A key molecule produced by gut bacteria is linked to less belly fat, according to the latest TwinsUK research.
The team found that gut bacteria play an important role in determining the levels of the molecule acetate in the blood, in the largest study to date of its kind.
Belly fat – also known as visceral fat – puts individuals at greater risk of conditions such as heart disease and type 2 diabetes. The findings open the door to targeted treatments in the future to reduce belly fat via changes in gut bacteria.
First author and PhD student Ana Nogal explained:
“We know from previous research that acetate produced by gut bacteria is linked to lower risk of conditions such as heart disease. Our research now shows that this might be because acetate could reduce belly fat levels.”
The team analysed the associations between blood acetate levels, gut bacteria communities and visceral fat in 948 TwinsUK members. Twins who had more diverse gut bacteria had greater levels of acetate and lower levels of visceral fat.
The researchers also identified two specific groups of bacteria that had the largest positive and negative effect on acetate levels.
As this study only looked at women, further research is needed to understand if gut bacteria and acetate have the same effect on belly fat in men.
Senior author Dr Cristina Menni said:
“Thank you very much to our TwinsUK members for donating blood and stool samples and having DEXA scans during your clinic visits. Your contributions over the years have enabled us to learn so much about the microbiome and how it impacts health.”
The project, called the Alleviate Hub, will bring together chronic pain data into one place.
Researchers will be able to apply to use this data to help address complex questions about chronic pain, diagnosis, treatment and, to ultimately, improve the physical and mental wellbeing of those living with chronic pain.
TwinsUK scientist and pain researcher Professor Frances Williams is a co-investigator on this project, which is led by the University of Dundee.
The challenge
Chronic pain is a major unmet global public health challenge that causes significant disability through conditions such as fibromyalgia, back pain, headaches and migraines.
It is also a debilitating feature of long-term conditions including arthritis, cancer and dementia.
To help address this challenge and improve the lives of people affected by pain conditions, better understanding of the mechanisms of pain and improved treatments are needed.
The project
The Alleviate Hub will maximise the value of chronic pain data from diverse sources, making the data Findable, Accessible, Interoperable and Reusable (‘FAIR’) for researchers and innovators to discover and request access to via the Health Data Research Innovation Gateway – a common entry point to discover and request access to an array of UK health-related datasets.
The team of researchers will deliver world class health data infrastructure and services for pain research, guided by leading experts in pain research and in partnership with the NHS, Advanced Pain Discovery Platform consortia, people with lived experience of chronic pain, and industry.
Professor Frances Williams said:
“Chronic pain has a major impact on quality of life, and the condition is currently very challenging to treat. We hope that by making chronic pain data available in one place, we will be able to accelerate research into the condition and enable the development of effective treatments sooner for patients.”
Taking
multivitamins, omega-3, probiotics or vitamin D supplements may lessen the risk
of testing positive for COVID-19 for women, according to recent findings from
the COVID Symptom Study app.
“There has been plenty of celebrity endorsement of the use of dietary supplements to both ward off and treat COVID-19 infection since the start of the pandemic, although scientific evidence has been lacking.
“Our research shows that women taking certain supplements were slightly less likely to test positive for COVID-19, but we need further research to understand why this is the case before we can recommend these supplements to all women to protect against COVID-19.”
In the UK alone,
sales of vitamin C rose by 110% and those of multivitamins by 93% in the period
leading up to the first lockdown in March 2020.
The researchers analysed
information supplied by 372,720 adult users of the COVID-19 Symptom Study app
to see if regular supplement users were less likely to test positive for
SARS-CoV-2, the virus responsible for COVID-19 infection.
The app was
launched in the UK in March 2020 to capture self-reported information on
symptoms, test results and other health and lifestyle information throughout the
pandemic.
Taking probiotics,
omega-3 fatty acids, multivitamins or vitamin D was associated with a lower
risk of COVID-19 infection by 14%, 12%, 13% and 9% respectively, even after
accounting for other factors such as underlying conditions and the overall
quality of each person’s diet. In addition, the team found that these
supplements had a slight protective effect for women of all ages and weights.
No such effects were
observed among men or in those taking vitamin C, zinc or garlic
supplements.
Senior
author Cristina Menni said:
“This study indicates there may be a link between supplements and COVID-19, but our research is an observational study and not a clinical trial. We need further research and clinical trials to establish if taking certain supplements can indeed offer any protection against COVID-19.
