As our global population is projected to live longer than ever before, it’s important that we find ways of helping people live healthier for longer. Exercise and diet are often cited as the best ways of maintaining good health well into our twilight years. But recently, research has also started to look at the role our gut – specifically our microbiome – plays in how we age.
Our latest study has found that eating a Mediterranean diet causes microbiome changes linked to improvements in cognitive function and memory, immunity and bone strength.
The gut microbiome is a complex community of trillions of microbes that live semi-permanently in the intestines. These microbes have co-evolved with humans and other animals to break down dietary ingredients such as inulin, arabinoxylan and resistant starch, that the person can’t digest. They also help prevent disease-causing bacteria from growing.
However, the gut microbiome is extremely sensitive, and many things including diet, the medications you take, your genetics, and even conditions like inflammatory bowel disease and irritable bowel syndrome, can all change the gut microbiota community. The gut microbiota plays a such a huge role in our body, it’s even linked to behavioural changes, including anxiety and depression. But as for other microbiome-related diseases such as type 2 diabetes and obesity, changes in the microbiome are only part of the issue – the person’s genetics and bad lifestyle are major contributing factors.
Since our everyday diets have such a big affect on the gut microbiome, our team was curious to see if it can be used to promote healthy ageing. We looked at a total of 612 people aged 65-79, from the UK, France, the Netherlands, Italy and Poland. We asked half of them to change their normal diet to a Mediterranean diet for a full year. This involved eating more vegetables, legumes, fruits, nuts, olive oil and fish, and eating less red meat, dairy products and saturated fats. The other half of participants stuck to their usual diet.
Mediterranean microbiome
We initially found that those who followed the Mediterranean diet had better cognitive function and memory, less inflammation, and better bone strength. However, what we really wanted to know was whether or not the microbiome was involved in these changes.
Interestingly, but not surprisingly, a person’s baseline microbiome (the species and number of microbes they had living in their gut before the study started) varied by country. This baseline microbiome is likely a reflection of the diet they usually ate, alongside where they lived. We found that participants who followed the Mediterranean diet had a small but insignificant change in their microbiome diversity – meaning there was only a slight increase in the overall number and variety of species present.
However, when we compared how strictly a person followed the diet with their baseline microbiome data and their microbiome after following the diet, we were able to identify two different gut microbe groups: diet-positive microbes that increased on the Mediterranean diet, and diet-negative microbes whose abundance was reduced while following the diet.
Diet-positive microbes are microbes that flourished in the Mediterranean diet. Diet-negative microbes either couldn’t metabolise the diet, or they were were unable to compete with diet-positive microbes. These diet-positive microbes were linked with less frailty and inflammation in the body, and higher levels of cognitive function. Losing the diet-negative microbes was also associated with the same health improvements.
When we compared the changes in the number of these microbes in the treatment group (those on the Mediterranean diet) and the control group (those following their regular diet), we saw that the people who strictly followed the Mediterranean diet increased these diet-positive microbes. Although the changes were small, these finding were consistent across all five countries – and small changes in one year can make for big effects in the longer term.
Many of the participants were also pre-frail (meaning their bone strength and density would start decreasing) at the beginning of the study. We found the group who followed their regular diet became frailer over the course of the one-year study. However, those that followed the Mediterranean diet were less frail.
The link between frailty, inflammation, and cognitive function, to changes in the microbiome was stronger than the link between these measures and dietary changes. This suggests that the diet alone wasn’t enough to improve these three markers. Rather, the microbiome had to change too – and the diet caused these changes to the microbiome.
These types of studies are challenging and expensive, and the microbiome dataset is often difficult to analyse because there are many more data-points to study than there are people in the study. Our findings here were possible because of the large group sizes, and the length of the intervention.
However, we recognise that following a Mediterranean diet isn’t necessarily doable for everybody who starts thinking about ageing, usually around the age of 50. Future studies will need to focus on what key ingredients in a Mediterranean diet were responsible for these positive microbiome changes. But in the meantime, it’s clear that the more you can stick to a Mediterranean diet, the higher your levels of good bacteria linked to healthy ageing will be.
This article is part of a series tied to Medicine made for you, a series by The Anthill podcast on the future of healthcare and how it could soon get a lot more personal. Read more here.
The Canadian government says it will donate up to 200,000 vaccine doses to fight the mpox outbreak in Congo and other African countries.
It says the donated doses of Imvamune will come from Canada’s existing supply and will not affect the country’s preparedness for mpox cases in this country.
Minister of Health Mark Holland says the donation “will help to protect those in the most affected regions of Africa and will help prevent further spread of the virus.”
Dr. Madhukar Pai, Canada research chair in epidemiology and global health, says although the donation is welcome, it is a very small portion of the estimated 10 million vaccine doses needed to control the outbreak.
Vaccine donations from wealthier countries have only recently started arriving in Africa, almost a month after the World Health Organization declared the mpox outbreak a public health emergency of international concern.
