Probiotics Learning Lab Impartially created by the experts at OptiBac

A common question in regards to probiotics is whether it is ok to take probiotics every day. Whilst there may be a few exceptions to this rule, the general answer is yes, it's safe, and often recommended to take them daily.

Probiotics are safe to take every day, preferably at breakfast time

The first point to mention here is that probiotics are a natural supplement and not a medicine. They can be used to support general health, as part of a healthy lifestyle - rather than as a quick fix or course. Fermented foods have been part of the traditional diets of many different ethnic groups for centuries. Using foods such as sauerkraut, kimchi, kefir and kombucha people have been consuming probiotics for generations, but it has only been more recently that we have been able to consume them in an easy-to-take capsule form.

But why take them on an ongoing basis?


So, whilst you might think that once you have established good gut flora that it can then be left to its own devices, in reality our lifestyles are now so challenging for our microbiome that many of us need to nurture it on an ongoing basis.

Most people know that antibiotics do not differentiate between the good and bad bacteria in our guts, and therefore negatively impact on our probiotic colonies, but we often do not look at all the different sources of antibiotics in our food chain. Not only are we exposed to antibiotics when we take them ourselves, but we are exposed to low levels all the time if we eat non-organic meat and dairy produce. These have a similarly negative impact on our gut flora.


Other factors that deplete our flora include, over-consumption of sugar, contraceptive pills, HRT medication and stress. With all of these things in mind it is easy to see why a daily top-up of probiotics might be a good idea for many people. Like most vitamins and minerals, we do not produce probiotics ourselves.

Many every day factors, including chlorine in tap water, can affect our gut bacteria

What does the research say?

In the majority of studies that investigate the effects of taking probiotics, researchers administer a daily dose to participants, for example this study from 20041, indicating an advantage to taking them every day.

In another, small study2 10 women were allocated to either a probiotic or control group to investigate whether Lactobacillus rhamnosus GR-1 and Lactobacillus reuteri RC-14 could colonise in the vagina. The women took either the probiotic or placebo supplement orally for 14 days, and follow-up faecal and vaginal swabs were collected on day 0, 7, 14 and 21. It was found that the strains were able to colonise in the vaginal region after day 7 and 14, but that once the probiotic intake stopped at day 14, neither strain was detected after a further week (at day 21). These findings indicate the need to take a probiotic supplement daily in order for them to colonise and exert their health benefits, and that if you stop taking them, the probiotics will 'exit' the body within a week.

A further study3 looked at the ability of Lactobacillus rhamnosus LGG® to survive and reach the colon alive, and also its longevity once in the gut. 76 volunteers took the probiotic every day, either freeze-dried or in the form of fermented milk. L. rhamnosus LGG® was recovered in all of the faecal samples from those who were given the fermented milk form, and in 86% of samples from those who were given the freeze-dried form. Once the participants stopped taking the strain, it was found that after 4 days, L. rhamnosus LGG® was present in 87% of the individuals' stools, but after a week, this number dropped to 33%. These findings too support the idea that once probiotic consumption has ceased, the probiotics are unlikely to remain in the gut for more than a week.

Finally, in a double-blind, randomised crossover study4 of 12 volunteers, either a probiotic mixture or placebo was administered to investigate the ability of Lactobacilli strains to colonise in humans. Of 47 potential strains screened, 5 were selected for this trial. For the first 18 days, the participants were given either a mixture of 2 probiotic strains, a mixture of 3 probiotic strains, or a placebo. After this time, the probiotic dose was stopped for 17 days. This was repeated in three further cycles of 35 days (18 days taking the probiotics, with a 17-day washout period). Faecal samples were collected on days 0, 18, 23 and 29 of each cycle, and it was discovered that most of the strains were isolated in the samples from day 18, but at by day 23, only 2 strains were isolated (from 3 faecal samples), and by day 29 there were no strains isolated. Therefore, after probiotic supplementation was stopped, most strains disappeared after 5 days, and all of the strains disappeared after 11 days. Though it was expected that not all of the 5 strains would survive in humans, as this trial was only testing potential probiotics, this does again reinforce the notion that daily probiotic supplementation is most beneficial for colonisation.

Can we overdose or become ‘dependent’ on them?

One concern people often have is whether their digestive system will become ‘lazy’ if they take probiotics every day. But, rest assured, probiotics are not thought to be like laxatives which can cause the gut to become 'lazy' and reliant on them in order to function. There is no current research to suggest the body becomes dependent on probiotics.

Healthcare practitioners can read more on the subject of long-term use of probiotics, and whether that can lead to dependency, in the following FAQ: 'Is there a risk of dependency when taking probiotics?'

In regards to overdosing, even when taken on a daily basis and at high doses it is extremely difficult to overdose on probiotics. For more on this subject you may like to read our FAQ; 'Is it possible to overdose on probiotics?'

The idea that taking too many probiotics can make your gut 'lazy' is a myth

When should someone NOT take probiotics?

Probiotics are some of the safest natural supplements available, and have very few contraindications. There are a few groups of people who it is recommend exercise a degree of caution when they are considering supplementation with live cultures, an example of which is people who are immune-supressed (or taking immune suppressive medication), and people with dark blood in their stools. Under these circumstances, it would be wise to seek the advice of a GP before considering probiotic supplementation. In fact if ever in doubt, always speak to your doctor about any health supplements. For more information see this contraindications FAQ.

With regards to medications and natural remedies, there are no known contraindications. The only point to take in to account here is if a supplement has antibacterial or anti-fungal properties. If it does, like garlic for example, then it is recommended that you take the probiotic at least a couple of hours either side of the other supplement, so as not to damage the bacteria. But with regards to safety, probiotics can be taken alongside all natural remedies without any problem.

In conclusion

Many people feel that probiotics give them that extra bit of confidence and a little health boost. Due to unfavourable lifestyle factors that compromise our gut flora it may well be better to replenish our probiotic colonies on an ongoing basis, and this is why many people choose to take probiotics every day.


1. Mimura, T. et al. (2004). 'Once daily high dose probiotic therapy (VSL#3) for maintaining remission in recurrent or refractory pouchitis'. Gut, 53(1): 108-114

2. Morelli L et al., 2004. 'Utilisation of the intestinal tract as a delivery system for urogenital probiotics'. Journal of clinical gastroenterology; 38(6): 107-110

3. Goldin BR et al., 1992. 'Survival of Lactobacillus species (strain GG) in human gastrointestinal tract'. Digestive diseases and sciences; 37 (8): 121-1218

4. Jacobsen et al., 1999. 'Screening of probiotic activities of 47 strains of Lactobacillus spp. by in vitro techniques and evaluation of the colonisation ability of 5 selected strains in humans'. Applied and Environmental Microbiology; 65 (11): 4949-4956

Image references:

This FAQ has been answered by Kathy Wheddon, Nutritional Therapist DipION.