Professor Tim Spector said:
“Many people think that taking vitamins and other supplements can help maintain a healthy immune system but spending your money on supplements in the hope of trying to avoid getting COVID-19 is largely unjustified. You’re better off focusing on getting a healthy diet with diverse fresh vegetables and fruits, which should give you all the nutrients you need for a healthy immune system.
“Until we have further evidence about the role of supplements in COVID prevention, we recommend following NHS guidance on vitamins usage, as part of a healthy balanced diet.”
People who experience big dips in blood sugar levels several
hours after eating end up feeling hungrier and consuming hundreds more calories
during the day than others, according to the latest findings from the PREDICT
study.
The results, published in Nature Metabolism, explain why some people struggle to lose weight, even on calorie-controlled diets, and highlight the importance of understanding personal metabolism when it comes to diet and health.
Dr Sarah Berry from King’s College London said:
“It has long been suspected that blood sugar levels play an important role in controlling hunger, but the results from previous studies have been inconclusive. We’ve now shown that sugar dips are a better predictor of hunger and subsequent calorie intake than the initial blood sugar peak response after eating, changing how we think about the relationship between blood sugar levels and the food we eat.”
The research
PREDICT is the largest ongoing nutritional research programme
in the world that looks at responses to food in real life settings.
The research team collected detailed data about blood sugar
responses and other markers of health from 1,070 people after eating standardised
breakfasts and freely chosen meals over a two-week period, adding up to more
than 8,000 breakfasts and 70,000 meals in total.
Participants wore stick-on continuous glucose monitors
(CGMs) to measure their blood sugar levels over the entire duration of the
study. They also recorded levels of hunger and alertness using a phone app,
along with exactly when and what they ate over the day.
Previous studies looking at blood sugar after eating have
focused on the way that levels rise and fall in the first two hours after a
meal, known as a blood sugar peak. After analysing the data however, the
PREDICT team noticed that some people experienced significant ‘sugar dips’ 2-4
hours after this initial peak, where their blood sugar levels fell rapidly
below baseline before coming back up.
Big dippers had a 9% increase in hunger, and waited around
half an hour less, on average, before their next meal than little dippers, even
though they ate exactly the same meals.
Big dippers also ate 75 more calories in the 3-4 hours after
breakfast and around 312 calories more over the whole day than little dippers.
This kind of pattern could potentially turn into 20 pounds of weight gain over
a year.
Professor Ana Valdes from the School of Medicine at the
University of Nottingham, who led the study team, said:
“Many people struggle to lose weight and keep it off, and just a few hundred extra calories every day can add up to several pounds of weight gain over a year. Our discovery that the size of sugar dips after eating has such a big impact on hunger and appetite has great potential for helping people understand and control their weight and long-term health.”
Everyone is different
Comparing what happens when participants eat the same test
meals revealed large variations in blood sugar responses between people. The
researchers also found no correlation between age, bodyweight or BMI and being
a big or little dipper, although males had slightly larger dips than females on
average.
There was also some variability in the size of the dips
experienced by each person in response to eating the same meals on different days,
suggesting that whether you’re a dipper or not depends on individual
differences in metabolism, as well as the day-to-day effects of meal choices
and activity levels.
Tim Spector, Professor of Genetic Epidemiology at King’s
College London and scientific co-founder of ZOE, concluded:
“Food is complex and humans are complicated, but our research is finally starting to open up the black box between diet and health. We’re excited to have been able to turn this cutting-edge science into an at-home nutrition and microbiome test so that everyone has the opportunity to discover their unique responses to food to best support their metabolism and gut health.”
The immune system of quitters is almost completely restored to a healthy state, according to the latest research from TwinsUK in collaboration with the Italian Institute for Genomic Medicine and the University of Turin.
Smoking kills more than 8 million
people every year across the world and is linked to a range of diseases,
including several types of cancer.
This study is the first to show the
effect of smoking on specific cell types, building on previous evidence that
smoking impacts the overall levels of key immune system cells.
First author Giulia Piaggeschi from the Italian Institute
for Genomic Medicine and the University of Turin said:
“We’ve known for a long time that smoking is bad for your health. The good news from this study, however, is that by stopping smoking, your immune system cells are almost completely restored back to normal.”
The team carried out a detailed analysis of the immune system cells in 358 healthy women from TwinsUK, some of whom were smokers while others had never smoked or were ex-smokers.
The researchers found that smokers had lower levels of
certain protective immune cells and higher levels of immune cells that cause
chronic inflammation.
Individuals who had quit smoking however had immune cells
levels back to normal, with the exception of only two specific types which
remained altered.
On the findings, senior author Dr Alessia Visconti from
TwinsUK, King’s College London, said:
“We now need further research to understand how these changes in immune cells may be linked with smoking- and immune-related diseases such as cancer and autoimmune conditions.”
