As we learn more about the importance of gut microbes (the microbiome) to our health, at-home testing kits might seem useful tools.
These kits – costing from £10 to over £300 – typically involve collecting a stool sample that’s sent away for analysis.
But a recent US study cast doubt on their accuracy. In the research, published in the journal Communications Biology, 21 samples from the same stool were sent to seven different companies offering at-home microbiome checks.
Results varied greatly regarding what was considered a ‘healthy’ microbiome. The researchers concluded the results were unreliable and these at-home tests may be a waste of money.
But these are not the only at-home gut tests available, with products claiming to detect everything from food intolerance to inflammatory bowel disease. We asked experts to assess a selection.
As we learn more about the importance of gut microbes (the microbiome) to our health, at-home testing kits, which typically involve collection a stool sample, might seem useful tools
Irritable Bowel Syndrome
IBS Test, £219.99, gettested.co.uk
This test supposedly provides those with IBS with a ‘thorough analysis’ of their digestive system
CLAIM: The maker says this stool test provides those with IBS with a ‘thorough analysis of your digestive system and intestinal flora’. Results take around two weeks.
EXPERT VERDICT: ‘IBS is diagnosed through a combination of symptoms including abdominal pain, cramp, bloating and a variable bowel habit – there’s no one cause,’ says Dr Richard Sarsam, a consultant gastroenterologist at Circle Reading Hospital.
‘Knowing the levels of yeast and bacteria in the gut will not help patients manage their IBS symptoms. This test is a waste of money.’
Food intolerance
FoodMarble Aire 2, £249, foodmarble.com
This palm-sized device measures levels of methane and hydrogen in the breath, which is meant to indicate how well foods have been digested
CLAIM: You blow into the palm-sized device, which measures levels of methane and hydrogen in the breath. The maker says these indicate how well foods have been digested. You receive a ‘breath score’ via an app.
EXPERT VERDICT: ‘I have no doubt that this gadget accurately measures the gases we produce when eating – because that technology is quite simple,’ says Professor Peter Whorwell, a gastroenterologist at Wythenshawe Hospital in Manchester.
‘But my worry is that people might use it after every meal, then use the results to cut out food and restrict their diets.
‘We all produce gases as we digest our food, so that in itself is not unusual and we shouldn’t worry unduly about it.
‘Also, if you did this test after a normal meal, with lots of different foods and producing lots of gases, you would not know which you may have an intolerance to.
‘To use this device meaningfully, you would need to eat one food item at a time, measure the gas it produces and then repeat. I doubt if anyone would do that.
‘If you suspect you may have an intolerance, see a dietitian.’
Excess gas
Small Intestinal Bacterial Overgrowth (SIBO) Test Kit, £185, gutandhealth.co.uk
SIBO is a fairly common condition where abnormal bacterial growth causes excess hydrogen and methane production
CLAIM: The makers say this kit uses a ‘well-proven method for screening patients for SIBO’ – this is a condition where abnormal bacterial growth in the small intestine causes excess hydrogen and methane production.
The test involves fasting overnight, then drinking the supplied lactulose – a sugary solution – before providing breath samples into tubes every 20 minutes over three hours. The ten samples are then sent away for analysis.
EXPERT VERDICT: ‘SIBO is a fairly common condition where bacteria colonise the small bowel – sometimes following surgery that disrupts the anatomy of the gut, or due to impaired gut motility [movement],’ says Dr John Wong, a consultant gastroenterologist at Circle Meriden Hospital, Coventry. ‘This excess of bacteria leads to increased hydrogen and methane – causing bloating, diarrhoea, cramp and flatulence. It’s usually treated with antibiotics.
‘The technology here is reliable and simple – we use similar tests in clinic – but at home, without supervision, human error could easily throw up false results.
‘However, there is a role for these kits. If you have had tests ruling out more serious issues, you could take the results to your GP, for instance, to speed up treatment for SIBO or a referral to specialist.’
General gut health
myBioma Basic Test Kit, £105, mybioma.com
The results of this test include an assessment of your microbial diversity and recommendations of what to eat and drink to improve gut health
CLAIM: ‘For anyone who wants to improve their gut health.’ The kit contains a collection stick, tube and prepaid envelope to a lab in Austria. The results include assessment of your microbial diversity (a sign of gut health) and recommendations of what to eat and drink to improve gut health.
