Probiotics have multiple health benefits

New studies on probiotics for brain, immune system, allergies, blood pressure, weight loss; even rheumatism

New studies on probiotics show even more benefits than originally thought.

No lesser authorities than Harvard Medical School and Scientific American have both published lengthy reports on probiotics in the last few weeks (Summer 2019). They significantly extend the list of what improving your gut health can do for you.

Perhaps that’s not so surprising as your gut health directly influences your overall health.

A large-scale review of the role of probiotics in health published in The American Journal of Human Nutrition makes four key points:

  • The human diet once contained many times more beneficial bacteria than today
  • Allergic diseases, asthma, chronic inflammatory bowel disease, Crohn's disease, ulcerative colitis, diabetes, eczema, osteoporosis and arthritis are all strongly on the rise.
  • These diseases arise from weakening of probiotic/immune defence mechanisms in the gut.
  • Probiotic therapy shows ‘great promise for the prevention and treatment’ of all these and other problems.

The ‘good versus bad’ daily battle going on inside you

Your intestines are home to a mixed community of trillions of bacteria – a world of microscopic live organisms, some of which are harmful.

The harmful bacteria produce and pump out toxins, activate carcinogens (that can trigger cancerous cells) and cause chronic inflammation, which itself is a cause of many so-called age-related diseases.

If the harmful, pathogenic, bacteria are too numerous and not counter-balanced by beneficial bacteria, it can allow infections like salmonella and E. coli, to take hold. Or permit inflammatory conditions like IBS and ‘leaky gut’ to develop, and yeast infections like thrush and candida to grow.

The role of the ‘good’ bacteria - probiotics - is to counterbalance the bad, crowding them out and weakening their influence.

That is why there is now good evidence that increasing your intake of probiotics can reduce the impact of IBS, reduce or even prevent yeast infections and regularise digestion, so both helping to resolve constipation and stopping diarrhoea.

We’ve known for some time that your microbiome – the mix of bacteria in your gut – is central to a strong immune system, and for improving the absorption of nutrients. It’s vital in generating vitamin B12, which is essential for energy. But now research shows that the microbiome can directly affect cognitive function – and mood.

That’s because there is a direct connection or ‘hotline’ between the brain and the gut via the vagus nerve.

Boost your good bacteria by increasing probiotic intake

You can restore the balance between good and bad bacteria by eating probiotic foods, which are largely fermented foods like sauerkraut, miso, kefir, kombucha, pickles and sourdough bread. (‘Pro’ means ‘for’ and ‘biotic’ means ‘life’).

Sauerkraut is a great probiotic food

Fermentation occurs when the sugar in carbohydrates is converted into organic acids in an oxygen-free environment – your stomach. That acidic environment encourages the growth of beneficial probiotics and the suppression of pathogenic ones.

You will not be surprised to learn that a recent study at the Baylor College of Medicine Cancer Center in Houston showed that a quality diet - like the Enhanced MIND diet – not only reduced the risk of cancer, Alzheimer’s and heart disease, but created a much healthier microbiome.

After all our microbes eat what we eat!

The opposite is also true. A typical high fat, high sugar intake encourages the proliferation of harmful bacteria.

You can also directly restore the balance of your microbiome by taking a probiotic supplement, thus increasing the ratio of ‘good’ to ‘bad’.

The supplement needs to contain both Lactobacillus (L) and Bifidobacterium strains because different probiotics have different functions and colonise in different places in the gut.

The Big Six Probiotic strains

Although there are over 100 species of gut bacteria, a fairly small number have dominated research – and the following generally head the list of the most effective.

Lactobacillus strains

These break down lactose – the sugar in milk – into lactic acid. Lactic acid helps blocks many harmful bacteria and boosts the body’s absorption of minerals, such as magnesium, calcium, copper and iron. Lactic acid also ferments carbohydrates – an important step in energy production.

