly destroyed?

It has been recently shown that while people are dependent on insulin as medication, the pancreas may have an underlying and persistent ability to produce small amounts of insulin still. This is important, because any remaining pancreas function could play a role in how the person walks that tight rope when exercising.

We recently conducted a study where we measured how much ‘C-peptide’ people were secreting in their blood and urine in response to food. C-peptide is released from the pancreas along with insulin and is used to assess how much function or damage is present in the pancreas. We found that in people with established Type 1 diabetes (>5 years), that there was a wide range in how much C-peptide people produced. Some had zero levels of C-peptide, while others had very small amounts and a small fraction of people were still producing a significant amount. We then took these groups of people and got them to walk on an incline treadmill for 45 minutes and monitored their blood sugar for a couple of days after exercise. We found in those with no C-peptide their diabetes control got worse, while in those who were positive, their diabetes control improved. So, despite having the disease similar amounts of time, being of similar fitness, and similar overall diabetes control, a controlled bout of exercise resulted in a divergent split in their blood sugar control; those with C-peptide improving, and those negative, getting worse (1, 2).

Age at diagnosis as an indirect measure of pancreas function

We sought to understand the exercise tightrope further by looking at how the age at someone’s T1D diagnosis might impact their blood sugar control when exercising. Analysing insulin producing cells from pancreas donors shows that the damage in the pancreas seems to be different depending on when they were diagnosed, early childhood versus teenage versus adulthood. We explored how splitting people by these diagnosis-age categories impacted their diabetes control. We showed that those diagnosed before the age of 13 had worse diabetes control when exercising, and those with adulthood diagnosis had better blood sugar when exercising (Figure 2). Put simply, two people of the same fitness, overall diabetes control, and the same duration of diabetes, but one diagnosed as a toddler versus one diagnosed in adulthood, could have divergent changes in their diabetes control when doing the same bout of exercise (3).

Figure 2: Adapted from Taylor et al. (3) – Age at Type 1 diabetes diagnosis versus time in normal blood glucose range.

What does this mean for the exercise tightrope?

We hope our data will provide evidence to clinicians to monitor every person’s C-peptide levels, regardless of how long they have had T1D. This could provide useful information in identifying people at risk of finding exercise hard, it could also mean pushing others to more challenging diabetes control targets. There are also tools like diabetes technology, blood sugar sensors, and exercise education programmes that could be used in a more targeted way to support people to exercise without compromising their diabetes control. At a personal level, people can suffer from a lot of anxiety and distress because of how hard they find managing their diabetes, while others find things easier. If the clinical team are aware that there could be some underlying disease differences that explain this – ultimately, this will improve the persons understanding of their own disease, and potentially make safe exercise, with targeted support, adoptable into the lives of all people with Type 1 diabetes.

References

1. Taylor GS., Shaw, AC., Smith, K., Wason, J., McDonald, TJ., Oram, RA., Stevenson, E., Shaw, JAM., West, DJ. (2020). Capturing the real-world benefit of residual beta-cell function during clinically important time-periods in established type 1 diabetes. Diabetic Medicine, 39:e14814

2. Taylor, GS., Smith, K., Capper, TE., Scragg, JH., Bashir, A., Flatt, A., Stevenson, EJ., McDonald, TJ., Oram, RA., Shaw, JA. & West, DJ. (2020). Post-exercise glycemic control in type 1 diabetes is associated with residual β-cell function. Diabetes Care, 43(10), 2362-2370.
3. Taylor, GS., Bruger, B., Scragg, JH., Page, O., Schmid, H., Nsengimana, J., West, DJ. & Shaw, JA. (2025). Impact of Age at diagnosis and insulin delivery modality on free-living glycemia in Type 1 diabetes during periods associated with dysglycemia: a retrospective analysis of the type 1 diabetes exercise initiative study. Diabetes Technology & Therapeutics, in press.

By Dr. Laura Basterfield

Whilst physical activity has long been promoted as cure for different ailments, our understanding of, and interest in, just how far-reaching those effects are has grown in the last few decades.  One of the benefits of a physically active lifestyle is that at higher intensities it leads to higher physical fitness. Having a fitter heart and lungs means that they can supply your muscles with energy and oxygen more efficiently, so you can keep an activity going for longer. Building stronger muscles also helps strengthen bones, preventing fractures (and making carrying shopping or children easier!). Physical fitness also helps maintain a healthy body composition and reduces the risk of cardiovascular disease and Type 2 diabetes. In addition to the physical benefits, and there is also good evidence suggesting that being physically fit benefits children and young people’s mental wellbeing, too.