EXPERT VERDICT: ‘There isn’t an agreed definition of a good or balanced microbiome – each person’s is unique, like a fingerprint,’ says Professor Lindsay Hall, chair of microbiome research at the University of Birmingham.
‘In clinic, doctors usually use targeted stool tests for specific problems such as infection or bleeding, rather than broad microbiome profiling.
‘A test like this, which lists what the microbiome is composed of, is hard to interpret in isolation. Your microbiome also changes over time, so one test isn’t very informative.
‘If you’re simply curious, a home kit may be fun to look at – but don’t rely on it for a diagnosis.’
‘Leaky’ Gut
Leaky Gut Test Complete, £339, verisana.co.uk
This test analyses a stool sample for high levels of zonulin, a protein that regulates the permeability of the gut wall
CLAIM: This test analyses a stool sample for high levels of zonulin, a protein that regulates the permeability of the gut wall. Results take around two weeks and are sent by email.
EXPERT VERDICT: ‘The term “leaky gut” refers to the gut’s mucous lining becoming more porous, meaning toxins and bacteria can pass into the bloodstream,’ says Professor Whorwell.
‘This test does have a scientific basis in that zonulin plays a part in how leaky a gut is – but other indicators are involved. Even stress can make our gut leaky.
‘And it’s premature to say your zonulin level can tell you whether you have a leaky gut. There hasn’t been much research into how this protein works and it’s not measured in a clinical setting.
‘In fact, very little is known about leaky gut. We do not know what symptoms it causes or how it can be tested for or treated.’
Parasitic infection
Advanced Gut Bacteria, Worm and Parasite Test, £249, selph.co.uk
This kit checks a stool sample for infection caused by bacteria including C.diff ; viruses such as norovirus ; and other parasites
CLAIM: This kit checks a stool sample for infection caused by bacteria including C.diff; viruses such as norovirus; and other parasites. You send off the sample, and the results include treatment and recommendations.
EXPERT VERDICT: ‘This kit uses PCR testing – the most sensitive and best method for detecting infections – so I would expect it to be reliable,’ says Paul Hunter, a professor of medicine at the University of East Anglia, specialising in infectious diseases.
‘I would consider buying this test if I had returned from an extended overseas trip such as to South-East Asia and Africa, to exclude an infection where there are often no obvious symptoms.
‘I would also use it if I had diarrhoea that wasn’t improving after a couple of days and couldn’t get a GP appointment. I would not recommend it for people with none of these factors though.’
Inflamed bowel
ArcGenics Bowel Inflammation Test Kit, £16, amazon.co.uk
This rapid home test is described by its maker as a ‘reliable marker for bowel inflammation’
CLAIM: This rapid home test detects raised levels of calprotectin, a protein released by white blood cells when the intestinal lining becomes damaged – described by its maker as a ‘reliable marker for bowel inflammation’. A stool sample is mixed with a reagent, shaken and two drops placed on a lateral flow. A result appears in five minutes – a line indicates a positive result.
EXPERT VERDICT: ‘Measuring calprotectin in poo is a very effective way of testing for bowel inflammation,’ says Chris Probert, a professor of gastroenterology at the University of Liverpool.
‘Levels are elevated if the bowel is inflamed due to infection or an inflammatory bowel disease such as Crohn’s. Patients should not try to self-diagnose, though – any raised calprotectin level without a known diagnosis should be discussed with a GP.
‘This home kit could be useful if you had diarrhoea for six weeks or more. But if you have bleeding from your bottom, see your GP.’
Test for bacteria linked to stomach ulcer
Stomach Ulcer (H.pylori) Rapid Test, £10, myhealthchecked.com
CLAIM: This tests for Helicobacter pylori, bacteria that can cause stomach bloating and heartburn, from a stool sample. A line on the test appears if it is found, within ten minutes.
EXPERT VERDICT: ‘H.pylori is common,’ says Dr Matyas Fehervari, a gastrointestinal consultant at Nuffield Health Tunbridge Wells Hospital.
‘It damages the protective stomach lining, meaning acid there can cause an ulcer. If treated – either with antibiotics to kill off the bacteria, or proton pump inhibitors to reduce stomach acid – an ulcer should heal in six weeks.
‘This method of testing is not reliable. A positive result probably means you have
H.pylori – but it can also show a false negative, giving you false reassurance.
‘If you have worrying symptoms, see your GP for clinical tests including endoscopies, biopsies and stool tests.’
