Bio Complete 3 is a gut health supplement manufactured by a brand called Gundry MD. The company claims their product has prebiotic, probiotic and post-biotic ingredients to support optimal gut function, and that this ingredient blend can improve energy levels and reduce cravings.

But does Bio Complete 3 proven to enhance gut function? Does it contain any unhealthy ingredients? Will it cause side effects? And is Bio Complete 3 better or worse than other popular gut health supplements like Seed probiotic?

In this article we'll answer all of these questions and more, as we analyze the ingredients in Bio Complete 3 to give our take on whether or not the supplement is likely to be effective for improving gut health, and whether or not it's healthy.

We'll also discuss the risk of side effects, and compare Bio Complete 3 to other popular gut health supplements to pick our winners (and losers).

Key takeaways:

• Updated formulation is improved
• Contains a complex with unclear ingredients
• We do not currently recommend Bio Complete 3

Ingredient Analysis

The active ingredients in Bio Complete 3 are shown below:

CoreBiome is included in two of the blends.

This complex is manufactured by a company called Compound Solutions, and we can't find the full list of ingredients in CoreBiome on its manufacturer's product page.

SunFiber is the prebiotic ingredient, and prebiotics are a class of compounds that can help to feed the healthy bacteria in the gut.

This patented type of fiber, derived from guar gum, may be significantly underdosed in Bio Complete 3.

A medical review on SunFiber published in the Journal of Clinical Biochemistry and Nutrition recommended a minimum dietary fiber intake of 20,000 milligrams (mg) daily. Bio Complete 3 provides around 200 mg, or 1% of the recommended minimum amount.

We cannot identify any clinical studies suggesting that 200 mg of SunFiber has any health benefits, nor does Gundry MD currently cite any on their product page.

Bacillus coagulans is a probiotic species that's clinically shown to relieve gas and bloating, as we documented in our review of BelliWelli powder.

Bifidobacterium bifidum is a probiotic species that may have beneficial effects on cholesterol levels, as documented in a 2019 clinical trial.

The inactive ingredients in Bio Complete 3, shown below, should be safe and non-toxic:

Overall, we consider Bio Complete 3 potentially effective for supporting gut health, given the inclusion of two research-backed probiotic species.

We do not currently recommend this supplement due to our inability to access CoreBiome's full ingredient list.

There's a theme of underdosed ingredients in Gundry MD supplements that we've reviewed, as we documented in our Total Restore reviews article (another Gundry MD product). 

Does Bio Complete 3 Cause Side Effects?

Bio Complete 3 does not appear to have been studied in any clinical trials, so it's impossible to say for certain whether or not the supplement causes side effects.

However, we can make an educated guess based on its ingredients.

The only ingredient in this formulation that we consider potentially likely to cause side effects is the probiotic blend ProDura, because probiotics at high doses can cause gastrointestinal distress like bloating and indigestion.

Unfortunately, because Gundry MD lists the dose of this ingredient in mg instead of colony-forming units (CFU), which is the standard for probiotics, we cannot determine if this ingredient has a high dose or not.

One good thing about this supplement is that it's free of questionable added ingredients like added sugar or artificial food dye.

Overall we do not consider Bio Complete 3 likely to cause side effects in healthy adults, but we urge Gundry MD to publish the dose of the probiotic ingredient in CFU, and to explain the ingredient blend in CoreBiome, so that consumers (and researchers like us) can make a more informed determination.

Questionable Health Claims

There are a number of questionable health claims on the Bio Complete 3 product page, as shown below:

The brand claims that their supplement can replace fatigue with a feeling of youth and energy, can improve digestion and can reduce cravings for unhealthy foods.

None of these claims are medically cited, and the asterisk at the end of each claim simply corresponds to a notice that "Every individual is unique."

We recommend that consumers entirely disregard health claims made by brands that provide no proof of such claims, and we urge Gundry MD to either provide evidence supporting these claims or remove them from their website.

Bio Complete 3 vs. Popular Gut Health Supps

Here's how Bio Complete 3 compares to other popular gut health supplements in terms of potential effectiveness and healthiness, in our opinion:

Seed Probiotic

Contains a probiotic strain which is clinically shown to stabilize the gut microbiome and support immune function.

One of the industry leaders in gut health supplements, and a much higher-quality formulation.

Winner: Seed

Synogut

Weaker formulation than Bio Complete 3. Also there was an ingredient discrepancy between the brand's website and Amazon listing upon our last analysis.

Synogut is a ClickBank product, and as we explained in our Synogut review article, we currently recommend avoiding all ClickBank products.

Winner: Bio Complete 3

Benefiber

Only contains one ingredient (wheat dextrin), which is a form of soluble fiber which can help support optimal gut function.

Winner: Benefiber

Our Clean Gut Health Picks

Manukora MGO 850+ is our top whole food gut health pick.

A 2024 clinical trial reported that manuka honey ingestion "correlates with beneficial modulation of gut microbiota composition."

MBG Organic Fiber Potency+ is our top gut health supplement.

MBG Organic Fiber Potency+ contains 100% soluble fiber, which was described as "one of the most important nutrients for the gut microbiota" in a clinical review published in the Molecules journal.

Both of the products recommended in this section are free of ingredients that we consider to be unhealthy.

Bio Complete 3 Pros and Cons

Pros:

• Contains some research-backed active ingredients
• Unlikely to cause side effects
• No unhealthy inactive ingredients
• No unsafe active ingredients

Cons:

• Active ingredients may be underdosed
• Questionable health claims on brand's website
• Doesn't appear to be clinically tested
• No test results on product page

Conclusion

We do not recommend Bio Complete 3, and we do not consider the supplement likely to improve gut function.

We reviewed clinical studies on each of the three active ingredients, and were unable to identify any evidence that these ingredients are effective for enhancing gut health at the doses included in this supplement.

There are no ingredients in Bio Complete 3 that we consider dangerous or likely to cause side effects.

Gundry MD makes a number of uncited health claims on the Bio Complete 3 product page, and we urge the brand to either provide medical evidence of these claims or remove them from the website.

We consider Bio Complete 3 to be a higher-quality gut health supplement than Synogut, but a less effective option than Seed or Benefiber.