⊗ Lactobacillus acidophilus abbreviated to L. acidophilus. This species helps maintain a healthy status of your intestinal walls, so it helps fight ‘leaky gut syndrome’. It supports proper digestion, nutrient absorption and immune function. It is used clinically to stop diarrhoea caused from viruses or bacteria.

L. plantarum. This probiotic species has an anti-inflammatory effect making it useful in cases like IBS (Inflammatory Bowel Syndrome). It makes a natural antibiotic in the intestines called lactolin and produces the amino acid L-lysine, which is also antiviral.

L. rhamnosus. Hundreds of studies support this probiotic. It is effective in treating diarrhoea, and in relieving IBS - as such patients generally have low natural levels of Lactobacillus and Bifidobacterium bacteria). Several studies have found L. rhamnosus can also help relieve, and possibly prevent, urinary tract infections (UTIs). Since it too produces lactic acid, it is important for overall gut health and energy production.

L. casei.  Research shows that this species, too, can be helpful in cases of IBS, and in the more serious IBD (Irritable Bowel Disease). It helps counteract Helicobacter pylori infection, which causes stomach ulcers. A double blind 2014 clinical trial on Lactobacillus casei reported in the International Journal of Rheumatic Diseases showed ‘significant effects’ and concluded:

Probiotic supplementation may be an appropriate adjunct therapy for rheumatoid arthritis patients and help alleviate symptoms”.

Bifidobacterium strains

This type of bacteria lives in the lining of the large intestine and the vaginal tract. It is effective against excess yeast and modifies the gut pH level, which protects against harmful bacteria. Like Lactobacillus, it increases the absorption of magnesium, iron, calcium and zinc.

It does something extra that is very important. Bifidobacterium also encourages the gut to ferment dietary fibre to produce a short chain fatty acid called butyrate.

Butyrate is a major source of energy for cell production and repair. It has also been shown to be anti-inflammatory and significantly reduce the risk of IBS, IBD and even colon cancer.

Indeed, a recent study has shown that feeding a Bifidobacterium probiotic, Bifidobacterium longum, to mice with cancer slowed down tumour growth. Further, when that probiotic supplement was combined with a new immunotherapy drug called a check-point inhibitor, the mouse tumours actually disappeared! Human trials are needed.

Butyrate also helps protect the integrity of intestinal walls – and is therefore indicated in cases of ‘leaky gut’ syndrome. In this condition, gaps in the intestinal walls allow bacterial toxins and undigested food particles to pass into the bloodstream.

Finally, because butyrate downregulates inflammation, it has a role in protecting against both diabetes and heart disease.

Bifidobacterium lactis (also known as Bifidobacterium animalis) aids digestion and strengthens the immune system.

Streptococcus thermophilus

Streptococcus thermophilus (also known as Streptococcus salivarius) produces natural antibiotic compounds in the gut that help prevent and fight infections like pneumonia and C. difficile, and may help prevent ulcers. Solid research shows it reduces diarrhoea caused by antibiotics.

Recent research on health benefits from probiotics

The last section included some very significant health advantages for probiotics. But recent research offers even more.

Reduced allergy symptoms

A 2017 issue of The American Journal of Clinical Nutrition reported on a study of people who suffered from mild seasonal allergies. One-half got a supplement that contained both Lactobacillus and Bifidobacterium, the other half took a placebo. After 8 weeks, the probiotic group reported fewer allergy symptoms.

Blood pressure reduction

An Australian meta-analysis in the journal Hypertension, summarising the results of 9 other studies), reported on 543 adults with both normal and elevated blood pressure who were given a probiotic supplement. The findings were that:

“Probiotic consumption significantly reduced systolic blood pressure by 3.56 mm Hg compared to control.”


“Probiotic consumption also significantly reduced diastolic blood pressure by 2.38 mm Hg compared to control.”

Systolic blood pressure is the blood pressure in the arteries when the heart beats. Diastolic blood pressure is the blood pressure in the arteries between heart beats.