A few days after the declaration in August, Global Affairs Canada announced a contribution of $1 million for mpox surveillance, diagnostic tools, research and community awareness in Africa.
On Thursday, the Africa Centres for Disease Control and Prevention said mpox is still on the rise and that testing rates are “insufficient” across the continent.
Jason Kindrachuk, Canada research chair in emerging viruses at the University of Manitoba, said donating vaccines, in addition to supporting surveillance and diagnostic tests, is “massively important.”
But Kindrachuk, who has worked on the ground in Congo during the epidemic, also said that the international response to the mpox outbreak is “better late than never (but) better never late.”
“It would have been fantastic for us globally to not be in this position by having provided doses a much, much longer time prior than when we are,” he said, noting that the outbreak of clade I mpox in Congo started in early 2023.
Clade II mpox, endemic in regions of West Africa, came to the world’s attention even earlier — in 2022 — as that strain of virus spread to other countries, including Canada.
Two doses are recommended for mpox vaccination, so the donation may only benefit 100,000 people, Pai said.
Pai questioned whether Canada is contributing enough, as the federal government hasn’t said what percentage of its mpox vaccine stockpile it is donating.
“Small donations are simply not going to help end this crisis. We need to show greater solidarity and support,” he said in an email.
“That is the biggest lesson from the COVID-19 pandemic — our collective safety is tied with that of other nations.”
This report by The Canadian Press was first published Sept. 13, 2024.
Canadian Press health coverage receives support through a partnership with the Canadian Medical Association. CP is solely responsible for this content.
HALIFAX – The Nova Scotia government says it could be months before it reveals how many people are on the wait-list for a family doctor.
The head of the province’s health authority told reporters Wednesday that the government won’t release updated data until the 160,000 people who were on the wait-list in June are contacted to verify whether they still need primary care.
Karen Oldfield said Nova Scotia Health is working on validating the primary care wait-list data before posting new numbers, and that work may take a matter of months. The most recent public wait-list figures are from June 1, when 160,234 people, or about 16 per cent of the population, were on it.
“It’s going to take time to make 160,000 calls,” Oldfield said. “We are not talking weeks, we are talking months.”
The interim CEO and president of Nova Scotia Health said people on the list are being asked where they live, whether they still need a family doctor, and to give an update on their health.
A spokesperson with the province’s Health Department says the government and its health authority are “working hard” to turn the wait-list registry into a useful tool, adding that the data will be shared once it is validated.
Nova Scotia’s NDP are calling on Premier Tim Houston to immediately release statistics on how many people are looking for a family doctor. On Tuesday, the NDP introduced a bill that would require the health minister to make the number public every month.
“It is unacceptable for the list to be more than three months out of date,” NDP Leader Claudia Chender said Tuesday.
Chender said releasing this data regularly is vital so Nova Scotians can track the government’s progress on its main 2021 campaign promise: fixing health care.
The number of people in need of a family doctor has more than doubled between the 2021 summer election campaign and June 2024. Since September 2021 about 300 doctors have been added to the provincial health system, the Health Department said.
“We’ll know if Tim Houston is keeping his 2021 election promise to fix health care when Nova Scotians are attached to primary care,” Chender said.
This report by The Canadian Press was first published Sept. 11, 2024.
ST. JOHN’S, N.L. – Newfoundland and Labrador‘s chief medical officer is monitoring the rise of whooping cough infections across the province as cases of the highly contagious disease continue to grow across Canada.
Dr. Janice Fitzgerald says that so far this year, the province has recorded 230 confirmed cases of the vaccine-preventable respiratory tract infection, also known as pertussis.
Late last month, Quebec reported more than 11,000 cases during the same time period, while Ontario counted 470 cases, well above the five-year average of 98. In Quebec, the majority of patients are between the ages of 10 and 14.
Meanwhile, New Brunswick has declared a whooping cough outbreak across the province. A total of 141 cases were reported by last month, exceeding the five-year average of 34.
The disease can lead to severe complications among vulnerable populations including infants, who are at the highest risk of suffering from complications like pneumonia and seizures. Symptoms may start with a runny nose, mild fever and cough, then progress to severe coughing accompanied by a distinctive “whooping” sound during inhalation.
“The public, especially pregnant people and those in close contact with infants, are encouraged to be aware of symptoms related to pertussis and to ensure vaccinations are up to date,” Newfoundland and Labrador’s Health Department said in a statement.
Whooping cough can be treated with antibiotics, but vaccination is the most effective way to control the spread of the disease. As a result, the province has expanded immunization efforts this school year. While booster doses are already offered in Grade 9, the vaccine is now being offered to Grade 8 students as well.
Public health officials say whooping cough is a cyclical disease that increases every two to five or six years.
Meanwhile, New Brunswick’s acting chief medical officer of health expects the current case count to get worse before tapering off.
A rise in whooping cough cases has also been reported in the United States and elsewhere. The Pan American Health Organization issued an alert in July encouraging countries to ramp up their surveillance and vaccination coverage.
This report by The Canadian Press was first published Sept. 10, 2024.
