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Hum Nutrition is one of the more popular supplement brands in the US, unsurprisingly considering the brand’s selling points— formulations made by a team of RD nutritionists, triple-tested for purity and potency, verified clean, and they’ve got a creative naming sense— think Flatter Me, Skinny Bird, or Private Party.
As one of their more popular formulas, Gut Instinct is purported to improve gut health and boost immunity with its 10-strain probiotic blend.
But is there any clinical evidence to suggest that the probiotic strains in Gut Instinct definitively improve gut health? Does it contain any questionable additives, despite being ‘verified clean’? And how do real users rate and describe the effects of Gut Instinct?
In this article, I’ll be answering all of these questions and more as we analyze the ingredients in Gut Instinct. We will also review relevant medical research to give our take on whether it’s likely to be effective or if it’s all marketing.
Main Takeaways
- Gut Instinct has probiotic strains that have been shown, in convincing scientific studies, to benefit gut health, particularly in preventing and treating gastrointestinal diseases.
- There are also preliminary studies that showcase the skin and psychological benefits of some of the probiotics present in Gut Instinct.
- Some of the studies, particularly those that do not directly address gut health, appear to be flawed for several reasons, such as low sample size, short duration, and lack of diversity, among others.
- Customer reviews are mostly positive, but there are also many people that claim to have experienced no benefits.
Analyzing The Label
Let me start by mentioning something important — Hum Nutrition uses proprietary blends, making it difficult to fully assess the efficacy of Gut Instinct.
Proprietary blends
This term refers to the practice where supplement manufacturers list multiple ingredients under a single total quantity, instead of specifying the exact amounts of each ingredient.
This is not-so-good for a few reasons:
Consumers cannot know the precise amount of each ingredient in a proprietary blend. This makes it hard to gauge the potential effectiveness of the supplement, and it’s even harder to compare products.
Companies can also take advantage of proprietary blends to obscure the fact that beneficial ingredients are included in negligible amounts, while fillers or cheaper ingredients make up the bulk of the blend.
Some ingredients might interact with medications or have potential side effects at certain doses. Without knowing the exact amounts, it’s hard for consumers and health professionals to assess potential risks.
For people tracking their intake of certain nutrients or compounds, proprietary blends make it impossible to accurately count what’s being consumed
However, transparency is always preferred as it’s the only way for someone to know whether or not a product is likely to work without trying the product.
Breaking down the probiotics
Before we break down the science behind each bacterium in Gut Instinct, I think it’s important to assess whether probiotics, in general, are beneficial for gut health and related gastrointestinal diseases.
In a meta-analysis containing 74 studies, 84 trials, and 10,351 patients, the authors concluded that, in general, probiotics are beneficial in the treatment and prevention of gastrointestinal diseases.
Curiously, they found that probiotics had a positive effect on treating or preventing eight types of diseases including Pouchitis, Infectious diarrhea, Irritable Bowel Syndrome, Helicobacter pylori, Clostridium difficile Disease, and Antibiotic-Associated Diarrhea.
They also found that most types of probiotics they studied were effective, except for Lactobacillus acidophilus, Lactobacillus plantarum, and Bifidobacterium infantis.
Two of the aforementioned probiotics are present in Gut Instinct, albeit it’s also possible to find strong evidence in their favor, as we’ll see.
In conclusion, probiotics are beneficial for gut health, but the challenge lies in identifying the strains that work.
Now, let’s break down each probiotic strain in Gut Instinct.
Lactobacillus acidophilus
Gut Instinct contains 10 probiotic strains within their single blend, and looking at the order by which they’re listed, lactobacillus acidophilus is the highest-dosed one.
A 2022 study analysis published in the Journal of Microbiology and Biotechnology acknowledges L. acidophilus as having various health benefits, including the improvement of gastrointestinal health via:
– Maintaining a healthy ratio of “good” to “bad” bacteria in the gut, which is crucial for optimal digestive function and overall gut health.
– Inhibiting the growth and proliferation of harmful microbes by competing for resources and attachment sites in the gut.
– Potentially enhancing the integrity of the gut barrier, thus reducing the risk of harmful substances or bacteria leaking into the bloodstream (a phenomenon known as “leaky gut”).
