Probiotics : What You Need to Know Before Buying


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I think if you talk to most dietitians, we will all tell you the same thing - EAT first, SUPPLEMENT second. A well-balanced diet should provide you with all the nutrients your body needs. However, sometimes our bodies are compromised or we find our diets lacking certain nutrients and may benefit from a supplement. Unfortunately, buying probiotics can be extremely intimidating - even for someone with a nutrition background! Below, I am sharing what you need to know before you start shopping. 

Deciphering the Probiotics Label


This stands for colony forming units and is essentially a measure of how many bacteria you are getting in a dose.  Look for one that contains at least 108 to 109 CFUs/mL (100 million to 1 billion CFUs/mL) if taking for general health purposes. If taking one therapeutically for a specific condition, you may want to consider finding one around 7 to 9 billion CFUs/mL.

Outside Safety Guarantee

Look for a supplement that has a approval from one of the major testing companies like ConsumerLab or USP. This means the product has been tested by an outside company and evaluated to be safe and contains what its label suggests. This is important because probiotics fall in that gray area of FDA regulation like other diet supplements which means that there is no oversight of their manufacturing or safety and/or may or may not contain exactlywhat is listed on the label. While it doesn’t guarantee a safer product, seeing a ConsumerLab or USPstamp on the label is usually a good sign and a better place to invest money than one without it. 

Expiration Date 

Bacteria are living microbes, so they don’t live forever – and they don’t live if not stored properly! Purchase one that you could use up well before the expiration date, and skip larger quantities. 


Always check the storage directions and follow them since some require refrigeration. Also, make sure that the retailer has been storing them correctly before purchasing. 


Each probiotic supplement is going to be slightly to very different from the others on the shelf. Most bacteria strains are either going to be from the Bifidobacteria or Lactobacillus species. The word following the species name indicates the strain. Here’s an example: 

  • Lactobacillus plantarum 299v, 
    • Lactobacillusis the genus, plantarumis the species, 299v is the strain. You may also see this listed as plantarum 299v. 

Specific Strains

While our knowledge is still evolving, it appears specific strains are more effective for different ailments. You want to make sure you choose one that has microbes to support your health needs by looking at the bacteria strains and species listed on packaging. Usually a mix of strains is recommended (as opposed to just one strain). Check out this online tool that will sort probiotics on the market by health issue.


Lastly, consult with a doctor before giving probiotics to individuals with compromised immune systems or not fully developed immune systems such as infants and children. Also, if you have negative side effects associated with taking probiotic may mean you need a different strain. 

What are your favorite OTC probiotics?