Theralac is a probiotic supplement marketed by Master Supplements, Inc. containing at least 30 billion CFU per capsule from 5 strains of bacteria and 2 prebiotics. It is stated to work “best for diarrhea, occasional constipation, restoring digestive regularity, immune system regulation and nutrient absorption.”
This supplement has 17 CFU of 3 Lactobacillus strains and 13 billion CFU of Bifidobacterium strains at expiration. It is packaged with 40+ billion CFU. According to Master Supplements, Inc., all strains are able to attach to the lining of the intestines.
The five probiotic strains are:
At the time of this writing, the other ingredients are: microcrystalline cellulose, sodium alginate, hydroxypropyl methyl cellulose (capsule shell), tri-sodium phosphate, magnesium stearate, silicon dioxide, calcium silicate, ascorbic acid, LactoStim (sunflower lecithin + oleic acid).
Please always read ingredient labels as formulations can change over time!
This probiotic supplement is promoted to help:
You will have to find the Goldilocks routine that works for you, but I personally think that taking only 2 capsules per week will not be often enough to sustain consistent benefits for most people.
It has some very good reviews on Amazon.com:
"I suffer from IBS (Irritable Bowel Syndrome). Since I started taking Theralac my IBS episodes are very manageable. I most recently ran out of this and was miserable. Within a week, I felt better and have less digestive problems and stomach cramping. It really works."
"I swear by this product. It has completely transformed my stomach when doctors could not figure out what was wrong or provide any help. I had a constantly upset stomach before taking Theralac and now I do not have any problems. I continue to take it and plan to take it indefinitely."
"I was on strong antibiotics and needed something to restore my gut health and mental health after getting off of them. This did the trick, took about a few months to feel normal again mentally and physically - more definitely needs to be known about bacteria in the gut and how it affects us daily - its so important! Anyways, this probiotic is one of the best!"
I don’t have any major complaints against this supplement as much as I do against the marketing of this product. This review was very, very time-intensive because of the conflicting information I found. This is not unusual, unfortunately, as many manufacturers reference studies that do not directly apply to their products.
Studies that are referenced used some of Theralac’s strains or none of them. Since effects are usually strain-specific, especially when stimulating the immune system, the results of the referenced studies may or may not apply to Theralac’s strains.
I realize that most people will not go through the intense analysis I did but for public-relations purposes it would be helpful if the referenced information directly supported the product.
This supplement is marketed to be “best for diarrhea, occasional constipation, restoring digestive regularity, immune system regulation and nutrient absorption”, but none of the studies that are referenced, with the exception of some immune regulation studies, directly support that statement. Granted, Bifidobacterium and Lactobacillus species generally help with those issues, and this supplement probably can fulfill those statements, but it would have been nice to have the documentation in one place for someone like me to review for someone like you.
No studies with this product as a whole were performed. Note that this is not unusual, however. Very few multi-species probiotic supplements are used in studies. Instead, species/strains that are shown to be effective and non-competing are mixed together in most multi-species supplements such as this one.
This, to me, is the information that I found most annoying: Most of the studies Theralac referenced in their “Special Report” show that a daily dose of 1-3 capsules is required for the desired outcomes of the studies. This contradicts what they say in their “Price per Week” comparison saying that the first bottle will last 10 weeks and the second bottle will last 15 weeks because those numbers are based on 1 capsule per day for the first 2 weeks and then 2 capsules per week thereafter. Of course individual results will vary, but do not base your decision solely on the stated price-per-week. Remember what I said about the Goldilocks routine.
Note that I did contact Master Supplements once the page was published to get their opinion on my concerns. They were very kind to have contacted me. I will update this information once I receive clarifications.
If you have any information on this, please share!
In the US from: Amazon.com
In Canada from: Amazon Canada
In the UK from: Amazon UKOR nearly world-wide at
There is also the powdered formula (Granular") available nearly world-wide at Vitacost:
(click on image-note that Vitacost has not updated the image)
Despite the mixed messages from the marketing, it is a high potency supplement, has "safe" species of Lactobacillus and Bifidobacterium, has a nice delivery system, has a nice third-party verification that consumers can check, is free of most allergens and is packaged securely.
If you would like help with your choices in probiotics, dietary and lifestyle advice, nutrition consultations may be for you.
Thanks to Susan for suggesting a review of this supplement!
If you decide to take this supplement, I would combine the health benefits of it with the benefits provided by:
To read about my approach to supplement reviews, and about my reviews of other probiotic supplements, click here.
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