What I’m trying to get across is the need not just to increase the amount of physical activity everyone does, but also to make sure that it is enough to increase their fitness.

Sadly we know that globally, children and young people’s physical fitness is in decline, so we need to find innovative ways of encouraging children and young people to get active. Key to this is accessibility – we need to remove any barriers, whether financial, physical, social or geographical  – and offer fun, challenging, varied activities, that children and young people want to join in with.

There are multiple ways to address the problem, including safe active transport, free sports, convenient locations, access to appropriate kit, and exercise sessions at school. High intensity exercise can increase fitness in adolescents, but so far has been led by researchers or teachers. We wanted to increase the sustainability of the programme by using older peers to lead the exercises for younger pupils, which had not previously been tested.

In 2023 I ran a small pilot study to test whether we could train sixth form students (aged 17-18 years) to lead Year 7 pupils (aged 11-12 years) in high intensity exercise sessions, twice a week. We had designed the study with pupils and teachers, to try and offer them what they wanted, and get as many pupils as possible taking part. This wasn’t just for the ‘sporty’ kids – we wanted everyone to join in and feel the benefits. Most children and young people are in school, so this is an easy place for them to take part. The sessions were only 10 minutes long, and took place during morning tutor time. All the exercises could be done in school uniform, and exercises were chosen based on what the pupils said they wanted to do.

Over an afternoon of training with my collaborator Dr Katy Weston (University of Strathclyde) and me, the Young Leaders were taught safe and effective exercises, and how to demonstrate them. They were given a training manual and access to an online site with all the information. For 8 weeks, the five Young Leaders got to know the Year 7 pupils in the group, and led their sessions. The exercises changed from full-body exercises like squat jumps to boxing with sprints, an activity the Year 7s really enjoyed doing.

I was at each of the sessions to support the Young Leaders, and was able to observe the changes in both them and the younger pupils. The confidence and organisational skills of the Young Leaders grew as time went on, and it was great to see the bonds forming between the Year 7s and the Young Leaders. The Year 7s were enthusiastic about joining in each time, and gave it their all. The Young Leaders were dedicated to their role, and tried to involve all the pupils in each session. In addition, we had positive comments from teachers and both sets of pupils, and lots of helpful suggestions on improvements we could make to the training. The benefits to the pupils that were entirely separate from any improvements to their fitness were really encouraging, so we are working on the next version of the programme to test with another group of young people.

We are currently writing up the study for publication (watch this space!), but this is something we will be championing for years to come!

With thanks to my collaborators Dr Katy Weston (University of Strathclyde), Dr Brook Galna (Murdoch University) and Dr Naomi Burn (University of South Australia), and the pupils and teachers at Dukes Secondary School.  

References:

Demchenko, I. et al., (2025).  British Journal of Sports Medicine: bjsports-2024-109184.

Lubans, D. et al., (2021). British Journal of Sports Medicine 55:751-758.

Weston K et al., (2016). PLOS ONE 11(8): e0159116.

By Dr. Anthony Watson

Like any good story, this one starts a long time ago in a land far away. It was in 2011 when I embarked on an industry focussed PhD with Northumbria University and the New Zealand Institute for Plant and Food Research. My memories of my time in New Zealand are very fond but this bog is about science. Since I had the freedom, I thought would write about research many, at least at Newcastle Uni, wont know me for. But it’s a research focus which has been trundling on in the background for a while (my current main projects can be found here).

This research broadly focussed around conducting research to evidence the health benefits of berry fruit, with a specific focus on blackcurrants and their surprising impact on the brain.

It has long been established that blackcurrants contain phytochemicals such as anthocyanins, the compounds which are responsible for their deep purple colour. These compounds have been linked to numerous health benefits, ranging from cardiovascular support to anti-inflammatory effects. But a report by Borman in 1999 outlined that in test tubes, anthocyanins from blackcurrants could inhibit a class of enzymes called monoamine oxidase (MAO). A potential mechanism with potential to be explored (there’s a twist later on).

