Synbiotic 365 Review: Benefits, Effectiveness, Side Effects, Cost

By Derek Lakin
HighYa Staff
Published on: Sep 18, 2018

United Naturals advertises Synbiotic 365 as an advanced formula consisting of beneficial probiotic strains and prebiotic ingredients, that when combined, can deliver lasting relief from bloat and other embarrassing digestive issues.

Based on the available clinical evidence, can you realistically expect to experience benefits like these? Furthermore, is there supporting data that taking a combination product like Synbiotic 365 will deliver better results than a standalone probiotic supplement?

In this brief article, we’ll discuss the formula’s ingredients, pricing, and competition, all aimed at helping you make an informed decision. Before diving in, though, let’s clarify what we’re talking about.

What Is a Synbiotic Supplement?

Probiotics are specific bacteria strains that, when taken regularly as a dietary supplement, have been clinically shown to provide a wide variety of digestion-related benefits, in addition to boosting immune function.

Prebiotics, on the other hand, are certain ingredients that these bacteria use as an energy source upon arriving in your digestive tract.

With these details in mind, ScienceDirect explains, whether referencing Synbiotic 365 or another formula, “Synbiotics are a combination of prebiotics and probiotics that are believed to have a synergistic effect by inhibiting the growth of pathogenic bacteria and enhancing the growth of beneficial organisms.”

Writing for Health.com, Anthea Levi tells us “the idea behind synbiotics is that adding prebiotics to a probiotic supplement can help ensure that the digestion-friendly microorganisms arrive in the gut alive and well. These supplements are said to be particularly useful for people with conditions like IBS, other bowel disorders, and diabetes.”

Cynthia Sass, RD, Health contributing nutrition editor, adds that when combined with probiotics, prebiotics can “also increase nutrient absorption and support bowel regularity.”

Taking a Closer Look at Synbiotic 365’s Ingredients

According to the supplement facts label listed on the United Naturals website, Synbiotic 365 contains:

  • Vitamin B1 2.4 mg
  • Vitamin B2 2.6 mg
  • Vitamin B3 32 mg
  • Vitamin B6 3.4 mg
  • Vitamin B9 800 mcg (480 mcg folic acid)
  • Vitamin B12 4.8 mcg
  • Vitamin B7 60 mcg
  • Vitamin B5 10 mg
  • Probiotic Blend 30 billion CFU – Lactobacillus acidophilus La-14, Bifidobacterium lactis Bl-04, Lactobacillus paracasei Lpc-37, Lactobacillus plantarum LP-115, Streptococcus thermophilus ST-21, Lactobacillus casei LC-11, Lactobacillus reuteri, Lactobacillus salivarius LS-33, Lactobacillus rhamnosus LR-32, Bifidobacterium bifidum BB-06, Bifidobacterium longum BL-05, Saccharomyces boulardii
  • Chicory Root Inulin 300 mg

Sites like WebMD, the Natural Medicines Database, and Examine.com report that the first eight vitamins in this formula are essential for maintaining human health. For example, B1 (thiamine) is essential in the breakdown of carbohydrates, B2 also helps digest carbs, as well as proteins and fats, while Healthline tells us that every part of your body needs B3 (niacin) to function correctly.

However, they also report that unless someone’s deficient in these vitamins, supplementing them likely won’t deliver meaningful health benefits.

» Related: Do You Need to Take Vitamins or Dietary Supplements?

Probiotic bacteria are identified by their genus (e.g., Lactobacillus), which is like an extended family; their species (e.g., acidophilus), and their strain (La-14).

Lactobacillus acidophilus (whether contained in Synbiotic 365 or another supplement) was the first probiotic strain widely used, which seems to work especially well for irritable bowel syndrome (IBS) symptoms and urinary tract infections in children.

Among others, paracasei may relieve allergic symptoms and decrease skin sensitivity, plantarum produces its own antibiotics, casei may improve allergy symptoms and reduce cholesterol (along with reuteri), and rhamnosus has even been shown to help obese women lose weight.