Although statistically significant, these overall reductions are modest. However, the reduction in blood pressure was highest in borderline or high blood pressure patients.

The report concluded that you need to take the probiotics for at least 8 weeks to see an effect – and that using multiple species of probiotics resulted in significant reductions in systolic and diastolic blood pressure, whereas using a single species did not.

Perhaps even more interestingly, the report confirmed that: “Using a dose of at least 10 billion colony-forming units (CFUs) per day resulted in significant reductions in systolic and diastolic blood pressure, whereas using lower doses did not”.

The dose levels needed to tackle other problems like IBS or candida are also in the billions.

Bone strength

It’s not generally appreciated that osteoporosis is a disease that is linked to changes in the immune system as well as calcium metabolism. Recently multiple studies, summarised in a 2017 report at Michigan State University, showed that improving the composition of the microbiome via probiotics enhances the immune system and translates into improved bone density and reduced levels of osteoporosis.

This is partly because probiotics help the absorption of minerals required for healthy bone including calcium, phosphorous and magnesium. And partly because improved gut balance improves the functioning of hormones that influence the building of bone.

The report concludes:

“Modification of the gut microbiota, by ingesting probiotics, could be a viable therapeutic strategy to regulate bone remodeling under a variety of conditions that lead to bone loss and osteoporosis.”

The strains that seem to have the best effect include Lactobacillus casei, L. rhamnosus, L. acidophilus, and Bifidobacterium longum.


A common side-effect of irritable bowel syndrome (IBS) is mild or even moderate depression. A 2017 issue of Gastroenterology reported on a small (44 person) group of people with this level of anxiety or depression.

The group took a daily dose of the probiotic Bifidobacterium for 10 weeks. A control group took a placebo. At the end of the study, 64% of the probiotic group had lower depression scores compared with the control placebo group and improvements on a quality of life scale.

Probiotics can help depression

Of course, a therapy like probiotics on its own is not necessarily going to make huge difference to mental well-being. But combining this with the MIND Diet – or better still the Enhanced MIND Diet can.

The Enhanced MIND Diet builds on and improves even the Mediterranean Diet by adding the best from Japanese and other healthy diets – including Omega 3 fatty acids and especially DHA, which is vital for brain health.

This type of diet cuts inflammation, which, according to numerous studies, plays a key role in many brain disorders. These include not only depression but probably Alzheimer’s.

Your brain is also what you eat!

Improved brain function in Alzheimer’s patients?

The gut and brain are connected by the longest nerve in the body, called the vagus nerve.

When your brain senses trouble—the fight-or-flight response—it sends warning signals to the gut, which is why stressful events can cause digestive problems like a nervous or upset stomach.

In the same way this connection explains why serious gastrointestinal issues like IBS, Crohn’s disease, or chronic constipation, can result in bouts of anxiety or depression. And, therefore, why probiotics may help alleviate depression. And why probiotics might improve brain function in Alzheimer’s patients.

A 2016 study published in Frontiers in Aging Neuroscience reported on 60 Alzheimer’s patients who took milk that included four probiotic bacteria species for 12 weeks. The strains were Lactobacillus acidophilus, L. casei, Bifidobacterium bifidum, and L. fermentum. There was a ‘statistically significant’ improvement of cognitive function compared with those who drank regular milk.

Although researchers do not yet know how gut bacteria influences behaviour, one theory is that a leaky gut may allow compounds to pass into the blood stream that harm the brain. By reducing the permeability of the intestinal walls, certain probiotics like Lactobacillus and Bifidobacterium may help prevent this leakage.


One well researched benefit of probiotics to combat bacterial and yeast infections. A 2014 paper in the Journal of Lower Genital Tract Disease reviewed many clinical trials over a 20-year period. Most studies showed that Lactobacillus probiotics were able to cure bacterial vaginosis and reduce its recurrence. (Vaginosis is an infection caused by an imbalance of good and bad bacteria in the vagina.)