What is Monoamine Oxidase?

MAO is an enzyme responsible for breaking down key neurotransmitters in the brain, like dopamine, serotonin, and noradrenaline. These chemicals help regulate mood, motivation, and emotional balance. There are two types of MAO A and B.

MAO inhibitors (MAOIs) are a class of drugs historically used to treat depression, anxiety and neurological disorders, because they block this enzyme’s activity, leading to higher levels of these neurotransmitters in the brain. But nonselective and non-reversable inhibition can come with serious side effects and dietary restrictions.

Blackcurrants and MAO Inhibition

As mentioned earlier, there was previous test tube data which showed that anthocyanins from blackcurrants could inhibit MAO. So, we set out to test this in people. A randomised, double-blind, placebo-controlled, crossover study was conducted using 36 healthy young participants. Participants consumed two different blackcurrant extracts (a fresh blackcurrant juice or a commercially available blackcurrant powder fortified with anthocyanins) and a placebo across three separate sessions. The study also aimed to assess the effects on cognitive performance, mood, and circulating neurotransmitters. Participants improved in tasks requiring attention and mental flexibility after consuming blackcurrant extracts when compared to the placebo. Interestingly only the freshly juiced blackcurrant juice and not the anthocyanin fortified powder inhibited MAO. This was a little odd since the original hypothesis was based around anthocyanins, illustrating that compounds other than anthocyanins may be responsible for the observed in vivo MAO inhibition. But, this showed for the first time that the Blackadder variety of blackcurrants (now marketed under the name of Neuroberry) could inhibit both MAO-A and MAO-B in healthy people. The serving size of the juice was about 140ml. You can find the paper here.

I mentioned earlier that there are potentially negative effects of MAO-Is, especially if they are irreversible. For example, hypotensive crisis can occur If someone eats foods high in tyramine (like aged cheeses, cured meats, soy products, red wine, etc.), it can cause a dangerous spike in blood pressure.

Next we set out to assess the pharmacodynamics (time course) of the inhibition to understand if this inhibition is reversible. Just like the first study, we used a double-blind, placebo-controlled, randomised crossover design. Eight healthy male participants consumed a single serving of blackcurrant juice or a placebo. Blood samples were collected at multiple intervals up to 24 hours post-consumption to assess changes in monoamine oxidase activity. The outcome was a fast and absolute inhibition MAO. This was seen from the first measurement at 15 minutes post dose, through to the final day 1 measurement at 4 hours. The inhibition had disappeared by 24 hours. This showed that the inhibition was nonselective, absolute and reversable. Great news! The paper is here and contains some cool effects of blackcurrant on prolactin which may indicate dopamine modulations.

Blackcurrants and Brain activity

I then wanted to understand if blackcurrants were affecting brain activity; the idea was to combine cognitive tests and physiological measurements. Now at Newcastle, I ran a pilot study with nine healthy young adults. The goal was to see if drinking a single serving of blackcurrant juice would acutely brain wave activity in the prefrontal cortex, as measured by electroencephalography (EEG). This time the blackcurrant juice used was made from the UK ‘Ben Hope’ cultivar. Participants visited the lab twice, at least a week apart. On the study days, they arrived fasted, did some baseline tests, drank either the blackcurrant juice or a placebo drink, rested for 45 minutes, and then completed a set of cognitive tasks while their brain waves were recorded. Outcomes of this study were also pretty interesting, an increase delta and theta brain waves was seen after consuming the blackcurrant drink. Changes in these brain waves are an indication of relaxation, suggesting an anxiolytic (anxiety-reducing) effect of the blackcurrant juice. The paper can be found here. My most recent paper which is under review in nutritional neuroscience also showed increases in blood flow in the pre frontal cortex during cognitive demand after consuming blackcurrants. This is potentially mediated by increased neurovascular coupling.

All of this evidence is quite compelling with measurable and repeatable inhibition of MAO, improvements in cognitive performance and effects on brain activity after consumption of New Zealand and UK blackcurrant cultivars. But, there was still the issue of which compound was actually driving the MAO inhibition. The papers which we based the whole research idea on described anthocyanins as the molecule responsible, but our research showed that anthocyanin enriched powders did not have the same effect as a standard juice. Scientists at Plant and Food Research carried on this work and recently found the molecule responsible. It was not anthocyanins but sarmentosin, a glycoside and that is found in several plant species. The paper can be found here.