The genetics
of human eye colour is much more complex than previously thought, according to a
new study published today.
An international team of researchers led by King’s College London and Erasmus University Medical Center Rotterdam have identified 50 new, previously unknown genes for eye colour in the largest genetic study of its kind to date. The study, published in Science Advances, involved the genetic analysis of almost 195,000 people across Europe and Asia.
These
findings will help to improve our understanding of eye diseases such as pigmentary
glaucoma and ocular albinism, where eye pigment levels play a role.
In addition,
the team found that eye colour in Asians with different shades of brown is
genetically similar to eye colour in Europeans ranging from dark brown to light
blue.
This study
builds on previous research in which scientists had identified a dozen genes
linked to eye colour, believing there to be many more. Historically, scientists
thought that variation in eye colour was controlled by one or two genes only, with
brown eyes dominant over blue eyes.
Co-senior
author Dr Pirro Hysi, King’s College London, said:
“These findings are exciting because they bring us to a step closer to predicting with a high degree of confidence the colour of the eyes based on DNA information alone. In certain circumstances, that could allow parents to predict the eye colour of their future children, based on the parents’ genetics. But these findings will also be important and tremendously improve our understanding of many diseases that we know are associated with specific pigmentation levels.”
Co-senior
author Dr Manfred Kayser, Erasmus University Medical Center Rotterdam, said:
“Amongst other relevancies, this study delivers the genetic knowledge needed to improve eye colour prediction from DNA as already applied in anthropological and forensic studies, but with limited accuracy for the non-brown and non-blue eye colours.”
TwinsUK will be joining forces with other cohort studies across the UK to study Long COVID through a key project announced last week.
Approximately one in 10 people with COVID-19 continue to experience symptoms and impaired quality of life beyond 12 weeks, known as Long COVID.
The project, which
has received £9.6 million in funding from UKRI over three years, aims to
provide an evidence base for healthcare services to define what Long COVID is
and improve diagnosis. The project will address why some people get the
condition; the typical effects on a person’s health and ability to work; and
the factors which affect recovery.
Dr Claire Steves, Deputy Clinical Director of TwinsUK, will be leading TwinsUK’s contribution to the project. Dr Steves said:
“I am thrilled that TwinsUK will be involved in this national effort to study Long COVID and its long-term effects. This research is essential so that we can understand how healthcare services can best support people experiencing Long COVID.”
Long COVID can present with clusters of symptoms that are often overlapping and/or fluctuating. Symptoms vary, but common ones include breathlessness, headaches, cough, fatigue, cognitive impairment or ‘brain fog’. Long COVID may comprise several distinct syndromes not yet fully understood and these studies will help solve this.
Over the three years of the project, the team of researchers
will use data from more than 60,000 people drawn from a combination of anonymised
health records and longitudinal studies of people of all ages across the
country (like TwinsUK).
From these studies, people reporting Long COVID and comparator
groups will be asked to wear a wrist band measuring exercise ability, breathing
and heart rate. Participants will also complete online questionnaires on mental
health and cognitive function. They may also be invited to a clinic for
non-invasive imaging to look at potential damage to vital organs, such as the
brain, lungs and heart.
Dr Claire Steves said:
“Throughout the pandemic, our twins have taken part in a variety of essential studies to understand COVID-19. I am grateful for and humbled by their commitment to health research, a feeling which I know is shared by everyone at TwinsUK.”
Over-60s with a good appetite have more diverse and different
communities of microbes in their gut than those with a poor appetite, according
to a new study from King’s College London and the University of Southampton.
In addition, the researchers found that lower appetite was associated
with reduced muscle strength and function, with gut bacteria as a potential
link between the two.
Co-first author Dr Ruth Bowyer, Research Associate at TwinsUK,
King’s College London, said:
“Loss of appetite is very common in older people, and this can have serious consequences including loss of muscle mass and function. Our research is the first to explore the links between appetite and gut bacteria, and how this may be related to muscle strength.”
The team used appetite questionnaire answers to identify 102
twins who had small appetites and 102 twins who had greater appetites, and
compared their gut bacteria. The two groups of twins were otherwise as similar
as possible in terms of age, body mass index, calorie consumption, antibiotic
use and other factors that could impact gut bacteria.
The researchers found that twins with a poor appetite had
less variety in their gut bacteria than twins with a good appetite. They also
found that twins with healthy appetites were more likely to have microbes
associated with diets high in vegetables and fibre.