In the Bifidobacteria genus, lactis may reduce inflammation and aid in the management of diabetes, bifidum shows promise for addressing constipation and lung infections, and longum may also be effective for constipation and airway infections, in addition to IBS and ulcerative colitis.

Finally, Streptococcus thermophilus could decrease the chances of kidney stones and increase anti-tumor activity, while Saccharomyces boulardii seems to be especially useful for addressing different causes of diarrhea.

Potential Synbiotic 365 Side Effects

As genera (the plural of genus), WebMD, Examine.com, and the Natural Medicines Database report that Lactobacillus and Bifidobacteria are likely safe for adults and children when taken as directed. Common side effects, if any, for the genera include mild, temporary intestinal gas or bloating, as well as stomach or intestinal upset.

» Related: Common Probiotic Supplement Side Effects

Outside of this, WebMD indicates Saccharomyces boulardii could rarely “cause fungal infections that can spread through the bloodstream to the entire body (fungemia).” No dosages or other specifics listed.

Whether you’re considering Synbiotic 365 or another probiotic-containing supplement, have an in-depth conversation with a healthcare provider before ordering. In addition to making recommendations that could maximize value, they can also help minimize any potential side effects based on your diagnosis.

How Much Does Synbiotic 365 Cost?

Synbiotic 365 is only available on the United Naturals website, priced as follows:

  • 1 Box: $45
  • 3 Boxes: $119 ($39.67 per box)
  • 6 Boxes: $229 ($38.17 per box)

All orders come with a 30-day refund policy, less S&H, which customers can request by calling support at 844-794-7728.

Synbiotic 365 vs. Competing Probiotic & Prebiotic Supplements

We didn’t encounter anything with the same (or very similar) formulation as Synbiotic 365 during our research.

However, we did come across dozens of competing synbiotic supplements like Syntol AMD ($40, 90 capsules), Dr. Axe Formula SBO Probiotic ($41, 60 capsules), HLC Synbiotic Intensive ($43, 7 sachets), NutriCology SymBiotics with FOS ($23, 40 servings), and Renew Life Women's Daily Probiotics plus Prebiotics ($28, 60 capsules).

From a high-level perspective, these supplements are alike in that they’re priced competitively with one another, and that each combines a relatively similar blend of probiotics, prebiotics, and other vitamins and minerals.

These often include many of the same species among the Lactobacillus and Bifidobacteria genera, vitamins like C and many within the B family, and even secondary ingredients like chicory root and different fruit extracts as energy sources.

Zooming in, the differences between Synbiotic and competing supplements mostly relate to the quantities of each ingredient they contain, as well as the form in which they’re available (e.g., capsules vs. loose powder).

Is either of these criteria important when choosing a synbiotic supplement? Perhaps not. Here’s why:

First, while probiotics and prebiotics are certainly beneficial on their own, Cynthia Sass, RD, Health contributing nutrition editor, emphasizes: “Right now we don’t have a lot of data to show that synbiotics are more effective than, say, taking probiotics [supplements] and eating a diet rich in prebiotics.”

Next, even if they are eventually shown equally as useful, Cynthia emphasizes that "Your overall pattern of eating still has the greatest impact on your health protection or risk,” so “don’t think that taking [one of these supplements] means you don’t have to pay attention to your diet.”

Together, from a value perspective, she recommends that “until more comprehensive research is conducted on synbiotics, consider sticking to swallowing a probiotic supplement or eating probiotic-rich foods in addition to prebiotic foods.”

Our Bottom Line on Synbiotic 365

At $45 per box, Synbiotic 365 seems priced at the upper end of the spectrum compared to some other popular synbiotic supplements but has a middle-of-the-road price compared to probiotic supplements in general—some of which can near the $100 mark.

And as we outline in our Probiotic Supplement Buyer’s Guide, paying more for one of these supplements doesn’t typically translate into improved results, as reported by customers.

Other pointers we mention in the article include making sure the manufacturer provides a complete list of all the bacteria strains, as well as their dosage (as measured in colony-forming units, or CFU), both of which United Naturals lists for Synbiotic 365.

