Clinical research using Calocurb® has now demonstrated both mechanistic and real-world weight management and body composition benefits across four human studies.
This ground-breaking 4th human clinical, published in July 2026, links the significant activation of GLP-1, CCK and PYY satiety hormones from previous Calocurb studies, to weight loss (GLP-1, CCK and PYY), fat loss (CCK) and lean muscle maintenance (PYY).
Calocurb has clinically demonstrated improvements in overall body composition which is often lacking with other GLP-1 therapies where a significant amount of weight loss, is often lean muscle mass loss.
First, What Is Calocurb?
Calocurb is the brand name for a supplement built around Amarasate, an extract made from a special variety of bitter hops grown in New Zealand.
Here's the basic idea: certain taste receptors in your gut — the ones that detect bitterness (TAS2Rs) — sit on specialized "enteroendocrine cells" in the lining of the gastrointestinal (GI) tract. These cells produce hormones that tell your brain "you're full" and also slow down stomach emptying. The result? Your body senses you've had enough food, so you stop eating. When Amarasate reaches your intestine, it activates the TAS2Rs, which triggers the enteroendocrine cells to release more of three natural "fullness" hormones:
- GLP-1 (glucagon-like peptide-1) — yes, the same hormone that drugs like semaglutide and tirzepatide mimic synthetically. Calocurb instead prompts your own body to make more of it.
- CCK (cholecystokinin) is linked to fat oxidisation
- PYY (peptide tyrosine tyrosine) is linked to muscle maintenance and preservation
In earlier human studies, Amarasate boosted these hormones well above normal levels — over the levels needed to reduce eating: over 6 x baseline for GLP-1, over 6 x for CCK, and 2 x for PYY.1 That's why the participants ate almost 20% less at their next meal.2 In 24-hour water fasts, Amarasate reduced overall hunger in men by 20%, and in women reduced hunger by 30% and cravings by 40%.34
Until now, though, most of the evidence for Calocurb came from short-term studies or from people simply reporting positive weight results after using it. The question we wanted to answer was: 'does Calocurb help people lose weight over months, under realistic, real-world conditions'? That's exactly what this new study answered.
The Study: What Did They Actually Do?
In 2025, independent researchers in New Zealand ran a 24-week study with 150 adults who were overweight or living with obesity (BMI between 25 and 35 kg/m2).5 Participants were randomly assigned to take either Calocurb or a placebo (a dummy pill), and neither the participants nor the researchers knew who was taking which — this is called a "double-blind" design, and it's considered the gold standard for testing whether something really works.
A few more details, for context:
- Participants were aged 18–45 (mean 35 years) and around ¾ were female
- The mean weight of participants was 189 lb (85.8 kg) and mean BMI was 30 kg/m2
- People were excluded if they were already on weight-loss medication, actively dieting, had recently lost or gained weight, had a GI disease, or had diabetes — so this was testing Calocurb somewhat on its own, not stacked on top of other treatments.
- The Calocurb group started on a low dose and worked up over three weeks to two capsules, taken about an hour before their two main meals, on an empty stomach.
- Everyone — both groups — got basic diet and lifestyle advice every four weeks in a group session, which mimics what happens in the real world rather than an intensive, closely-supervised weight-loss program. Body weight and composition were measured regularly using a specialized body-composition scanner, and blood tests checked that the supplement wasn't causing any issues with liver, kidney, cholesterol, or blood sugar levels
- Only one person per group dropped out specifically due to side effects from the capsules — a reassuring sign that Calocurb was generally well tolerated.
What the Study Found
You can see the results after 24 weeks in the table below. With the exception of the muscle mass change, these differences were all statistically significant, both between the Calocurb and placebo groups, and within the Calocurb group, from the start to the end of the trial. That means these results were not just due to chance. A few things stand out here:
The weight loss was mostly fat, not muscle. This matters a lot. Many weight-loss approaches — including some medications — can cause people to lose muscle along with fat, which isn't great for long-term health or metabolism. In this study, the Calocurb group actually gained almost a kilogram of muscle while losing significant fat (in fact, over six times more fat loss than the placebo group). That's why the change in body weight was actually less than the change in fat mass.
Even though this was not a statistically significant difference from the slight placebo group gain, it does show that Calocurb helped maintain muscle rather than lose it. When researchers adjusted the numbers to account for that muscle gain, the "true" weight loss came out to 5.3%, compared with just 0.7% in the placebo group (which was highly statistically significant).
Here's how the two groups compared after 24 weeks:
| What was measured | Calocurb group | Placebo group |
|---|---|---|
| Body weight change | -8.4 lb / -3.8 kg | -0.9 lb / -0.4 kg |
| Fat mass change | -9.9 lb / -4.5 kg | -1.5 lb / -0.7 kg |
| Visceral (deep belly) fat change (area) | -5.0 in² / -32.5 cm² | -1.4 in² / -9.1 cm² |
| Muscle mass change | +2.0 lb / +0.9 kg | +0.4 lb / +0.2 kg |
Visceral fat dropped the most, proportionally. Visceral fat is the fat that wraps around your internal organs and belly, and it's more closely linked to health risks like heart disease and type 2 diabetes than the fat just under your skin. The Calocurb group lost more than three times as much of it as the placebo group (a statistically significant difference).
The placebo group's pattern is telling. Interestingly, people in the placebo group actually lost some weight in the first 12 weeks — probably just from knowing they were in a study and getting basic lifestyle advice — but then slowly regained it, ending up almost back where they started (Figure 1). This is a very realistic pattern, and it's part of why the Calocurb group's steady, sustained loss over six months is meaningful: it suggests an actual physiological effect, not just a temporary motivation boost.
Figure 1: Change in weight (%) Amarasate (Calocurb) and placebo, adjusted for muscle mass, during 24-week weight loss study.6
Where could Calocurb fit into your journey?
Calocurb isn't going to get you the same dramatic results as the newest injectable or oral medications. It's a natural non-prescription capsule that has clinically shown its possible to achieve statistically significant weight loss, mainly fat loss, while maintaining your muscle. It's about better body composition for the future, not the now.
Where it may fit in to your journey:
As a standalone option for people who want meaningful, sustainable weight loss without a prescription or injections
As support when coming off a GLP-1 medication, to help hold onto the results
As a lower intensity complement alongside a lower dose of an injectable, for people managing side effects or cost
Unlike prescription GLP-1 drugs, Calocurb works by activating your body to release more of its own natural hormones, rather than introducing a synthetic, long-acting version. That's part of why the effect is more moderate — but also likely part of why the side-effect profile tends to be much milder.
The Bottom Line
This new 24-week, placebo-controlled, double-blind trial is the first real proof that Calocurb delivers meaningful, sustained weight loss — averaging 5.3% of body weight when you account for the gain in muscle — while specifically targeting fat (especially the more dangerous visceral kind) while maintaining lean muscle.
As always, talk to your doctor before starting any new supplement, especially if you have an existing health condition or take other medications.
This article is for general educational purposes and isn't a substitute for medical advice. Talk to your doctor before starting any new supplement or weight-management program, especially if you have an existing health condition.
