Calocurb Review: The Hops Extract, the Trials and the Real Cost per Day

Calocurb is a caffeine-free capsule built on 250 mg of Amarasate, a bitter hops flower extract, and it has more published human appetite research behind its one ingredient than most products in this aisle. In company-linked trials, the extract lowered hunger during a 24-hour fast and cut how much healthy-weight men ate at lunch. The catch is the routine: the calorie result came from 500 mg, which is 4 capsules a day, an hour before meals, at about $4.00 a day.

Below: what's on the label, what each trial measured, side effects, the real price per day, how Calocurb scores on our rubric, and what we'd pick instead.

What's in Calocurb, and how you take it

Calocurb's label lists one active: 250 mg of Amarasate (New Zealand hops flower extract) per 2-capsule serving, plus rosemary leaf extract at an undisclosed amount, vegetable oil and a delayed-release plant capsule. We checked the brand's US product page on October 19, 2026. A bottle holds 90 capsules for $89.99.

The directions ramp you up over 5 days:

• Days 1 and 2: 1 capsule an hour before a meal.
• Days 3 and 4: 1 capsule twice a day, an hour before meals.
• Day 5 on: 2 capsules twice a day, an hour before meals, on an empty stomach, up to 4 a day.

The brand says effects can last up to 6 hours, and its FAQ gives the timing as 1 to 2 hours before a meal (the main directions say 1 hour). Either way, this is a pre-meal tool. You plan around it. You can see the label details on our Calocurb GLP-1 Activator product card.

How Amarasate is supposed to work

Amarasate is meant to work through bitter taste receptors in the gut lining, which sit on the same cells that release GLP-1, CCK and PYY, the hormones that signal a meal has arrived. The delayed-release capsule exists to carry the bitter compounds past the tongue and stomach to where those receptors are. Our deep dive on the Amarasate hops extract covers the receptor biology in full.

One thing worth knowing before you read any "GLP-1 activator" label: blood GLP-1 is a hard number to measure. The hormone is broken down within minutes, and a 2014 comparison found commercially available GLP-1 assays disagreed badly with each other (Bak et al., 2014). So we weigh appetite and intake results, dose disclosure and tolerability, not a single hormone reading.

Does Calocurb work? What the trials measured

Calocurb's hops extract reduced hunger and food intake in short, controlled trials, mostly run by the New Zealand institute that developed it. Here is each one at its real size.

• Fasting men, 2019. In a crossover trial, 30 men did three 24-hour water fasts, taking placebo, 100 mg or 250 mg of Amarasate twice during each fast. Both doses lowered hunger by more than 10% over the last 6 hours, and the lunchtime hunger rise seen on placebo didn't show up (Walker et al., 2019).
• Fasting women, 2024. The same design in 30 women at 125 mg and 250 mg found significantly lower appetite and lower food cravings than placebo. Two women on the higher dose reported loose stools and one reported heartburn (Walker et al., 2024).
• The calorie trial, 2022. 19 healthy-weight men took 500 mg of hop extract or placebo before an all-you-can-eat lunch and snack. Intake fell from 5,383 kJ on placebo to about 4,450 kJ on the extract, roughly 17% or about 220 calories less. GLP-1, CCK and PYY rose after the meal, but the men didn't report feeling less hungry, and nausea, bloating and stomach discomfort went up slightly (Walker et al., 2022).
• The independent test, 2023. A University of Adelaide team delivered 100 mg or 250 mg of the extract straight into the small intestine, or 250 mg into the stomach. The 250 mg gut dose nudged pyloric pressure and PYY, but none of the doses changed appetite or how much people ate at a buffet (Bitarafan et al., 2023).

Read together, the picture looks dose-dependent. At 500 mg, men ate less. At 250 mg delivered directly to the gut, intake didn't move. That makes the 2022 trial one useful data point, not the whole case, and it means the full 4-capsule protocol is the one with intake data behind it.

What's missing: no trial on the finished Calocurb capsule for weight, and nothing longer than a single day. The fasting studies measured hunger during a water fast, which is a narrower situation than a normal week of eating.

Calocurb side effects

Calocurb's most common side effects are digestive: loose stools, heartburn, nausea, bloating and stomach discomfort showed up in the trials, mostly mild. The brand says about 5% of users get mild digestive discomfort in the first 24 to 72 hours, which is the reason for the 5-day ramp.

The label says it isn't tested for anyone under 18 or for pregnant or breastfeeding women. If you take medication or manage a health condition, check with your doctor or pharmacist first.