Support for weight loss

Claims that probiotics may aid weight loss have been controversial until recently. However, a meta-analysis published in 2016 by the International Journal of Food Sciences and Nutrition examined 25 trials that involved 1,931 healthy adults. It concluded that

“Consuming probiotics could reduce body weight and BMI, with a potentially greater effect when multiple species of probiotics were consumed.”

But how? We’ve already seen there is a gut-brain axis. We have all experienced it as the gastric butterflies that come with love or nervousness, the signals from the gut to the brain that we are hungry, and the signal that we need some ‘comfort’ foods, even though we aren’t hungry.

The suggestion is that probiotics work via this gut-brain axis, increasing the release of a hormone called GLP-1 that reduces appetite and slows the absorption of dietary fat.

A 2019 report in BioMedical Research International supports this, proposing that probiotics aided weight loss due to ...

“... their ability to alter the intestinal microbiota, re-model energy metabolism, and alter the expression of genes related to thermogenesis.”

Thermogenesis is the production of body heat especially following eating.

The reduction in body weight from probiotics alone was modest, but statistically significant, suggesting that taking a multi-strain probiotic supplement alongside a diet is worthwhile.

Potential to reduce childhood obesity

We know that antibiotics kill both good and bad bacteria, altering and impoverishing the composition of the microbiome.

New work by Professor Martin Blaser of New York University School of Medicine indicates that this change causes a hormone that regulates appetite (called ghrelin) to stay elevated. This in turn encourages people to keep eating beyond what they need. Normally, ghrelin levels fall after eating and you feel full.

Blaser is the author of Missing Microbes: How the Overuse of Antibiotics Is Fuelling Our Modern Plagues. He notes that most children, as they grow up, are exposed to multiple doses of antibiotics for complaints like ear and throat infections. This inevitably alters their microbiome and, he speculates, it is the following sequence that may help explain the rising tide of childhood obesity:-

  1. Antibiotics adversely change the balance of good and bad bacteria in the gut ⇒
  2. This affects the normal functioning of the hormone ghrelin ⇒
  3. This means normal hunger signals are weaker ⇒
  4. And therefore the individual overeats.

Add the effect of more sedentary lifestyles and the ubiquity of high-calorie food, and it is a credible hypothesis.

Since there is now good evidence that a good multi-strain probiotic is totally safe and can improve digestion, help reduce the severity of allergies and improve the absorption of nutrients, it makes sense to ensure that a programme of antibiotics in childhood is followed by a month of probiotics as a preventative measure.

This is a suggestion made by Professor Blaser himself in an article in Science.

Here is another important reason for ensuring children have a probiotic after antibiotics.

An immunologist at Chicago University first gave mice an antibiotic, then subsequently fed them with peanut protein. She found the peanut protein leaked through the gut barrier into blood circulation – and they developed a peanut allergy.

Several researchers now believe that a major cause of the rise in childhood allergies may be microbial imbalances caused by previous courses of antibiotics impoverishing the microbiome and causing auto-immune diseases. That may even include autism.

Beware heartburn meds overuse can lead to infections

Antacids or acid blocker medications, (called proton pump inhibitors), are widely prescribed and are common over-the counter drugs. It seems they adversely affect gut bacterial diversity, creating a niche where Salmonella and C. difficile can grow.

That imbalance can lead to infections, says a report from the University of Groningen in Holland. Consequently, many health researchers believe antacids are over-prescribed.

Is our environment too clean?

Several studies have linked childhood environments that are more ‘bacteria rich’ with a lower later risk of inflammatory bowel diseases. Environments, for example, like farms, and households with pets. On the other side of the coin, studies have also linked low microbial diversity with several autoimmune diseases, like IBS and Type 1 diabetes.

So maybe all those anti-bacterial sprays are doing more harm than good?

