No man is an island, they say. But even the biggest recluses among us are never alone – we are all, in fact, outnumbered. From the moment we are born, our bodies are colonised by other organisms – a vast population of microbes setting up home on our skin, inside our mouths and noses, and in our gut. So much so that only 10 per cent of the cells in our body are human cells.
It should come as no surprise then, that how our bodies work is less of a dictatorship and more of a democracy. All the bacteria living within our body have to co-operate to help things run smoothly and prevent civil war. This isn't for free, of course. We feed the hungry little buggers – and in return they help to break down our food and convert it to energy, provide essential enzymes and vitamins, and regulate our immune system. The problems arise when the wrong kind of food helps the troublemakers to flourish at the expense of our healthy, helpful "good bacteria".
So far, so yoghurt commercial. But scientists now say that the microbiome – the collected microorganisms – in our digestive system is more than a mulching factory for food, but in fact the "second brain" – which may be just as important as the first brain in our heads. Perhaps we already know this to some extent – we associate the gut with raw, instinctive emotions and reactions. Gut reactions, even. We know that if we're stressed or anxious, this will be the first place we show symptoms of it, which makes sense. In times of fight or flight, the body will shut down its energy-sapping digestive processes to allow the energy to be diverted elsewhere.
Health news in pictures
Health news in pictures
1/25 Most child antidepressants are ineffective and can lead to suicidal thoughts
The majority of antidepressants are ineffective and may be unsafe, for children and teenager with major depression, experts have warned. In what is the most comprehensive comparison of 14 commonly prescribed antidepressant drugs to date, researchers found that only one brand was more effective at relieving symptoms of depression than a placebo. Another popular drug, venlafaxine, was shown increase the risk users engaging in suicidal thoughts and attempts at suicide
2/25 'Universal cancer vaccine’ breakthrough claimed by experts
Scientists have taken a “very positive step” towards creating a universal vaccine against cancer that makes the body’s immune system attack tumours as if they were a virus, experts have said. Writing in Nature, an international team of researchers described how they had taken pieces of cancer’s genetic RNA code, put them into tiny nanoparticles of fat and then injected the mixture into the bloodstreams of three patients in the advanced stages of the disease. The patients' immune systems responded by producing "killer" T-cells designed to attack cancer. The vaccine was also found to be effective in fighting “aggressively growing” tumours in mice, according to researchers, who were led by Professor Ugur Sahin from Johannes Gutenberg University in Germany
3/25 Green tea could be used to treat brain issues caused by Down’s Syndrome
A compound found in green tea could improve the cognitive abilities of those with Down’s syndrome, a team of scientists has discovered. Researchers found epigallocatechin gallate – which is especially present in green tea but can also be found in white and black teas – combined with cognitive stimulation, improved visual memory and led to more adaptive behaviour. Dr Rafael de la Torre, who led the year-long clinical trial along with Dr Mara Dierrssen, said: “The results suggest that individuals who received treatment with the green tea compound, together with the cognitive stimulation protocol, had better scores in their cognitive capacities”
4/25 New online test predicts skin cancer risk
Health experts have created a new online tool which can predict a person’s risk of developing a common form of skin cancer. The tool uses the results of a 10-question-quiz to estimate the chance of a person aged 40 or over of having non-melanoma skin cancers within three years. Factors including the age, gender, smoking status, skin colour, tanning ability, freckling tendency, and other aspects of medical history are covered by the quiz
5/25 Multiple Sclerosis stem cell treatment 'helps patients walk again'
A new treatment for multiple sclerosis (MS) has enabled some patients to walk again by “rebooting” their immune systems. As part of a clinical trial at Sheffield's Royal Hallamshire Hospital involving around 20 patients, scientists used stem cells to carry out a bone marrow transplant. The method known as an autologous haematopoietic stem cell transplant (HSCT) works by using chemotherapy to destroy the area of the immune system which causes MS
6/25 Dementia patients left without painkillers and handcuffed to bed
Dementia patients experience a ‘shocking’ variation in the quality of hospital care they receive across England, a charity has warned. Staff using excessive force and not giving dementia patients the correct pain medication were among the findings outlined in a new report by The Alzheimer’s Society, to coincide with the launch of Fix Dementia Care campaign
7/25 Cancer risk 'increased' by drinking more than one glass of wine or pint of beer per day