Back to the original question, “can blackcurrants boost your brain”? Definitely! And there is plenty more great research emerging showing similar results to mine. How much do you need to eat? The studies all focussed on 140ml of Juice, which is about 200g of berries.

What is exiting is the potential application of MAO inhibition in clinical populations, and that will probably be where this line of research goes next.

By Ollie Page (Graduate Teaching Assistant)

Most of us have no immediate health problems consuming a chocolate bar or a pint of beer – sure you might feel guilty, but it’s likely many of us have consumed more than one at a time without worrying. Your average chocolate bar contains ~25g of carbohydrate, with ~15g in a typical pint of beer. To respond, your liver, muscles and adipose (fat) tissue all subdue this influx of glucose all under the watchful protection of a happy pancreas.

However, consider you have type 1 diabetes, and you have no endogenous insulin (that is, the insulin produced by your body) to aid glucose uptake. Or maybe you have type 2 diabetes, and your body resists the insulin being delivered in favour of producing and releasing more fatty acids. The instant and long-term physical, mental, social and occupational health impacts of excess glucose are why it is fundamental to keep an accurate track of your blood glucose using continuous glucose monitors (CGMs).  

But is this technology suitable for the changing environments its users are being exposed to?

People of the UK love a warm summer holiday; however, the sunburn and face fans are becoming increasingly common at home. Climate change has increased average summer temperatures in the UK by 1.3°C in the past 60 years, with maximum temperatures similarly increasing over time and reaching highs of 40.3°C in July 2022. Crucially these temperatures are of high risk to clinical and vulnerable populations, including the elderly and those with diabetes mellitus, as highlighted by a 6.2% rise in excess deaths compared to a 5-year average during the 2022 heat wave (Office for National Statistics, 2022). Due to several physiological factors including impaired hydration and hemodynamics, the rate of core temperature increase and risk of heat-related illness can be higher among people with diabetes and age-associated chronic health conditions than other populations (Meade et al., 2020).

Previous research has calculated an odds ratio of 1.097 per 1°C increase in temperature above 22°C that medical attention will be required (Hajat et al., 2017). In other words, for every 1°C increase in temperature above 22°C, there is an almost 10% increased odds of requiring medical attention. There is a clear heat-related health risk in people with diabetes and hospitals have observed greater inpatients with hypo- or hyperglycaemic events alongside heat stroke or other heat-related illnesses during heat waves (Xu et al., 2019), partly due to increased insulin-independent glucose uptake along with enhanced insulin sensitivity. With this increased risk to health clearly apparent, it is vital CGMs are accurate during hot temperatures.

Leading CGM manufacturers Dexcom and Abbott report maximum operating temperatures of their newest products of 40°C and 45°C, respectively, seemingly within sensible boundaries for heat waves. However, a recent survey by our team has shown 68.4% of recipients have experienced issues with their CGM accuracy and functionality in the heat, with 35.7% unable to take a reading at all (Page et al., 2025. Unpublished). This clearly highlights a key health risk in diabetes populations and the need to adhere for technological failures.

Ultimately, our current work aims to bridge the gaps in understanding of factors affecting CGM accuracy and functionality during different thermal challenges, along with identifying ways to reduce CGM inaccuracy and raise awareness of heat-related risk within people with diabetes.

I’m worried about getting too hot this summer, what can I do??

Cooling strategies are applied in performance and health settings worldwide to avoid heat-related illnesses and reduce core temperature back to safe levels (individual but often below 38°C), however, can be difficult to implement in certain environments or for those with lower socioeconomic status. Strategies can be split into internal and external application depending on their mechanism of action (inside vs outside the body).

Strategies are commonly advertised by health organisations with large variation used, along with adaptation to different settings. According to our recent survey, the most common cooling strategies applied by people with type 1 and type 2 diabetes in the UK are: having a cold drink, using a fan/air conditioning, or having a cold shower/bath (Page et al., 2025. Unpublished). This may be different to your own personal strategies however no strategy that lowers core temperature and reduces cardiovascular stress is wrong and is recommended before, during, and/or after heat exposure.