Why fibre is so vital in your diet

The gut flora of African and South American peoples (and European vegans) are generally far more varied than those of most people in Europe or North America – and this is almost certainly due to the far higher levels of fibre in the diet. Early hunter-gatherers probably ate 10 times more fibre than we do in the West.

As we have already seen, this fibre (called prebiotics) is food for probiotics and fermented by them in the gut to produce butyrate, which in turn lowers the risk of inflammatory bowel diseases, colon cancer, heart disease and diabetes.

Indeed Justin Sonnenburg, a Stanford University microbiologist, traces a clear path to the range of modern health threats. Our modern fibre-deficient Western diet means the ‘good’ bacteria in our gut have less to feed on. This results in less short-chain fatty acids like butyrate in the gut, and this leads, he states, to ...

“... a simmering state of inflammation which is really the underlying cause of all the diseases like cancer, heart disease, allergies, asthma and inflammatory bowel disease”.

Inevitably Big Pharma is creating drugs to encourage the creation of butyrate. But why not simply up your fibre content from vegetables, beans, fruits and whole grains?

If you do, research clearly shows that this will also change your microbial profile from one linked to overweight to one associated with a leaner physique.

A further study shows that when bacteria are short of fermentable fibre, they can begin to feed on the mucus lining of the gut, causing leaky gut, inflammation and illnesses like colitis, IBS and IBD.

SUMMARY: Health and medicinal benefits of probiotics

1--The use of probiotics as a medicine is not new – probiotics in fermented yogurts have been used for at least 2,000 years. But yoghurt is not usually the best source of probiotics because the strains are limited, the dose obtained is either unknown or often low, and the probiotic element may not survive the acidy of the stomach. See

2--A multi-strain probiotic almost always works best.

3--The evidence is very strong for using probiotics ...

  • After antibiotics, for both adults and children
  • For preventing stomach problems when travelling in certain countries
  • For treating Irritable Bowel Syndrome (IBS)
  • For reducing the severity of diarrhoea or constipation.

4--The evidence is strong for probiotics ...

  • In cases of so-called leaky gut syndrome
  • For fungal infections like candida or yeast infections like thrush.

5--The evidence is persuasive  for using probiotics ...

  • To reduce allergy symptoms and eczema
  • As additional support in any programme to reduce blood pressure or weight
  • As adjunct support for rheumatoid arthritis and osteoporosis.

6--It is worth considering probiotics for improving the immune system generally.

7--The evidence, we believe, is only moderate that probiotics may help mood and improve cognition in Alzheimer’s patients. But worth trying, especially as we know that the 90% of serotonin (which modulates cognition and mood) is produced in the gut.

8--Change can be fast. Data from hundreds of studies shows that the balance in your microbiome can be changed towards health in as little as two weeks from daily probiotics – ideally coupled with an increased daily intake of fibre.

MicroBiotic Plus  a multi-strain probiotic supplement

We have taken all this research into consideration is developing the probiotic supplement Microbiotic Plus. This is a multi-strain probiotic (with prebiotic fibre) that was developed from research at Nebraska University – a world centre for probiotic research.

MicroBiotic Plus includes the Big Six ‘cocktail’ strains of probiotic, plus a super-hardy strain called Bacillus coagulans ProDura™. This strain is often used for patients with IBS and IBD and is so powerful that it can survive years of extreme conditions. See

According to the drug medical dictionary RxList, Bacillus coagulans is even being prescribed to help prevent the formation of cancer-causing agents.

Should I take a probiotic supplement if I am healthy?

Finally, if gut health is so central to health, should you take a probiotic supplement even if you are healthy?

So far, I think not. But I definitely recommend a probiotic supplement if you have any of the health issues mentioned in this article, or are travelling overseas where different bacteria can cause tummy upsets and diarrhoea. And I do advise EVERYONE to increase their intake of dietary fibre.

This article is an update of a previous report on probiotics you can find at

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