What are the benefits of taking probiotics? Bacteria have a reputation for causing disease, so the idea of tossing down a few billion a day for your health might seem — literally and figuratively — hard to swallow.

But a growing body of scientific evidence offered by Doctors at Harvard Medical School suggests that you can treat and even prevent some illnesses with foods and supplements containing certain kinds of live bacteria.

Potential benefits of probiotics have been seen in the treatment or prevention of:

• diarrhoea
• irritable bowel syndrome
• ulcerative colitis
• crohn’s disease
• h.pylori (the cause of ulcers)
• vaginal infections
• urinary tract infections
• recurrence of bladder cancer
• infection of the digestive tract caused by Clostridium difficile
• pouchitis (a possible side effect of surgery that removes the colon)
• eczema in children

Probiotics and IBS

Some digestive disease specialists are recommending probiotic supplements for disorders that frustrate conventional medicine, such as irritable bowel syndrome. Since the mid-1990s, clinical studies suggest that probiotic therapy can help treat several gastrointestinal ills.

There is no doubt that having a healthy gut contributes significantly to having good health. An estimated 100 trillion microorganisms representing more than 500 different species inhabit every normal, healthy bowel.

These microorganisms (or microflora) generally don’t make us sick; most are helpful. Gut-dwelling bacteria keep pathogens (harmful microorganisms) in check, aid digestion and nutrient absorption, and contribute to immune function.

Probiotics and gut health

The best case for probiotic therapy has been in the treatment of diarrhoea. Controlled trials have shown that Lactobacillus GG can shorten the course of infectious diarrhoea in infants and children (but not adults).

Although studies are limited and data are inconsistent, two large reviews, taken together, suggest that probiotics reduce antibiotic-associated diarrhoea by 60%, when compared with a placebo.

More common than diarrhoea is the opposite problem — constipation. In a search for studies on the benefits of probiotics in treating constipation, researchers found that probiotics slowed “gut transit time” by 12.4 hours, increases the number of weekly bowel movements by 1.3, and helped to soften stools, making them easier to pass.

Probiotic therapy may also help people with Crohn’s disease. Clinical trial results are mixed, but several small studies suggest that certain probiotics may help maintain remission of ulcerative colitis and prevent relapse of Crohn’s disease and the recurrence of pouchitis (a complication of surgery to treat ulcerative colitis).

Probiotics and Covid

Recently this has of course been a major health concern, and a report in the Daily Mail confirmed that bacteria in your gut affects your immune response to Covid-19 and could influence how severely you suffer symptoms.

This was based on two studies. One was a South Korean study that reviewed pre-existing research on role of gut microbiome and the other from Hong Kong-based scientists who examined blood and stool samples from patients.

Both studies indicate a gut microbe imbalance is key in severe Covid-19 and that a person’s gut microbiome may play a role in fighting off coronavirus infection and preventing severe Covid-19 symptoms.

Each person has a unique assortment of bacteria in their gut which play a variety of roles, including in modulating the immune response. The South Korea study found people with a poorly functioning gut are more likely to develop severe Covid-19 because the lack of healthy microbes makes it easier for the virus to infect cells in the digestive tract.

Clearly probiotics have a role to play in having a healthy gut and that is essential for maintaining overall good health. Healthy diet definitely starts with a healthy diet, a nutritionist would advise that you also have good levels of vitamins C, D and the mineral zinc to help you fight infection.

Probiotics and vaginal health

Probiotics may also be of use in maintaining urogenital health. Like the intestinal tract, the vagina is a finely balanced ecosystem. The dominant Lactobacilli strains normally make it too acidic for harmful microorganisms to survive.

But the system can be thrown out of balance by a number of factors, including antibiotics, spermicides, and birth control pills. Probiotic treatment that restores the balance of microflora may be helpful for such common female urogenital problems as bacterial vaginosis, yeast infection, and urinary tract infection.

Probiotic treatment of urinary tract infections is under study but no definitive results yet.

Food sources of probiotics 

Food sources or something you probably already have in your diet, certainly if you eat fermented foods or one of the more common sources.

Yogurt is one of the most familiar sources of probiotics – the “good” bacteria that keep a healthy balance in your gut.

You can pay extra for brands with certain probiotics, but any that have “live and active cultures” may help.

Sauerkraut is also good, but choose the unpasteurised kind. The pasteurising process, which is used to treat most supermarket brands, kills active, good bacteria.

Sauerkraut and the similar but spicy Korean dish kimchi are also loaded with immune-boosting vitamins that can help ward off infection.

Miso soup made from fermented soybean paste can get your system moving. Probiotic-filled miso is often used to make a salty soup that’s low in calories and high in B vitamins and protective antioxidants.

Tempeh is made from a base of fermented soybeans and makes a type of natural antibiotic that fights certain bacteria.

Tempeh is also high in protein and its flavour is smoky, nutty, and similar to a mushroom. You can marinate it and use it in meals in place of meat.

Soft cheeses are good for your digestion, but not all probiotics can survive the journey through your stomach and intestines. Research finds that strains in fermented soft cheeses, like gouda, mozzarella, cheddar and cottage cheese are hardy enough to make it.

Kefir is now a staple on supermarket chiller shelves and is thick, creamy, and tangy like yogurt. It has its own strains of probiotic bacteria, plus a few helpful yeast varieties.

Sourdough bread again has become very popular and this San Francisco’s sourdough favourite packs a probiotic that may help digestion.

Acidophilus and butter milks provide one of the easiest ways to get probiotics as they have been fermented with bacteria.

Sour pickles are commonly known as dill pickles and if you are looking to pickles for probiotics, choose naturally fermented kinds, where vinegar wasn’t used in the pickling process.

A sea salt and water solution feeds the growth of good bacteria, and it may make these pickles help with your digestion.

Prebiotics vs. Probiotics

This can cause some confusion, but while probiotic foods have live bacteria, prebiotic foods feed the good bacteria that already live in your gut.

You can find prebiotics in things like asparagus, Jerusalem artichokes, bananas, oatmeal, red wine, honey, maple syrup, and legumes.

Try prebiotic foods on their own, or pair them with probiotic foods or supplements to add a boost.