Drinking more than one glass of wine or pint of beer a day increases the risk of developing cancer, according to medical experts. New guidelines for alcohol consumption by the UK published by chief medical officers warn that drinking any level of alcohol has been linked to a range of different cancers. The evidence from the Committee on Carcinogenicity (COC) overturns the oft-held view that a glass of red wine can have significant medical benefits for both men and women
8/25 Vaping 'no better' than smoking regular cigarettes
Vaping could be “no better” than smoking regular cigarettes and may be linked to cancer, scientists have found. The study which showed that vapour from e-cigarettes can damage or kill human cells was publsihed as the devices are to be rolled out by UK public health officials as an aid to quit smoking from 2016. An estimated 2.6 million people in the UK currently use e-cigarettes
9/25 Rat-bite fever
A teenager was hospitalised and left unable to move after she developed the rare rat-bite fever disease from her pet rodents which lived in her bedroom. The teenager, who has not been named, was taken to hospital after she complained of a pain in her right hip and lower back which later made her immobile, according to the online medical journal BMJ Case Reports. She suffered for two weeks with an intermittent fever, nausea and vomiting and had a pink rash on her hands and feet. The teenager, who had numerous pets including a dog, cat, horse and three pet rats, has since made a full recovery after undergoing a course of antibiotics. Blood tests showed that she was infected with for streptobacillus moniliformis – the most common cause of rat-bite fever. One of her three pet rats lay dead in her room for three weeks before her symptoms showed
10/25 Taking antidepressants in pregnancy ‘could double the risk of autism in toddlers’
Taking antidepressants during pregnancy could almost double the risk of a child being diagnosed with autism in the first years of life, a major study of nearly 150,000 pregnancies has suggested. Researchers have found a link between women in the later stages of pregnancy who were prescribed one of the most common types of antidepressant drugs, and autism diagnosed in children under seven years of age
11/25 Warning over Calpol
Parents have been warned that giving children paracetamol-based medicines such as Calpol and Disprol too often could lead to serious health issues later in life. Leading paediatrician and professor of general paediatrics at University College London, Alastair Sutcliffe, said parents were overusing paracetamol to treat mild fevers. As a result, the risk of developing asthma, as well as kidney, heart and liver damage is heightened
12/25 Fat loss from pancreas 'can reverse' effects of type-2 diabetes
Less than half a teaspoon of fat is all that it takes to turn someone into a type-2 diabetic according to a study that could overturn conventional wisdom on a disease affecting nearly 3 million people in Britain. Researchers have found it is not so much the overall body fat that is important in determining the onset of type-2 diabetes but the small amount of fat deposited in the pancreas, the endocrine organ responsible for insulin production
13/25 Potatoes reduce risk of stomach cancer
Scientists have found people who eat large amounts of white vegetables were a third less likely to contract stomach cancer. The study, undertaken by Chinese scientists at Zhejiang University, found eating cauliflower, potatoes and onions reduces the chance of contracting stomach cancer but that beer, spirits, salt and preserved foods increased a person’s risk of the cancer
14/25 Connections between brain cells destroyed in early stages of Alzheimer’s disease
Scientists have pinpointed how connections in the brain are destroyed in the early stages of Alzheimer’s disease, in a study which it is hoped will help in the development of treatments for the debilitating condition. At the early stages of the development of Alzheimer’s disease the synapses – which connect the neurons in the brain – are destroyed, according to researchers at the University of New South Wales, Australia. The synapses are vital for brain function, particularly learning and forming memories
15/25 Sugar tax
The Government should introduce a sugar tax to prevent an “obesity crisis” from crippling the NHS, a senior Conservative MP and former health minister has said. Dr Dan Poulter believes that the case for increased taxes on unhealthy sugary products was “increasingly compelling”
16/25 Cancer breakthrough offers new hope for survivors rendered infertile by chemotherapy
A potentially “phenomenal” scientific breakthrough has offered fresh hope to cancer patients rendered infertile by chemotherapy. For the first time, researchers managed to restore ovaries in mice affected by chemotherapy so that they were able to have offspring. The scientists now plan to begin clinical trials to see if the technique, which involves the use of stem cells, will also work in humans by using umbilical cord material and possibly stem cells taken from human embryos, if regulators agree
17/25 Take this NHS test to find out if you have a cancerous mole