An extensive list of strategies by world leading experts can be found here published in The Lancet alongside any pros and cons for use (Jay et al., 2021).

https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(21)01209-5/fulltext

References:

Hajat, S., Haines, A., Sarran, C., Sharma, A., Bates, C., & Fleming, L. E. (2017). The effect of ambient temperature on type-2-diabetes: case-crossover analysis of 4+ million GP consultations across England. Environmental health : a global access science source, 16(1), 73. https://doi.org/10.1186/s12940-017-0284-7

Heat Mortality Monitoring Report: 2022. (2024). Office for National Statistics. https://www.gov.uk/government/publications/heat-mortality-monitoring-reports/heat-mortality-monitoring-report-2022

Jay, O., Capon, A., Berry, P., Broderick, C., de Dear, R., Havenith, G., Honda, Y., Kovats, R. S., Ma, W., Malik, A., Morris, N. B., Nybo, L., Seneviratne, S. I., Vanos, J., & Ebi, K. L. (2021). Reducing the health effects of hot weather and heat extremes: from personal cooling strategies to green cities. Lancet (London, England), 398(10301), 709–724. https://doi.org/10.1016/S0140-6736(21)01209-5

Meade, R. D., Akerman, A. P., Notley, S. R., McGinn, R., Poirier, P., Gosselin, P., & Kenny, G. P. (2020). Physiological factors characterizing heat-vulnerable older adults: A narrative review. Environment international, 144, 105909. https://doi.org/10.1016/j.envint.2020.105909

Page, O., Orange, ST., Coussens, A., Dulson, D.K., Jeffries, O. & West D.J. (2025) Perceived Impact of Heat Waves on Daily Health and Management of Type 1 and Type 2 Diabetes Unpublished.

Xu, R., Zhao, Q., Coelho, M. S. Z. S., Saldiva, P. H. N., Zoungas, S., Huxley, R. R., Abramson, M. J., Guo, Y., & Li, S. (2019). Association between Heat Exposure and Hospitalization for Diabetes in Brazil during 2000-2015: A Nationwide Case-Crossover Study. Environmental health perspectives, 127(11), 117005. https://doi.org/10.1289/EHP5688

By Dr. Adrian Holliday

The “obesity epidemic” is a term with which we are all very familiar. However, the prevalence and health consequences of low weight and undernutrition are less well documented and communicated. This is of particular relevance for older adults.

Somewhat paradoxically, we are at an increased risk of both excess weight and low weight as we enter later life. Perhaps surprising to many of us, is that the latter carries the greater risk to health for older adults. In fact, what many would consider as excess weight is protective as we age. A study in the USA followed a cohort of over 4000 over 65s for an average period of 10 years¹. Using World Health Organisation definitions of healthy weight (18.5 – 24.9 km/m²), overweight (25 – 29.9 km/m², and obesity (30 km/m² and above), those in the “overweight” category had a 20% lower risk of all-cause mortality than those in the “healthy weight” category. In fact, those classified as living with obesity were 22% more likely to pass away than those deemed healthy weight. At the other end of the BMI spectrum, those with a BMI of less than 18.5 km/m² were over three-times more likely to pass away than those not classified as underweight. Given that unintentional weight-loss is experienced by 15-20% of older adults, awareness of the health detriments of low weight should be raised.

One reason for older adults having an increased risk of losing weight is a decline in appetite. We may have observed this in loved ones: parents or grandparents who have a small appetite and struggle to eat what we would consider to be a “normal” portion. This age-related reduction in appetite and food intake – termed “anorexia of ageing” – effects approximately 30% of free-living older adults and over half of those in residential care.

Low appetite can be the result of numerous changes experienced in later life. These include the loss of a loved one and loneliness, reductions in physical activity, reductions in smell and taste, and the onset of disease. Recently, our research group has shown that another possible contributing factor is a change in the way our gut senses and responds to the nutrients that we eat. We recruited younger adults and older adults, who we identified as exhibiting either a healthy appetite or low appetite². All participants ate the same porridge breakfast. Before, and for 4 hours after breakfast, we took blood samples to measure the concentration of some appetite-related hormones that are released from the gut in response to feeding. We measured the hunger hormone, ghrelin, and two satiety hormones that signal fullness: PYY and GLP-1. Compared with younger adults, older adults with low appetite had a greater suppression of the hunger hormone ghrelin, while PYY and GLP-1 concentrations increased to a greater extent and stayed elevated for longer. This was not seen in the older adults with healthy appetite, who showed a very similar hormone response to food that was seen in younger people. Consequently, the older adults with low appetite ate less at lunch.

