First of all, let’s go through the terms…
- Probiotics are the good living microbes that protect us against the bad ones. The good microbes most commonly found in food and supplements include yeasts and bacteria from Lactobacillus and Bifidobacterium groups.
- Prebiotics are dietary fibres that assist the growth of probiotics by providing them nutrients.
- Synbiotics refer to products that contain both probiotics and prebiotics.
- CFUs is an abbreviation for “colony forming units”. It’s essentially used as a measure of the number of living microbes.
Not all microbes are bad
There are good and bad microbes. The good ones are those that normally occupy the surfaces of our body that are exposed to the environment, i.e. our skin, our digestive tract from mouth to anus, our respiratory tract from nose to lungs, our urinary tract, etc. The good bacteria crowd out and produce toxins that kill the bad bacteria, fungi and parasites, preventing them from taking over, thus keeping us healthy. Apart from that, the good bacteria also help digest food, process and produce important vitamins, manage and eliminate toxic substances.
Many factors can cause the bad bacteria to take over, for instance, the use of antibiotics, stress, poor nutrition and serious illnesses. This can in turn lead to a lot of health issues including digestive problems, constipation, infection, etc.
Benefits of probiotics
The good bacteria may
- Support healthy digestive system – Improve acid reflux; relieve diarrhea (especially viral- or antibiotic induced), constipation and irritable bowel syndrome
- Improve oral health – Reduce plaque build-up, banish persistent bad breath
- Support urinary and female genital tract health – Prevent urinary tract infection and vaginal thrush
- Improve immune health
- Relieve allergies including eczema and hay fever
Note: Despite the vast amount of research conducted, more conclusively evidence are still needed to support those health claims.
Side effects associated with probiotics are rare, and if occur, normally only involve mild digestive problems such as bloating.
You are advised to consult your doctor before taking any probiotic dietary supplements especially if you have any health conditions.
Sources of probiotics
Fermented food including yoghurt, Kombucha, kefir, tempeh, miso, sauerkraut, kimchi, etc. are good sources of probiotics. Apart from fermented food, probiotics are also incorporated into some food products such as milk formula.
Alternatively, there are also dietary supplements to boost up the level of good bacteria. These supplements come in different formulations, ranging from tablets and capsules to liquid forms. Some of these need to be refrigerated, some don’t. However, all of the probiotic products need to be stored in places away from extreme heat, light and moisture.
What’s more, probiotics are now also formulated for external use in the form of cream and shower liquid.
Tips on supplementation
- Choose products that contain multiple strains rather than single isolated strain.
- Choose supplements that contain prebiotics. This will help promote the growth and activity of ingested probiotics and the existing good bacteria lining our body.
How about the total CFU? Well, it’s thought that the variety of bacteria strains (and their ratio) is more important than the CFU of a single strain of bacteria. As it’s been proposed that overly high amount of one single strain may compromise the healthy bacteria balance.
In a nutshell, good microbes are crucial to us in maintaining good health, however, there is no strong conclusive evidence to support the benefits of supplementation in healthy adults. Despite that, it is definitely untrue to go as far as saying that probiotic supplements are worthless. More evidence are still needed to determine the usefulness of probiotic supplements.
Check out the following resources if you would like to find out more about probiotics:
- Probiotics: In Depth by NIH outlines what the science says about the effectiveness and safety of probiotics.
- No evidence probiotics are beneficial for healthy adults by PubMed Health explains without bias the latest scientific review on probiotics in layman’s terms.
- How to Choose the Best Probiotic Supplement by Dr. David Williams explains what you need to consider when choosing a probiotic supplement.