ColonBroom GLP-1 Booster review

Our take: a berberine product without a berberine dose

ColonBroom made its name with a flavoured psyllium drink. Its GLP-1 Booster is something else entirely: a capsule built around berberine, the plant alkaloid that social media calls "nature’s Ozempic". There is no fibre in it, and it has nothing to do with the brand’s original product beyond the name.

Berberine is a reasonable ingredient to build on. Of everything sold as a natural GLP-1 product, it has one of the larger bodies of human weight research. The problem is how little of it this label can promise. The panel lists 200 mg of Berberis aristata bark powder — the weight of the ground bark, not of the berberine inside it — and the weight research NCCIH summarises used more than 1,000 mg of berberine a day. The other three ingredients have no weight effect in their own research at any dose.

Around that sits a product that has changed formula twice since April 2025, gives four different sets of directions, and on Amazon promises "zero side effects" while ColonBroom’s own safety article lists them. Our view: if you want to try berberine, buy a product that states how much berberine you are getting. This one does not.

This is a desk review of the labels, listings and published research. Nobody at SharpAndLean has taken the product.

Which ColonBroom GLP-1 are you buying?

At least three different products have been sold under this name. The one in your basket depends on where you buy it and when.

The berberine source is the same 200 mg in both current versions; the store’s one-a-day capsule trims the other two plant extracts from 200 mg to 125 mg. Reviews, ratings and testimonials attached to any one version tell you little about the others, and the original listing — with 1,364 ratings — sells a formula that shares only its berberine with what the brand now makes.

What is on the label

The Supplement Facts panel on the Amazon listing linked here gives a serving of two vegetarian capsules and 30 servings a bottle:

• Berberis aristata bark powder, 200 mg — "naturally occurring berberine", with no berberine percentage.
• Polygonum cuspidatum root extract 200:1, 200 mg — Japanese knotweed, "standardized to contain resveratrol", with no resveratrol percentage.
• Quercetin dihydrate, 200 mg — from Sophora japonica flower.
• Zinc (as zinc oxide), "15mcg", 136% of the daily value.

Credit where it is due: every ingredient has an amount, and there is no proprietary blend. But two of the four amounts are the weight of a plant material rather than of the compound the product is sold on, and "200:1" describes how concentrated an extract is, not how much resveratrol it contains.

The zinc line cannot be right as printed. The daily value for zinc is 11 mg, so 136 per cent of it is 15 mg — a thousand times more than 15 mcg. ColonBroom’s own store gives 15 mg, so the unit on the Amazon panel is almost certainly a typo. It is a small error, and exactly the kind our guide to reading a supplement label tells you to check: the panel is the one part of the packaging that has to be accurate, and this one is not.

Four sets of directions

How much to take depends on which ColonBroom page you read:

• The store page: "Take 1 pill 30 minutes before eating."
• ColonBroom’s own safety article: "Take 2 capsules about 30 minutes before your largest meal."
• The Amazon panel: a serving of two capsules. The Amazon infographic: "One capsule with water before a meal."
• The Amazon directions text: with meals, at breakfast or lunch, with a full glass of water.

Some of this is the reformulation — the one-a-day capsule really is one a day. But a buyer of the 60-capsule bottle is told both one and two, and the difference halves or doubles an already small berberine intake. Follow the panel on the bottle you actually receive.

The GLP-1 claim

ColonBroom describes the product as "a natural GLP-1 supplement designed to support appetite control", and the Amazon label says "clinically tested actives". There is no trial of the product. "Clinically tested actives" means the ingredients have been studied somewhere, at some dose, for something.

The two GLP-1 papers ColonBroom’s own article cites are worth knowing about. One is a 2024 narrative review of the pathways by which berberine may raise GLP-1, written from the perspective of type 2 diabetes treatment. The other is a 2025 study showing quercetin increased GLP-1 release from a human intestinal cell line in a dish. Neither measured GLP-1, appetite or weight in people taking these ingredients, let alone this capsule. Our GLP-1 explainer covers why raising the hormone slightly is not the same as what the drugs do.

One source of confusion to clear up: ClinicalTrials.gov lists a completed 69-person trial of a "GLP-1 Booster". It is a different product from a different sponsor — green tea, gardenia, turmeric, fenugreek, ginseng and white kidney bean extracts — with no connection to ColonBroom.

Berberine: the dose problem

NCCIH, the US government’s centre for complementary health research, summarises a 2022 meta-analysis of berberine for weight: 18 studies on body weight and 23 on BMI found significant decreases in both. It also calls the evidence inconclusive, notes that many of the studies had a high risk of bias, and says the effects were seen primarily at more than 1 gram a day for more than 8 weeks.