– Stimulating the immune response in the gut, enhancing the body’s defenses against potential infections and diseases.
Bifidobacterium lactis UABla-12
The second highest-dosed strain is bifidobacterium lactis UABla-12.
It has been shown in a 2020 randomized control trial (with primarily young to middle-aged adults and a normal to overweight BMI) to improve symptoms of IBS.
The strain reduced abdominal pain severity over the six-week intervention period compared to placebo.
And for patients experiencing constipation or diarrhea, symptoms commonly associated with IBS, the strain also helped normalize bowel movements.
Lactobacillus plantarum
Hum Nutrition claims that Lactobacillus plantarum, the third highest-dosed strain, can “support skin hydration and shield the skin against free radicals”.
A clinical trial involving 110 volunteers aged between 41 and 59 years with dry skin and wrinkles found that subjects taking L. plantarum experienced significant improvements in skin hydration compared to placebo.
The probiotic group also showed significant reductions in wrinkle depth and improvements in skin gloss and skin elasticity.
Bifidobacterium longum
Coming next is Bifidobacterium longum; a bacterium that is native to the human gastrointestinal tract but may be lacking in individuals with intestinal diseases.
A review article published in the Journal of Immunology Research suggests that B. longum may be used in the prevention and treatment of IBD.
Lactobacillus rhamnosus
A lesser-known bacterium is Lactobacillus rhamnosus.
A clinical study showcases how L.rhamnosus may help reverse the learning and memory-impairing effects of lead in rats.
Animal tests are generally considered low-quality studies, so albeit promising, do take this with a grain of salt.
Nonetheless, it’s interesting to observe the relationship between the gut and the brain, and how probiotics may play a role in both the physical and mental realms.
Streptococcus thermophilus
I wouldn’t be surprised if you knew about S. thermophilus given its common use in fermented dairy goods such as yogurt.
A research analysis featured in PLOS ONE proposes that S. thermophilus may have a beneficial impact on the immune system’s health.
This inference was based on findings that revealed changes in specific immune-related genes when peripheral blood mononuclear cells (PBMC) were introduced to live S. thermophilus 285 bacteria.
S. thermophilus 285 demonstrated anti-inflammatory and immune-modulating properties, with the potential to alter the expression of diverse genes tied to the body’s immune responses.
In other words, it has the potential to aid the body in its response against infections and disease.
Lactobacillus paracasei
Another bacterium that is also added to yogurt is L. paracasei, so what do researchers know about it?
A meta-analysis studied the effects of consuming a Fermented Dairy Drink (FDD) containing L. paracasei on Common Inflammatory Diseases (CIDs).
According to the author, FDDs containing L. paracasei may reduce the incidence of chronic inflammatory diseases (CIDs) in the general population.
However, the author also highlights the difficulties of conducting and interpreting these types of studies, especially concerning immune function outcomes.
Bifidobacterium breve
Hum Nutrition claims that B. breve may be able to support skin elasticity and hydration, but I couldn’t find any compelling studies, apart from a small mice study.
However, I found a few different studies claiming that B. breve may potentially have cognitive effects.
In this double-blind, placebo-controlled trial, 80 older adults with Mild Cognitive Impairment were randomly assigned to take either a probiotic or a placebo once daily for 16 weeks.
The study found that, overall, the group that received B. breve showed an improvement in their cognitive functions, particularly in immediate memory, visuospatial/constructional ability, and delayed memory.
In another randomized controlled trial, 45 patients diagnosed with major depressive disorder (MDD) were randomly divided into two groups: those who received the probiotic and those who received a placebo.
The results showed that the group taking B. breve demonstrated a more significant reduction in depression symptoms than the placebo group.
At the same time, these studies are flawed in the sense that both have a small sample size, and only have a brief duration, plus the participant pool is not diverse enough.
Lactobacillus salivarius
A randomized controlled trial conducted with healthy subjects demonstrated that consuming probiotics like L. salivarius leads to a decrease in inflammatory markers such as total cholesterol, LDL cholesterol, and triglycerides inflammatory, particularly when combined with prebiotics.
In other words, the study defends that probiotics, either alone or combined with prebiotics, can help reduce inflammation and improve insulin resistance, potentially aiding in the prevention and treatment of metabolic disorders.