An interactive test could help flag up whether you should seek advice from a health professional for one of the most common types of cancer. The test is available on the NHS Choices website and reveals whether you are at risk from the disease and recommends if you should seek help. The mole self-assessment factors in elements such as complexion, the number of times you have been severely sunburnt and whether skin cancer runs in your family. It also quizzes you on the number of moles you have and whether there have been any changes in appearance regarding size, shape and colour
18/25 Health apps approved by NHS 'may put users at risk of identity theft'
Experts have warned that some apps do not adequately protect personal information
19/25 A watchdog has said that care visits must last longer
The National Institute for Health and Care Excellence (Nice) said home help visits of less than 30 minutes were not acceptable unless part of a wider package of support
20/25 Pendle in Lancashire tops list of five most anxious places to live in the UK
Pendle in Lancashire has been named the most anxious place to live in the UK, while people living in Fermanagh and Omagh in Northern Ireland have been found to be the happiest
21/25 Ketamine could be used as anti-depressant
Researchers at the University of Auckland said monitoring the effects of the drug on the brain has revealed neural pathways that could aid the development of fast-acting medications. Ketamine is a synthetic compound used as an off anaesthetic and analgesic drug, but is commonly used illegally as a hallucinogenic party drug. Dr Suresh Muthukumaraswamy, a senior researcher at the university and a member of the institution’s Centre for Brain Research, used the latest technology in brain imaging to investigate what mechanisms ketamine uses to be active in the human brain
22/25 A prosthetic hand that lets people actually feel through
The technology lets paralysed people feel actual sensations when touching objects — including light taps on the mechanical finger — and could be a huge breakthrough for prosthetics, according to its makers. The tool was used to let a 28-year-old man who has been paralysed for more than a decade. While prosthetics have previously been able to be controlled directly from the brain, it is the first time that signals have been successfully sent the other way
23/25 The biggest cause of early death in the world is what you eat
Unhealthy eating has been named as the most common cause of premature death around the globe, new data has revealed. A poor diet – which involves eating too few vegetables, fruits, nuts and grains and too much red meat, salt and sugar - was shown to be a bigger killer than smoking and alcohol
24/25 Scientists develop blood test that estimates how quickly people age
Scientists believe it could be used to predict a person’s risk of developing Alzheimer’s disease as well as the “youthfulness” of donated organs for transplant operations. The test measures the vitality of certain genes which the researchers believe is an accurate indication of a person’s “biological age”, which may be younger or older than their actual chronological age
25/25 Aspirin could help boost therapies that fight cancer
The latest therapies that fight cancer could work better when combined with aspirin, research has suggested. Scientists from the Francis Crick Institute in London say the anti-inflammatory pain killer suppresses a cancer molecule that allows tumours to evade the body’s immune defences. Laboratory tests have shown that skin, breast and bowel cancer cells often generate large amounts of this molecule, called prostaglandin E2 (PGE2). But Aspirin is one of a family of drugs that sends messages to the brain to block production of PGE2 and this means cancer cells can be attacked by the body’s natural defences
A persistent problem nowadays, experts reason, is that we are in a constant state of stress or anxiety, so our gut never gets the chance to do its job properly. A 2011 study in Brain, Behaviour and Immunity suggested that stress alters the structure of the microbiome. A 2012 study indicated that, in turn, gut bacteria can affect our stress responses.
There is no denying that some very modern maladies are on the increase. Irritable bowel syndrome, that spectrum of general digestive unpleasantness, afflicts an estimated 10 to 20 per cent of the UK population. More serious, perhaps, are the inflammatory bowel diseases like Crohn's and ulcerative colitis. A 2012 study published in the journal Gastroenterology indicated that inflammatory bowel diseases (IBDs) are emerging as a global problem. Incidences are far higher in Europe and North America – although there is considerably less data from developing countries. Autoimmune diseases such as lupus, coeliac disease and type 1 diabetes are also on the rise. Between 2001 and 2009, the incidence of type 1 diabetes increased by 23 per cent, according to the American Diabetes Association. And, of course, there's the No 1 Western problem – obesity.
Why, then, is there such a growth in certain diseases in the West? Some say that we are quite literally navel-gazing – a poor man working on a factory line in Hanoi has little time to moan about an upset tummy. Or is our diet – high in sugar, processed foods and artificial ingredients, while being refined and low in fibre – causing serious damage to the delicate symbiosis of our microbiome?
