What to Actually Look for in a Probiotic
(Most of What You Have Been Told Is Wrong)

I took probiotics for years and felt absolutely nothing. I would buy whatever the pharmacist suggested, take them for two or three weeks, and then quietly stop when nothing changed. I assumed I was one of those people probiotics just did not work for.

Then I started actually researching them. Not the label on the bottle, but the peer-reviewed research on how probiotics survive the journey through your body and what makes one product meaningfully different from another. What I found explained everything. I had not been buying bad luck. I had been buying products that were not designed to work the way I needed them to.

If you have ever tried a probiotic and felt nothing, this is worth reading.

The CFU Number Is Not What You Think

The first thing most of us look at on a probiotic label is the CFU count. Colony forming units. It sounds scientific and more is obviously better, right?

Not exactly. CFUs measure how many live bacteria are in the capsule at the time it is manufactured. What that number does not tell you is how many of those bacteria survive the trip through your stomach acid and actually reach your intestines alive.

Research on probiotic survivability consistently shows that unprotected probiotic bacteria can lose the vast majority of their viability when exposed to gastric acid. A 2024 study published in Nutrients used SHIME technology to compare four commercially available probiotic formulations and found that delayed-release, acid-resistant capsules produced meaningfully higher bacterial survival rates than standard unprotected capsules during upper gastrointestinal transit.

The question to ask is not how many CFUs does this contain. The question is how many CFUs actually reach my intestines alive. Those are two very different numbers depending entirely on how the product is formulated.

You Do Not Need to Take a Break from Your Probiotic

This one comes up constantly and it is one of those pieces of wellness advice that has been repeated so many times it sounds like fact. The idea is that you should take probiotics for a few weeks, then stop to prevent your gut from becoming dependent on the supplemented bacteria.

The concern behind this advice is not completely unreasonable. But the research does not support taking breaks as a general practice. A 2023 meta-analysis in Food Science and Nutrition found that long-term probiotic use of eight weeks or more produced meaningful benefits for blood pressure, immune function, and metabolic health. When you stop, those benefits fade over time because the supplemented strains do not permanently colonize your microbiome.

Think of it less like a course of antibiotics and more like eating fermented foods. You would not take a two-week break from yogurt to prevent your gut from getting too comfortable with it. Daily, consistent support is the point.

Strain Diversity Matters More Than You Realize

Your gut alone contains hundreds of different bacterial species. Your microbiome is not a monoculture. It is an enormously diverse ecosystem, and that diversity is what makes it resilient.

Many probiotics contain one or two strains of bacteria. A single-strain supplement is better than nothing, but it is a narrow intervention in a very complex system. Research specifically on menopause and the gut microbiome shows that estrogen decline reduces microbial diversity, and that this reduced diversity is linked to worsening menopausal symptoms including weight gain, bone health changes, and cognitive shifts. A 2025 review published in a SAGE journal found that probiotics such as Lactobacillus strains have been shown to increase bacterial diversity and improve metabolic and overall health in women during menopause.

More diverse microbiomes are more capable of managing inflammation, processing hormones, supporting immune function, and producing the neurotransmitters that affect mood. A probiotic with a single strain is not going to address that meaningfully.

What to Actually Look For

Here is the checklist I now use when evaluating a probiotic. These are the things that actually make a difference based on what the research shows:

What I Personally Take

After doing all of this research, I switched to doTERRA PB Restore. I want to be straightforward about this: I share it because I use it every single day and I noticed a real difference, particularly with my IBS symptoms, which improved within the first two weeks in a way that nothing else had managed in years.

It checks every item on the list above. It contains 30 pre-, pro-, and postbiotics plus bacteriophages, with 18 billion CFUs across 24 active cultures from 22 different species. The dual-chamber, time-released capsule releases the bacteria throughout the day rather than all at once in the stomach. And it is formulated with whole-body microbiome health in mind, not just gut function.

It is also worth mentioning: the first week or two, you may notice some digestive changes. This is normal and it is a sign the product is doing something. It settled down quickly for me. Take it before a meal with water and avoid anything very hot when you take it.

You can find it on my supplement page at paulawatt.com/menopause-supplements.

If you want to understand why your gut health has such a profound effect on your hormonal symptoms during menopause, my article on the gut-hormone connection goes into the full picture. And if you want to understand why fiber is the other half of this equation, that is covered in why fiber and probiotics belong together.