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Weight Loss Supplements: Comparing Calocurb, Berberine, and Akkermansia

Weight Loss Supplements: Comparing Calocurb, Berberine, and Akkermansia

Injectable weight loss medications like Ozempic and Zepbound have been making headlines over the last few years, thanks to the results they deliver, their massive adoption, and the focus on celebrity use of these drugs. Nikki Glaser even mentioned Ozempic as she opened the Golden Globes ceremony last week (“Good evening, and welcome to the 82nd Golden Globes—Ozempic’s biggest night”) and Zepbound was a sponsor of the show. In fact, about one in eight Americans are using these drugs, and that number goes up to one in five for people whose doctors have told them they need to lose weight.1 These medications work by mimicking a hormone in our body called GLP-1, which makes us feel full and slows down our digestion. Doctors call these medications "GLP-1 receptor agonists" or "GLP-1 RAs" because they activate GLP-1 receptors in our bodies, though they’re typically referred to just as GLP-1s by most people.

Before these new injectable treatments, other prescription drugs included orlistat (Xenical), which blocks fat absorption but could cause embarrassing "oily accidents," and the appetite suppressant combination phentermine-fenfluramine, which had to be withdrawn because it caused heart valve problems.

Alongside these prescription medications, people have been using supplements for weight loss for decades, and some natural remedies go back hundreds of years. For example, guggul has long been used in traditional Indian (Ayurvedic) medicine for weight loss, and King Charles II's mistresses reportedly used heath pea to stay slim.2,3 In fact, this historical use of bitter plants led to the development of Calocurb.

How Calocurb Works

Calocurb contains Amarasate®, a bitter extract from New Zealand hops flowers. Calocurb capsules are specially designed to release their contents in the small intestine, where they activate taste receptors that trigger the body to produce more GLP-1 naturally. (Yes, we have taste receptors all the way down the gut, from the mouth to the anus!). Calocurb increases your body's own GLP-1 production without flooding the body with prolonged and very high levels of artificial GLP-1, as the injectable medications do.

In studies, Calocurb increased GLP-1 production by six times when taken an hour before meals, which led to people eating about 20% less food.4 Research shows you need at least a four-fold increase in GLP-1 to noticeably reduce food intake, which explains why Calocurb works so well.4 It also helped reduce hunger during 24-hour fasting by 25% in men and 30% in women.5,6 Side effects are uncommon, though about 5% of people might experience diarrhea when first starting it.

Other Types of Weight Loss Supplements

There are many different approaches to weight loss supplements. Some contain caffeine-rich ingredients like guarana to boost metabolism, while others use bulking agents like guar gum to make you feel fuller. There are also plant extracts that claim to block fat or sugar absorption.7 For a great summary of weight loss supplements, visit this NIH site. But two supplements that are increasingly being marketed for weight loss are missing from the NIH list, berberine and Akkermansia. So what are these supplements, do they work and how do they compare with Calocurb?

Berberine: The Yellow Wonder

Berberine is a yellow compound found in several plants like goldenseal, Oregon grape, tree turmeric, and barberry. It works by activating an enzyme called AMPK (known as the "metabolic master switch"), which monitors cellular energy levels and controls how our bodies handle sugar and fat. Beyond weight loss, it shows promise for managing blood sugar, cholesterol, blood pressure, and even conditions like polycystic ovary syndrome and certain fungal infections.

However, the weight loss results in humans haven't been as impressive as early animal studies suggested. Scientists have done four major reviews of berberine studies since 2020, looking at anywhere from 10 to 24 different research studies. The results were mixed—some reviews found no significant weight loss, while others showed modest results. Even in the most positive studies, people lost less than 5 pounds (2.2 kg) on average.8-11 One analysis suggested you'd need to take berberine for 50 weeks (!) to get the best results for reducing waist size.10 Side effects can include nausea, stomach pain, bloating, constipation or diarrhea.

Akkermansia: The Gut-Friendly Option

Akkermansia muciniphila is a beneficial bacteria that lives in our gut. It's gained attention because people who naturally have more of this bacteria tend to be leaner.12 It seems to work in several ways: it may help strengthen our intestinal lining, raise body temperature to burn more calories (called thermogenesis), and produce substances that trigger GLP-1 production.13

While studies in overweight mice showed promising results, human research is still limited. In one study of 32 overweight or obese adults, three months of taking pasteurized Akkermansia led to small reductions in weight (5 lbs / 2.3 kg), fat mass (3 lbs / 1.4 kg), waist size (0.6 in / 1.6 cm), and hip size (1 in / 2.6 cm).14 However, none of these changes were statistically significant compared to the placebo group. Interestingly, while the supplement reduced the enzyme that breaks down GLP-1, it didn't actually change blood GLP-1 levels.14

There are some important cautions with Akkermansia. Since it breaks down mucin (a component of intestinal mucus), it might be harmful for people with irritable bowel syndrome (IBS) and polycystic ovary syndrome or endometriosis (both of which make women more susceptible to IBS).12 Also, while having lots of natural Akkermansia in your gut is associated with lower obesity risk,15 it's also found in higher amounts in people with Parkinson's disease or multiple sclerosis.12 Anyone with these conditions should consult their doctor before trying Akkermansia supplements.

The Bottom Line

Of these three supplements, Calocurb has the strongest evidence for increasing GLP-1 levels enough to actually reduce food intake. Doctors specializing in weight management have reported success using it with their patients and over 5 years’ use of Calocurb in New Zealand and the USA has led to many successful weight loss stories. While berberine and Akkermansia show some promise, their weight loss effects in humans have been modest at best. A larger, six-month study of Calocurb use in overweight and obese people is currently underway, which should give us more information about its long-term effectiveness.