One emerging theory behind the imbalance is the hygiene hypothesis. This goes straight back to – you guessed it – our gut. We are exposed to bugs from the second we are born, quite literally, as our first brush with bacteria will be from the mother as we emerge from the birth canal. Studies suggest that children born by caesarean section don't get this initial burst of bacteria, and may have a weakened immune system as a result.
Similarly, as children grow up, they get dirty, put things in their mouth, kiss the dog, and essentially do lots of things to expose themselves to bacteria. But when we get trigger-happy with the Dettol and load up on unnecessary antibiotics, there is far less exposure. Of course, hygiene is good, and antibiotics have prevented far more diseases and premature deaths than they could cause. But our immune systems could be so coddled that they can't withstand the first threat of real infection.
Professor Tim Spector believes that most of the microbes in our systems are crucial for good health, but that our modern lifestyles have upset the balance. "We start life with a weakened biodiversity," he says. "The tendency towards caesarean sections, overclean environments, reliance on antibiotics, lack of fibre and a less diverse diet all contribute to a deranged microbiome."
In his book The Diet Myth: The Real Science Behind What We Eat, Spector looks beyond calorie-counting to how the food we ingest is really fuelling us, and how our gut bacteria could be influencing that – and vice versa. He conducted an experiment with the help of his son, Tom – their mini version of the documentary Super Size Me. Tom lived off a diet of McDonald's for 10 days, giving a stool sample before and after. In the short time period, the junk food had dramatically reduced the diversity of his microbiome by 40 per cent, and replaced "good" bacteria with those that can cause inflammation.
Dr David Perlmutter is another champion of the "gut brain" – and believes an imbalanced microbiome could be causing everything from Alzheimer's to autism. He has worked with patients suffering from various conditions, including Tourette's and multiple sclerosis, and claims they have seen dramatic improvements with an altered diet or procedures such as faecal transplants.
"Some of my most remarkable case studies involve people changing their lives and health for the better through simple brain-making edits to their dietary choices," he writes in his book, Brain Maker. "They cut carbs and add healthy fats, especially cholesterol – a key player in brain and psychological health. I've watched this fundamental dietary shift single-handedly extinguish depression and all of its kissing cousins, from chronic anxiety to poor memory and even ADHD."
Spector is slightly more cautious. "We are making real progress, but people don't realise how young this field is," he says. "When it comes to illness, we need much more research to discover whether a disordered microbiome is causing problems or simply making them worse. For instance, autistic children have abnormal microbiomes, but they also tend to have abnormal diets."
It is certainly a complex area to study – a handful of soil contains more microbes than there are stars in the sky, Spector says, and our bodies contain 100 trillion of them, weighing more than 4lb in our guts alone. However, he says that he can tell if someone is healthy simply by examining their microbiome – and he has examined plenty.
He is part of the British Gut Project, the UK arm of the American crowdfunding effort to get a major sample of the population's bacteria. The project has been appealing to the public for donations – monetary and faecal – to help them gain more understanding of the geographical, dietary and genetic differences in people. In return for a donation, participants get a breakdown of their microbiome, but no dietary or medical advice is given on the back of it. It may seem like an impossible quest – Spector admits Britons are sensitive about poo – but the project has been attracting about 100 volunteers a month, with 1,300 participants to date, to go with more than 3,000 in the US.
Spector believes that in the future a better understanding of the microbiome could lead to personalised diet advice. "Some people can eat meat without any ill-effects. Some people react differently to pasta, or lentils. There is even a 'skinny bacteria' – there have been tests on mice involving Christensenella. When the bacteria was transplanted into their microbiome they gained less weight."
Perhaps, then, the ultimate question is how to maintain a balanced microbiome. In his book, Perlmutter outlines his ideal diet to boost bacteria. It is rich in probiotic fermented foods like kimchi and sauerkraut, unprocessed meat and vegetables and (the good news) dark chocolate and red wine. Spector follows a similar regime. "I have cut out all processed foods – but have more coffee and dark chocolate." He says we need to think of our microbiome like a garden – we need to nourish the soil (intestines) for healthy plants (bacteria), while minimising weeds (disease-causing microbes). "It's important to remember that you are never dining alone – you are with your microbes."
- More about:
- Professor Tim Spector
- immune systems
- Digestive systems
- caesarean section
- Dr David Perlmutter
- American Diabetes Association
- bowel syndrome
- North America