However, the company also adds a handful of vitamins that, according to sites like Examine.com and WebMD, might not provide much value for the money unless you’re deficient. Furthermore, we didn’t encounter any online customer feedback for Synbiotic 365 at the time of our research, and the company wasn’t listed with the Better Business Bureau.

Still, they advertise that all purchases come with a 30-day refund policy if the supplement doesn’t meet your needs, less S&H charges. Just make sure that you talk with your doctor first about overall value based on your diagnosis before ordering, as well as potential side effects or medication interactions.

» Recommended Reading: Best Grains, Fruits, and Vegetables That Improve Digestion


Read 989 Synbiotic 365 Customer Reviews and Complaints

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Average Consumer Rating: 4.7
Rating Snapshot:
5 star: 785 4 star: 151 3 star: 20 2 star: 12 1 star:  21
Bottom Line: 96% would recommend it to a friend
Showing 1-11 of 989
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  • 169 out 171 people found this review helpful

    Great start - poor finish

    • Warner Robins, GA,
    • Dec 31, 2018
    • Verified Reviewer

    My husband and I were loyal users for about 9 months. From the start, this product seemed highly effective. We saw immediate results, including regular bowel movements and decreased bloating. But each time we ordered, they sent us a different "edition" of the product. The first edition was the one that worked. If you looked at the ingredients on the second and third edition, they were entirely different, and those editions did not work for us. All of the bloating and irregular bowel movements returned over the course of the second and third editions. We eventually discontinued. This supplement is way too pricey for it not to work. I'd like to know why the ingredients changed.

    Bottom Line: No, I would not recommend this to a friend

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  • 112 out 119 people found this review helpful

    Best ever!

    • Corinth, NY,
    • Nov 1, 2018
    • Verified Reviewer

    I’m on opiates for back pain and have a very difficult time with my bowel movements, sometimes not going for days! I took a chance and ordered this product. After just a few days I started having bowel movements. They became more and more frequent, and now I’m beginning to go two or three times a day. I also noticed my stomach wasn’t bloated or sick as I would every day feel sick. I also noticed that I get up in the morning wide awake and cannot take any more small naps during the day. This is too hard to believe, but it’s true! All I can say is WOW! And I am very grateful for this product. It definitely is not s rip-off! I’m totally on board with this and suggest you do too.

    Bottom Line: Yes, I would recommend this to a friend

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  • 100 out 111 people found this review helpful

    No product received

    • Romeoville, IL,
    • Dec 15, 2018
    • Verified Reviewer

    I have called three times and tried to talk to a customer rep only to be disconnected after five minutes. I called their helpline and waited ten full minutes never to reach anyone. I traced the shipment to Salt Lake City where it is lost. You cannot even think of getting through to the USPS at this time of year. Therefore I want my order number 224481962 ordered on December 7th canceled immediately.

    Bottom Line: No, I would not recommend this to a friend

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  • 95 out 100 people found this review helpful

    United Natural processed my incomplete order

    • New York,
    • Jan 11, 2019
    • Verified Reviewer

    I was in the process of ordering Synbiotics 365 online. I filled out the payment info and I was pushed to buy more bottles and Enzym 365. I started getting alarmed by the aggressive sales technique, so I went online to check out reviews of the product. I read the reviews here and decided not to buy. I closed out the website without getting to the end to place the order. But I got an email from United Natural that says the order has been processed. I immediately replied, telling them I didn't complete the order. I got no response. I called the phone number in the email and I was told the office is only open Monday - Friday.

    I'm pretty upset with the company right now. I'll report back whether the company cancels it.

    Bottom Line: No, I would not recommend this to a friend

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  • 91 out 97 people found this review helpful

    United Naturals doesn’t return your phone call

    • Albuquerque, NM,
    • Jan 11, 2019
    • Verified Reviewer

    I tried this supplement for 30 days with no positive results. I called three times within the 30-day return window and they never returned my calls. Finally, on the 4th attempt, they answered and told me I was beyond the 30-day return window. For breaking their return guarantee, they belong in the scam group.