These data suggest that some, but not all, older adults exhibit a degree of hypersensitivity to nutrients, causing an amplified hormone response to cause greater feelings of fullness and suppression of hunger.

Why this occurs in some older adults but not others is not currently known. But, continuing our research in this field, we hope to find out. We suspect that it could be a result of changes in the way the gut digests and absorbs nutrients; changes in the gut environments, such as altered gut microbiome; or changes in the behaviour of the cells which secrete hormones³.

Identifying the cause of this heightened hormone response to feeding may help us design nutritional and pharmaceutical interventions to help appetite-suppressed older adults eat well for health, wellbeing, and longevity in later life.

1. Cheng et al., 2016. Body mass index and all-cause mortality among older adults. Obesity, 24(10), 2232-2239. doi.org/10.1002/oby.21612
2. Dagbasi et al., 2024. Augmented gut hormone response to feeding in older adults exhibiting low appetite. Appetite, 201(3), 107415. doi.org/10.1016/j.appet.2024.107415
3. Dagbasi et al., 2024. The role of nutrient sensing dysregulation in anorexia of ageing: The little we know and the much we don’t. Appetite, 203(6), 107718. doi.org/10.1016/j.appet.2024.107718

Dr. Rachel Stocker

I’m Dr Rachel Stocker and I joined Newcastle University in early 2016, moving to my current lectureship in 2022. As a lecturer in exercise and health psychology, I’m particularly interested in how our thoughts, emotions, and behaviours influence our physical health. My research focuses on helping people engage in various aspects of healthy lifestyles, especially those living with chronic conditions like diabetes.

Breaking down the barriers

For people with chronic illnesses, there are often extra psychological barriers that make it hard to stay active. An example is those living with insulin-treated diabetes. Whilst we know that exercising is good for us, many people with diabetes worry about managing their blood glucose levels during exercise. Resistance training, however, carries less risk of low blood sugar (hypoglycaemia) than aerobic forms of exercise. Resistance training involves working against a force to build strength—think weightlifting, or resistance band exercises. Research shows that resistance exercise is not only safe but also beneficial for managing insulin-treated diabetes.

In fact, resistance training can help stave off sarcopenia—the age-related loss of muscle mass and strength—and frailty, a syndrome that involves decreased physical reserve and increased vulnerability to stressors, which can lead to poor health outcomes. Both conditions are common in older adults, especially in those with insulin-treated diabetes, and contribute significantly to loss of independence. The evidence suggests that regular resistance exercise can slow down the progression of sarcopenia, improving muscle strength and overall physical function. This, in turn, reduces the risk of frailty and helps maintain quality of life.

In my current research, I’m investigating the experiences of older adults with insulin-treated diabetes who are mildly frail, and exploring the psychological and practical challenges they face when engaging in resistance exercise. Using qualitative methods, I’m identifying their fears and barriers to exercising, and also, the strategies they’ve developed to stay active. This work will be important in designing tailored interventions that encourage more people to take up resistance training, ultimately improving health and reducing frailty in this population.

Other research projects

As a chartered psychologist specialising in health psychology, I really enjoy applying health psychology and behaviour science principles in different settings and disease/illnesses. Alongside my work in diabetes, I’m involved in some exciting projects that look at other health issues. One of these explores the experiences of patients using the NHS specialist Chimeric Antigen Receptor (CAR) T-cell therapy service, focusing on their psychosocial and supportive care needs and how to address them. Another project is about increasing physical activity to reduce dementia risk in ethnically minoritised communities in the North East of England, by working together to create interventions that really fit their needs.

Supporting future health researchers

Another part of my work that I’m passionate about is supervising PhD students. For example, Ayat Bashir is working on improving the diagnosis and management of diabetes secondary to chronic pancreatitis. Keaton Irvine is researching how to improve health for individuals with type 2 diabetes from historically underrepresented groups. Blossom Bell is exploring the long-term care experiences of haematopoietic stem cell recipients, and Evridiki Iliaki is studying how museum experiences can promote mindfulness and social unity in the Middle East.