This label gives 200 mg of bark powder a serving. Berberine is one of several alkaloids in Berberis bark, and the label does not say what share of the powder it makes up. Even if every milligram were berberine, one serving would be a fifth of the lowest amount associated with a weight effect. On the store’s one-capsule directions, it would be a fifth of a serving that was already a fifth.

Much of the berberine research was done in people with type 2 diabetes, and a lot of it used purified berberine hydrochloride. ColonBroom’s May 2026 article on the product names "Berberine Hydrochloride" as the ingredient and its safety article says "Berberine: 200 mg"; the panel on the Amazon bottle says bark powder. Those are not the same thing, and only the panel is a legal statement of what is in the capsule.

Resveratrol and quercetin

The two supporting ingredients have been studied for weight, and the results are not encouraging. A 2026 meta-analysis of 23 randomised trials of resveratrol in 1,005 people with overweight or obesity found no significant effect on body weight, BMI or fat mass, and a small reduction in waist circumference of about 2 cm. For quercetin, a 2023 umbrella review of meta-analyses found no effect on body measurements, blood lipids, fasting glucose or inflammation, and a small drop in systolic blood pressure.

So the question of whether 125 to 200 mg is enough barely arises: neither ingredient moves weight in its own research. Zinc at 15 mg is an ordinary daily amount of an essential mineral, within the 40 mg adult upper limit. It is not a weight-loss ingredient.

What the listing promises

The claims have softened as the formula changed. The 60-capsule Amazon bottle says "promotes weight loss" and "enhances mood and reduces emotional eating"; the store’s 30-capsule bottle says "supports weight management" and "supports mood balance and healthy dietary choices". The softer wording is closer to what the ingredients can support.

The Amazon images have not caught up. One is headed "Drop your first pound in 3 weeks!" over a before-and-after pair of torsos, and says to expect fewer cravings and more energy within one to two weeks. Another is headed "Zero Side Effects!", with "NO nausea" and "NO constipation". ColonBroom’s own safety article says berberine may cause mild nausea, stomach discomfort, gas or changes in bowel habits, and NCCIH lists nausea, abdominal pain, bloating, constipation and diarrhoea among the side effects reported in berberine research.

On ratings, both Amazon listings stood at 3.4 out of 5 on 27 September 2026: 173 ratings on the new-formula listing, 23 per cent of them one star, and 1,364 on the original, 27 per cent one star. ColonBroom’s store page shows "12,300 reviews" without saying where they come from. A star rating mixes delivery, price and expectation, and says little about effect.

Price, subscription and refunds

On 27 September 2026 ColonBroom’s store opened on its subscription tab, where a single bottle shows as $49.99 with monthly delivery. Bought once, the same bottle is $69.99. Both are shown against a crossed-out $85.99.

Two terms matter before you choose a subscription. ColonBroom’s help centre says that if you cancel before the first recurring charge, you pay the difference between the subscription price and the one-time price — the discount is effectively clawed back. After the first renewal you can cancel without that charge.

And refunds are narrower than "try it and see". The refund policy covers goods that are faulty or not as described, reported within 14 days of delivery with visual proof, returned unopened in the original packaging. On subscriptions, only the initial purchase is eligible, and US and Canadian customers have $15 deducted for the return label. An opened bottle that simply did not work for you is not covered.

Side effects and who should avoid it

At these amounts the gastrointestinal effects reported at gram doses of berberine are less likely, but not ruled out. The more important cautions are about who should not take berberine at all. NCCIH says berberine exposure has been linked to a harmful build-up of bilirubin in infants, that it is likely unsafe for infants, and that it may be unsafe in pregnancy or while breastfeeding. It is known to interact with cyclosporine, the transplant drug, and NCCIH advises checking with a clinician before taking it alongside any medicine.

ColonBroom’s own safety article adds that people on blood sugar or blood pressure medicines should check first, that children should not use it, that people with heart rhythm problems should avoid it, and that it should be stopped two weeks before surgery. Those warnings are sensible. They are also missing from the Amazon images that promise zero side effects.

Sources and shopping: what to check

• Match the formula. Check the panel on the listing against the table above before you order, and again when the bottle arrives.
• If berberine is what you want, look for a label that states the berberine content in milligrams, not the weight of a bark or root powder.
• Decide on one capsule or two from the panel on your bottle, not from an infographic.
• Before subscribing, read the cancellation clause: cancelling before the first renewal costs you the discount back.
• If you take any regular medicine, are pregnant or breastfeeding, or have surgery coming up, ask a clinician before starting.

Our commercial link points to the new-formula Amazon listing; it earns a commission at no extra cost to you and has not changed the score. If a GLP-1 product is what you are after, our ranking of GLP-1 supplements puts every one we have reviewed side by side, and our guide to natural GLP-1 alternatives covers the foods and habits with better evidence than any capsule. ColonBroom’s original product is reviewed separately in our ColonBroom psyllium review.