    Bottom Line: No, I would not recommend this to a friend

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  • 72 out 78 people found this review helpful

    Nothing special

    • Boise, ID,
    • Jan 23, 2019
    • Verified Reviewer

    I have been taking "365" for about three weeks and nothing significant has happened to change my digestion. Don't waste your money, just go buy good B complex vitamins and a good probiotic from your local drugstore or health food store. Ask your pharmacist or health food expert for a good brand. I foolishly ordered, didn't even try for a refund because of the comments by other people.

    Remember, what you read online is not always true.

    Bottom Line: No, I would not recommend this to a friend

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  • 70 out 73 people found this review helpful

    Tremendous improvement

    • Sarasota, FL,
    • Nov 26, 2018
    • Verified Reviewer

    I have been taking SYN 365 for three months now and see a huge difference in how I feel. I have always been very healthy but want to continue to improve. I have found that I am no longer hungry all the time despite eating less now than I did before taking SYN 365. I find myself satisfied with less and better food choices and having more energy. I walk 3 miles a day or more and sleep soundly. No stomach issues with taking the supplement.

    Bottom Line: Yes, I would recommend this to a friend

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  • 66 out 70 people found this review helpful

    Less than positive results

    • California,
    • Jan 20, 2019
    • Verified Reviewer

    I ordered this probiotic as I was told a probiotic would be helpful for me. I have used it for a week and it has caused stomach cramping and diarrhea. I called to see how to obtain a refund, but the mailbox was full. I have now written them and I hope I get an answer as this is obviously not the product for me and I bought three boxes of it.

    Bottom Line: No, I would not recommend this to a friend

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  • 60 out 64 people found this review helpful

    Scam. Will not refund my money like they said.

    • Washington,
    • Feb 4, 2019
    • Verified Reviewer

    The product made my stomach worse. I have been trying to get my refund back since I returned it December 12th. This is now January 28th. They have given me excuse after excuse not to refund the money. I finally turned them over to my bank for fraud.

    Bottom Line: No, I would not recommend this to a friend

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    • Feb 22, 2019

      Company Response from United Naturals

      Beth, please reach out to support@unitednaturals.com and include your order number and the subject "HIGHYA REVIEW" so I can look into this personally.


  • 58 out 81 people found this review helpful

    Expected more

    • California,
    • Jan 5, 2019
    • Verified Reviewer

    I ordered this product, which I usually don't order online (never know if scam using Dr. Oz, etc.). I never received an email update about the order if it was received or on its way. I finally received the product and there was no "thank you for ordering, welcome, and here is an informational brochure." No, nothing! If I am spending as much as I did, there should have been something in this box. I should not have to go online for information on the product. Just a return label. Is this what you are expecting from all your customers? RETURNS. I will start using on the first day of the year as a resolution to a change in my way of life. I am getting back to making time again to the healthy lifestyle I have had for years and to see my body's downfall. So I will update you all and let you know if I will recommend to others.

    Bottom Line: No, I would not recommend this to a friend

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  • 57 out 60 people found this review helpful

    SCAM!

    • Ontario, Canada,
    • Feb 12, 2019
    • Verified Reviewer

    I purchased on January 10, 2019, and it is now February 4, 2019 and I have yet to receive my order. My credit card has been billed almost $500.00, yet no product. False info on United Naturals website, stating warehouse in Montreal, yet it does not exist.

    Bottom Line: No, I would not recommend this to a friend

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    • Feb 22, 2019

      Company Response from United Naturals

      Nelson, I am sorry you are experiencing a delay with your order. As you know, when we ship from the United States to Canada we cannot control the amount of time that Customs holds the package for review. Sometimes they are released the same day and sometimes they take much longer.

      Our website provides a Canadian address because we have a Corporate office there, not a shipping facility. Nothing on the website indicates that we would be shipping from Canada. I am sorry for any confusion.


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