Looking ahead

Ultimately, my aim is to make healthy lifestyles more accessible for everyone, particularly for those living with chronic health conditions. By understanding the psychological factors that affect exercise and dietary behaviour, we can design strategies that don’t just improve physical health but also have a positive impact on mental wellbeing and quality of life.

By Dr. Changhyun Lim

As many of you know, lifting heavier weights is the most effective method for muscle hypertrophy. I completely agree with this. However, if you’re asking whether lifting heavy weights is the only way to induce muscle growth, my answer is clearly NO.

The practice of lifting heavier weights (70-80% of your 1 rep max or maximal effort) for muscle growth originally came from the bodybuilding community. Interestingly, this approach wasn’t based on scientific research at first, but rather on the undeniable visual proof — the massive muscle mass of bodybuilders. This was so persuasive that most exercise prescription textbooks have long recommended heavy weight lifting for hypertrophy. However, this can sometimes become a barrier to initiating exercise for the first or increase the risk of injury, especially for individuals who may be physically frail, ill, ageing, or simply uncomfortable lifting heavy weights.

Thankfully, research, including my own study, has shown that lifting lighter weights (30% 1RM) can result in similar muscle growth to higher weights, as long as the sets are performed to near failure [1-3]. In other words, whether you’re lifting heavy or light weights, muscle hypertrophy can be achieved as long as you push your muscles close to fatigue (you don’t need to reach complete failure but close to it).  

So, how does this work? When you lift weights, your body recruits motor units — bundles of muscle fibres controlled by a nerve — to contract the muscle. As you continue lifting closer to fatigue, some motor units get tired, and your body has to recruit additional motor units to maintain the effort. Eventually, all available motor units (i.e., muscle fibres) are recruited [4], triggering the cellular and molecular mechanisms responsible for protein synthesis [5].

In line with this, my previous study demonstrated that lighter-weight resistance training effectively recruits type II fibres (those typically activated during higher-force contractions, such as with heavier weight lifting) [1]. This was evidenced by the increase in the cross-sectional area of both type I and II muscle fibres. Additionally, and surprisingly, lighter-weight training with higher repetitions (to reach near fatigue) showed significantly improved mitochondrial function ¾ an effect usually associated with aerobic exercise, not heavy-weight training.

This doesn’t mean there’s anything wrong with lifting heavy for muscle growth. However, it’s important to know that there are more choices available for muscle hypertrophy, such as lighter-weight training. The lighter-weight training can be safer, reduce barriers to participation, and offer similar results. Lastly, while more research is needed, lighter weight training may even provide the added bonus of improving aerobic adaptations while building muscle mass— essentially, “kill two birds with one stone.”

References

1. Lim C, Kim HJ, Morton RW, Harris R, Phillips SM, Jeong TS, et al. Resistance Exercise-induced Changes in Muscle Phenotype Are Load Dependent. Med Sci Sports Exerc. 2019;51:2578-85. doi:10.1249/MSS.0000000000002088

2. Carvalho L, Junior RM, Barreira J, Schoenfeld BJ, Orazem J, Barroso R. Muscle hypertrophy and strength gains after resistance training with different volume-matched loads: a systematic review and meta-analysis. Appl Physiol Nutr Metab. 2022;47:357-68. doi:10.1139/apnm-2021-0515

3. Schoenfeld BJ, Grgic J, Ogborn D, Krieger JW. Strength and Hypertrophy Adaptations Between Low- vs. High-Load Resistance Training: A Systematic Review and Meta-analysis. J Strength Cond Res. 2017;31:3508-23. doi:10.1519/JSC.0000000000002200

4. Morton RW, Sonne MW, Farias Zuniga A, Mohammad IYZ, Jones A, McGlory C, et al. Muscle fibre activation is unaffected by load and repetition duration when resistance exercise is performed to task failure. J Physiol. 2019;597:4601-13. doi:10.1113/JP278056

5. Lim C, Nunes EA, Currier BS, McLeod JC, Thomas ACQ, Phillips SM. An Evidence-Based Narrative Review of Mechanisms of Resistance Exercise-Induced Human Skeletal Muscle Hypertrophy. Med Sci Sports Exerc. 2022;54:1546-59. doi:10.1249/MSS.0000000000002929