With gut health such a priority these days (and with good reason), more and more people are turning to probiotics, whether that's in the form of foods like yoghurt and kombucha, or probiotic supplements.
But if you've ever tried shopping for probiotic supplements, you may have been overwhelmed by the options -- how many millions of CFUs (what are they, anyway?) and which long-worded, unpronounceable strains do we need?
With help from dietitians and a pharmacist, here is everything you should to know about probiotics and probiotic supplements.
What are probiotics?
"Probiotics are live 'friendly bacteria' that are good for our health, especially our digestive system," Anna Debenham, accredited practising dietitian from The Biting Truth, told HuffPost Australia.
"They are naturally found in our body, but can also be found in some foods and supplements we eat. They act to reduce the number of harmful bacteria in the gut, thereby improving our overall health."
Probiotics help our bodies in a number of different ways:
- Enhance immune function
- Increase resistance to infection
- Help prevent diarrhoea resulting from antibiotic therapy
- Improve digestion and bowel movements
- Help protect against disease
- May assist with weight maintenance
"The microorganisms in probiotic products are identical or similar to the microorganisms that normally live in our bodies," pharmacist and personal trainer Holly Louise explained.
"Due to our busy lifestyles, poor food choices and reduced food quality, many of us can suffer from issues with digestive health as a result of unbalanced gut bacteria, which is where probiotics can play a key role."
How does a probiotic supplement work?
Under normal conditions, good bacteria should make up about 90 percent of the population of microbes living in our gut.
"But factors like diet, stress, illness and medications can skew the ratio of good-to-bad and lead to disorders such as gastrointestinal distress, inflammation, eczema, a weakened immune system, diarrhoea or constipation," Louise said.
"Probiotics help to restore the natural balance of bacteria in our gut when it has been compromised by these factors.
"Some probiotics contain a single strain of bacteria or yeast, while others contain multiple strains. Different strains of the same species can result in different effects on health."
For instance, certain strains of probiotics support immunity, while others target digestion and even weight regulation.
Ultimately, it's about finding what is causing imbalance in your gut, and the best way to do this is to speak to your doctor.
What about the strains?
"Most often, the bacteria contained in probiotic products come from two groups, Lactobacillus or Bifidobacterium," Louise said.
"Within each of these groups, there are different species (for example, Lactobacillus acidophilus and Bifidobacterium bifidus), and within each species there are different strains. Saccharomyces boulardii, also a common probiotic, are yeasts, which are different from bacteria and also offer different health benefits.
"Because these diverse organisms can have different effects on the body, it's difficult for scientists to determine their exact health benefits and the ways they may work."
When would we need a probiotic supplement?
Unfortunately, things like stress, illness and poor diet can negatively impact our gut's friendly bacteria.
"Bad or 'unfriendly' bacteria grow when we eat a processed diet that's high in sugar and unhealthy fats, low in fibre and prebiotics, or when we take antibiotics and other drugs," Alexandra Parker, accredited practising dietitian from The Biting Truth, told HuffPost Australia.
"Imagine your gut is like a garden -- when you stop looking after your garden and the weeds take over, it can get into trouble. The same happens in your gut when bad bacteria take over (for example, sickness, disease, diarrhoea).
"In short, the microbial ecosystem in the gut has to be healthy for you to be healthy. When our gut bacteria are out of balance, we can become sick. When you have too many bad bacteria this can become a problem."
That's where probiotics come into play, as they help to improve the balance and therefore our overall health.
Can we get enough friendly bacteria from food?
Many foods contain probiotics and should be the first line of defence, Debenham explained. However, it can be difficult to get enough probiotics through food alone.
"Our approach is always to try food first and some studies even suggest that food sources provide probiotics in a more readily available form for absorption and digestion," Debenham said.
Probiotics are found naturally in yoghurts and fermented foods such as Yakult, kefir, sauerkraut, miso soup, tempeh, kimchi and kombucha tea.
"Choosing food sources of probiotics means you'll get added nutrients -- for instance, a probiotic yoghurt also provides your body a rich source of calcium, protein and B vitamins," Parker said.
"If you want a top up, can't tolerate fermented foods or have recently been taking antibiotics or had a bout of diarrhoea, then probiotic supplements can be a good addition to your diet."
However, many people still need to supplement with probiotics -- and the quality is key.
"You need to take a probiotic supplement to ensure you are consuming adequate probiotics in your diet, especially if you are treating a particular condition," Louise said.
"There is a huge difference between the pharmaceutical-grade probiotics that are used in clinical trials and the probiotic foods sold in shops."
How to choose the best probiotic
The first and best point of contact when figuring out whether you need to supplement (and what with) is the GP.
"A general probiotic is not suitable for everyone because the reasons for imbalance are very individual. People need to gain an understanding of their own gut health, which can be achieved by working with their doctor and providing a stool sample," Debenham said.
When you and your GP know which condition or illness to treat, if any, then it's best to look for a product that contains the specific strains which have been proven to assist in the treatment of that condition.
Generally, here are some important things to look out for when choosing a probiotic. Note that it is the strain of probiotic that is most important.
"Check the genus, species and strain of the microorganisms (for example, Lactobacillus acidophilus DDS-1). Some products don't list the strain, which is important to know as different strains provide different benefits," Louise said.
"Look at the number of organisms contained in a single dose and the directions on how to take the product. As a guide, choose a probiotic that contains at least seven strains and five billion 'colony forming units' (CFU).
"Check the potency, too. It is important to choose a product that ensures the living microbes are in fact still living at the time of purchase. Some supplements may provide a live microbe count 'at the time of manufacture', which does not guarantee this same amount will be available when you buy the product or take it."
Storage is also essential to ensure the probiotic lasts and does its job.
"Some forms need to be refrigerated, while others only need to be stored at room temperature. Probiotics should always be kept away from moisture and heat," Louise said.
"Quality is important. You want a product that is free of chemicals and other ingredients that could potentially upset your gastrointestinal tract. Check the label for potential irritants and ingredients that you may be intolerant to."
How long should we take them for?
Unfortunately, taking a probiotic does not lead to long-term colonisation and survival in the digestive tract, Parker explained.
"Probiotics must be taken regularly otherwise they will be diluted out of the colon within one to two weeks of ingestion, unless there is continuous intake.
"The recommended dosage of probiotics is still an important area that needs to be addressed in future research. A larger dose does not necessarily mean an enhanced effect and multiple strains does not necessarily equate to a more effective product."
"I also highly recommend consuming probiotic-rich foods and beverages in conjunction with a supplement," Louise added.
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