Calocurb price per day

Calocurb costs about $2.00 per 2-capsule serving at $89.99 for 90 capsules, and about $4.00 a day on the full 4-capsule protocol. At that rate a bottle the brand calls a 30-day supply lasts 22 or 23 days. The brand advertises 15% off on subscription and a 30-day money-back guarantee on first orders.

So the honest monthly figure, if you follow the directions to the dose that cut intake in the trial, is closer to $120 than $90.

Calocurb on our five-axis rubric

Calocurb scores 16 out of 25 on the rubric we apply to every product, strong on evidence and disclosure and held back by a single mechanism and a demanding routine. Scored on the published Crave Crushers methodology:

Axis (out of 5)	Calocurb	PhenQ	Ozzi Crave Crusher
Pathway coverage	2	3	5
Ingredients and dose disclosure	4	2	4
Science	4	2	4
Value	3	3	4
Format and timing	3	3	4
Total	16	13	21

Calocurb beats most capsules on the science axis because its one ingredient has human appetite trials at a stated dose. It loses on coverage (it works one lever, gut hormones before meals) and on format, since 4 timed capsules a day is a lot to keep up. Our Calocurb vs PhenQ comparison covers the stimulant side of that matchup, and Evolv GLP-1 vs Calocurb covers the other caffeine-free "GLP-1" capsule.

Who Calocurb suits, and who should skip it

Calocurb suits people whose problem is big portions at planned meals, who want a caffeine-free capsule and who will take it an hour before eating. It fits intermittent fasting well, since that is exactly where the hunger trials were run.

Skip it if your cravings hit after dinner rather than before meals, you have a sensitive stomach, or $4.00 a day is more than you want to spend on one mechanism. For other caffeine-free options, our ranking of stimulant-free appetite suppressants scores the field on the same terms, and the appetite suppressant reviews hold the rest of our single-product deep dives.

The alternative we'd pick

Our pick over Calocurb is the Ozzi Crave Crusher drink, which scores 21 out of 25 on the same rubric. It has six named actives at disclosed doses: 8 g allulose, 500 mg L-lysine butyrate, 500 mg konjac glucomannan, chromium, ursolic acid and African mango. That spreads the work across GLP-1 signaling, blood sugar and fullness instead of one gut-hormone trigger, it's caffeine-free, and it's one serving after dinner instead of a pre-meal schedule. If you'd rather stay with a capsule, Ozzi also makes Crave Crusher Capsules, which score 20 on the rubric.

Ozzi's cons are real. There's no published trial on the finished Ozzi formula, while Calocurb's single ingredient has more direct appetite data. Its doses are moderate by design, some people notice the natural butyrate smell, and its sticker price per serving is higher than Calocurb's single serving until you use the bundle or subscription.

Disclosure: Ozzi sponsors Crave Crushers, and we may earn a commission on purchases made through links on this page. Rankings come from the published rubric on our methodology page, and Ozzi's downsides are listed on the same terms as every other product's.

Our verdict on Calocurb

Calocurb is one of the better-evidenced single-ingredient appetite capsules you can buy: a disclosed dose, a plausible mechanism and real human trials on hunger and intake. Its limits are just as clear. The intake result needs the full 4-capsule day, most of the research comes from the ingredient's developer, the one independent trial found nothing at 250 mg, and it only works before meals. Buy it for portion control at lunch and dinner, not for the 9pm cravings.

For the label checks that apply to every craving product, start with our six checks before you buy a natural GLP-1 supplement.

References

• Walker E, Lo K, Tham S, et al. New Zealand Bitter Hops Extract Reduces Hunger During a 24 h Water Only Fast. Nutrients, 2019. PubMed 31766216
• 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. American Journal of Clinical Nutrition, 2022. PubMed 35102364
• Bitarafan V, Fitzgerald PCE, Poppitt SD, Ingram JR, Feinle-Bisset C. Effects of intraduodenal or intragastric administration of a bitter hop extract (Humulus lupulus L.), on upper gut motility, gut hormone secretion and energy intake in healthy-weight men. Appetite, 2023. PubMed 36781111
• Walker E, Lo K, Gopal P. Gastrointestinal delivery of bitter hop extract reduces appetite and food cravings in healthy adult women undergoing acute fasting. Obesity Pillars, 2024. PubMed 39071168
• Bak MJ, Wewer Albrechtsen NJ, Pedersen J, et al. Specificity and sensitivity of commercially available assays for glucagon-like peptide-1 (GLP-1): implications for GLP-1 measurements in clinical studies. Diabetes, Obesity and Metabolism, 2014. PubMed 25041349
• Calocurb label, directions, price and guarantee: calocurb.com US product page, checked 2026-10-19.