However, it’s important to note that the study does have some limitations, namely the short intervention period, the lack of a “prebiotic” group only, and not being able to study the precise molecular mechanisms involved.
Lactobacillus casei
A study published in the American Society for Microbiology Journal investigating the effects of L. casei on the immune response of mice suggests that the main immune cells activated after oral L. casei administration are those of the innate immune response, which is our first line of defense against germs.
However, as I’ve said before, animal studies are typically considered low-quality evidence, so be a bit skeptical about what’s being purported here.
Given all this information we’ve just covered, I’m led to believe that probiotics can benefit our gut health, and potentially help prevent and treat certain gut conditions.
Any Questionable Ingredients?
My preference leans towards assessing ingredient safety based on the European Union’s standards.
The rationale behind this choice is rooted in the fact that the EU maintains stricter regulations compared to the US.
This strictness is reflected in the process where the European Food Safety Authority (EFSA) is required to scrutinize any dietary supplement for safety and efficacy before it’s allowed to enter the market.
On the other hand, the US system places the onus on manufacturers to ensure the safety and label accuracy of their products. In this system, the Food and Drug Administration (FDA) largely intervenes when there’s a report of an issue with a product that’s already on the market.
Therefore, the regulatory rigor of the EU provides a stronger assurance of ingredient safety in my eyes.
With that being said, all of the ingredients listed on Gut Instinct’s label are recognized as safe in the EU, so you shouldn’t worry.
What Do Real Users Have To Say?
Keiko Beauty, a Youtube creator, reviewed her experience with Gut Instinct:
Here’a a pretty balanced review of Gut Instinct by a Youtube channel called Probiotics Guide:
I’ve also gathered some written reviews from third-party websites, as that’s one of the best ways to make sure you’re reading credible, real experiences.
For instance, Gut Instinct has over 900 reviews on Amazon with a final score of 4.2/5 stars, which is not that impressive, but let’s look at some of the reviews anyway.
“Lost over 40 pounds but couldn’t get my stomach smaller. I was just losing weight everywhere else. I am limited to how much exercise because of an injury. There was all kinds of options on probiotics and digestion products. I mean where to start. And the money. Others might like to gamble with their money and take a chance on a product. I don’t trust a sales person anywhere. A couple liars make them all look bad to me.
The price was fair on the Hum Gut Instinct. And I lost another 15 pounds in the stomach area. Dropped 2 pant sizes almost 3. No I didn’t spend all day in the bathroom. Actually I am more regular now than before.” – Jerry Windisch
“I have always had an issue with “eliminating” and chronic constipation. Its been frustrating but this HUM Gut probiotic has worked well. I gave it a try for a month and I’m pleased. The directions say to take it on an empty stomach ( I take it first thing in the morning). Then do not eat or drink anything but water for 30 minutes (this is not in the directions but my little research said mentioned to allow 30 minutes for the probiotic to move through your system). Then I proceed through my day. Nice good, smooth moves throughout the day (no diarrhea just nice cleansing poop). I feel great and happier.” – DaByzBee
“Everyone is different but this didn’t help me in fact it made my stomach upset, constipated, and gassy.” – A. Warren
“The first few days I didn’t notice too much of a difference but boy oh boy did I notice it on the 3rd day on. I had cramps pretty hard and very loose stools. I think it is because of how potent it is. I am no longer bloated and just a little gassy. I have heard others say that it takes some time for the side effects to diminish – I think it’s a good product and am looking forward to less side effects.” – Dawnmarie
Conclusion
Gut Instinct is likely to improve gut health both in healthy individuals and those with conditions like IBS.
It’s also unlikely for Gut Instinct to cause side effects (since it has no harmful additives), even though a few users did feel bloated.
However, most verified customer reviews are positive, and there are many people that stand by Hum Nutrition as a legitimate brand.
Editor’s note: The content on this website is meant to be informative in nature, but it should not be taken as medical advice. The content of our articles is not intended for use as diagnosis, prevention, and/or treatment of health problems. It’s always best to speak with your doctor or a certified medical professional before making any changes to your lifestyle, diet, or exercise routine, or trying a new supplement.