Remember, no supplement is a magic solution for weight loss. They work best as part of a healthy diet and exercise program, and it's always wise to talk to your healthcare provider before starting any new supplement.

Table 1: Calocurb vs. Berberine vs. Akkermansia

Supplement Calocurb Berberine Akkermansia
What Is It? Amarasate (bitter hops extract) Plant extract Bacterium
Source Hops flowers Various plants: goldenseal, Oregon grape, tree turmeric, barberry Akkermansia muciniphila, a beneficial bacterium in the gut
Mechanism of Action Activates bitter taste receptors in the gut to naturally increase GLP-1, the ‘stop eating’ hormone Activates AMPK enzyme that monitors cellular energy levels and regulates sugar and fat metabolism Secretes molecules that increase GLP-1 production
Increases body temperature
Primary Benefits
  • Appetite suppression
  • Reduces food cravings / “food noise”
  • Supports weight management by reducing food intake without stimulants or bulking agents
  • Blood glucose regulation
  • Lipid lowering
  • Mixed results in human studies for weight management
  • Reduces body weight and fat mass in obese mice
  • Slight reduction in weight, fat mass, and hip circumference in overweight and obese humans
  • Improves gut barrier function and immunity
Onset of Action
  • One hour to reduce appetite
  • Weight loss depends on degree of appetite suppression
 12 weeks to get an effect
  • Weeks (3-month trial in humans)
  • Weight loss depends on degree of appetite suppression
Side Effects / Cautions Initial diarrhea in 5% of users
  • Bloating
  • Upset stomach
  • Should be used with caution in those with inflammatory bowel diseases
  • Concern about association with Parkinson's or MS
Key Differences
  • Influences appetite regulation by stimulating satiety hormone release and activating the "bitter brake"
  • Primarily used as a natural appetite suppressant and weight management aid
  • Targets metabolic pathways, primarily through AMPK activation, affecting glucose and lipid metabolism
  • Often used for blood glucose regulation, improving insulin sensitivity, and lipid management
  • Increases GLP-1 in mice but in the only human study, did not change GLP-1 and had only a mild effect on weight loss
  • Marketed as an aid to increase GLP-1

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References

  1. Montero A, Sparks G, Presiado M, Hamel L. KFF Health Tracking Poll May 2024: The Public’s Use and Views of GLP-1 Drugs. KFF. Published May 10, 2024. Accessed January 11, 2025. https://www.kff.org/report-section/kff-health-tracking-poll-may-2024-the-publics-use-and-views-of-glp-1-drugs-findings/
  2. Sarup P, Bala S, Kamboj S. Pharmacology and phytochemistry of oleo-gum resin of Commiphora wightii (Guggulu). Scientifica (Cairo). 2015;2015:138039. doi:10.1155/2015/138039
  3. Mair G, Henry S. How the herb Charles II used to keep royal mistresses in shape could help fight today’s obesity epidemic. Mail Online. Published March 19, 2008. Accessed September 23, 2024. https://www.dailymail.co.uk/health/article-527413/How-herb-Charles-II-used-royal-mistresses-shape-help-fight-todays-obesity-epidemic.html
  4. Walker EG, Lo KR, Pahl MC, et al. An extract of hops (Humulus lupulus L.) modulates gut peptide hormone secretion and reduces energy intake in healthy-weight men: a randomized, crossover clinical trial. Am J Clin Nutr. 2022;115(3):925-940. doi:10.1093/ajcn/nqab418
  5. Walker E, Lo K, Tham S, et al. New Zealand bitter hops extract reduces hunger during a 24 h water-only fast. Nutrients. 2019;11(11):2754. doi:10.3390/nu11112754
  6. Walker E, Lo K, Gopal P. Gastrointestinal delivery of bitter hop extract reduces appetite and food cravings in healthy adult women undergoing acute fasting. Obes Pillars. 2024;11:100117. Published 2024 Jun 20. doi:10.1016/j.obpill.2024.100117
  7. Office of Dietary Supplements - Dietary Supplements for Weight Loss. NIH.gov. Updated March 22, 2021. Accessed January 11, 2025. https://ods.od.nih.gov/factsheets/WeightLoss-Consumer/
  8. Amini MR, Sheikhhossein F, Naghshi S, et al. Effects of berberine and barberry on anthropometric measures: A systematic review and meta-analysis of randomized controlled trials. Complement Ther Med. 2020;49:102337. doi:10.1016/j.ctim.2020.102337
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  10. Zamani M, Zarei M, Nikbaf-Shandiz M, Hosseini S, Shiraseb F, Asbaghi O. The effects of berberine supplementation on cardiovascular risk factors in adults: A systematic review and dose-response meta-analysis. Front Nutr. 2022;9:1013055. Published 2022 Oct 14. doi:10.3389/fnut.2022.1013055
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  12. Chiantera V, Laganà AS, Basciani S, Nordio M, Bizzarri M. A Critical Perspective on the Supplementation of Akkermansia muciniphila: Benefits and Harms. Life (Basel). 2023;13(6):1247. Published 2023 May 24. doi:10.3390/life13061247
  13. Cani PD, Knauf C. A newly identified protein from Akkermansia muciniphila stimulates GLP-1 secretion. Cell Metab. 2021;33(6):1073-1075. doi:10.1016/j.cmet.2021.05.004
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