The team then looked at participants’ muscle strength, based
on previous muscle strength assessments completed during clinic visits, and
found that twins with a lower appetite had reduced muscle strength compared to
twins with a good appetite.
Co-first author Dr Natalie Cox, Clinical Research Fellow at
the University of Southampton, explained:
“A lower appetite can lead to undernutrition, which in turn can lead to loss of muscle mass and so reduced muscle strength. We know from previous research however that a poor appetite is also linked to loss of muscle strength independent of overall weight loss.
“We now need studies to understand how exactly appetite, gut bacteria and muscle function affect each other and in what order. This could inform the development of treatments in the future to preserve muscle mass and function, to improve health in older age.”
“We know from previous twin studies that there is a strong genetic component for specific foods such as coffee and garlic, as well as overall eating habits. Our latest study is the first to show that food and nutrient intake, as measured by nine dietary indices, is also partly under genetic control.”
Researchers can study the quality of an individual’s typical
diet by using a type of analysis called ‘dietary indices’. Researchers use
dietary indices to understand what foods someone eats and the nutrients
provided, compared with recommended guidelines.
The team analysed food questionnaire responses from 2,590
TwinsUK members, using nine commonly used dietary indices. The researchers studied the degree of
similarity among identical twins – who share 100% of their genes – compared
with non-identical twins, who share 50% of their genes.
The team found that identical twin pairs were more likely to
have similar scores across nine dietary indices compared with non-identical
twin pairs. This was the case even when other factors were taken into account,
such as body mass index (BMI) and exercise levels. The results indicate that
there is a genetic component to food intake patterns.
Senior author Dr Massimo Mangino said:
“Our study represents the first comprehensive investigation of the contributions of genetic and environmental factors to the variation in eating behaviour. It highlights the complex relationship between genetic and environment and may have future implications for public health nutrition campaigns.
“This study used food data from female twins only, with an average age of 58. Future research will need to look at dietary indices across a more varied group of people to see if the same findings hold true.”
The latest PREDICT results have uncovered 15 gut microbes
associated with lower risks and 15 with greater risks for common conditions such
as type 2 diabetes and heart disease.
The team of researchers studied thousands of stool samples
and found evidence that an individual’s microbiome is linked to the specific
foods they eat. Furthermore, certain microbes in the gut are linked to biomarkers
of metabolic disease, and the microbiome has a greater association to these
markers than other factors, such as genetics.
The research, which identified novel microbes that have not
yet been named, could be used to provide personalised dietary advice for
improved health.
Professor Tim Spector, who started the PREDICT study programme
and is scientific founder of healthcare science company ZOE explains:
“When you eat, you’re not just nourishing your body, you’re feeding the trillions of microbes that live inside your gut.”
The PREDICT 1 study analysed detailed data on the composition of 1,100 participants’ gut microbiomes, their dietary habits and cardiometabolic blood biomarkers. 660 of our TwinsUK members took part in this study.
For example, the findings reveal that having a microbiome rich in Prevotella copri and Blastocystis species was associated with maintaining a favourable blood sugar level after a meal. Other species such as Eubacterium eligens and Roseburia sp. CAG:182 were linked to lower post-meal levels of blood fats and markers of inflammation.
Overall, the team found that diets rich in certain plant-based foods and healthy animal-based foods (e.g. oily fish, eggs and yogurt) were linked with the presence of “good” gut microbes that are associated with a lower risk of developing conditions such as obesity, type 2 diabetes and heart disease.
Conversely, diets containing more highly processed
plant-based foods were more likely to be associated with “bad” gut microbes, as
were diets containing less healthy animal-based foods.
This is the largest and most detailed study of its kind to uncover
strong links between a person’s diet, the gut microbiome and their health, and these
findings highlight the importance of food quality.
Dr Sarah Berry, from the Department of Nutritional Sciences
at King’s College London said:
“As a nutritional scientist, finding novel microbes that are linked to specific foods, as well as metabolic health, is exciting. Given the highly personalised composition of each individuals’ microbiome, our research suggests that we may be able to modify our gut microbiome to optimise our health by choosing the best foods for our unique biology.”
Looking ahead
Professor Nicola Segata from the University of Trento,
Italy, led the microbiome analysis. Of the findings and future research, he
said:
“We were surprised to see such large, clear groups of what we informally call ‘good’ and ‘bad’ microbes emerging from our analysis.
“It is also exciting to see that microbiologists know so little about many of these microbes that they are not even named yet. This is now a big area of focus for us, as we believe they may open new insights in the future into how we could use the gut microbiome as a modifiable target to improve human metabolism and health.”
