Thorne Berberine (1,000 mg)
by Thorne · capsule ·
Well-evidenced berberine for metabolic support — but the effective dose is rough on a lot of stomachs.
- Format
- capsule Pill
- Best price
- $1.47 per serving
- Pathways
- 3 hunger dimensions
- Headline dose
- 450 mg Berberine HCl
- Caffeine
- Caffeine-free evening-friendly
- Bloat risk
- Medium Berberine GI at 1,000 mg
3/7 hunger pathways
- Blood-sugar stability Berberine HCl, Berberine Phytosome
- Insulin sensitivity
- GLP-1 / gut-hormone
The short version
Thorne Berberine is a well-made, fully dosed bottle of a slow, specific ingredient: 1,000 mg of berberine compounds per 2-capsule serving, third-party contents certified, at about $1.47 a day. It's worth buying if you want berberine for glucose or cholesterol support, you'll take it with meals for months, and you've cleared it with your doctor. It isn't an appetite product, and most disappointed buyers bought it for the wrong job.
How it scores
Every score is derived from publicly verifiable facts. See the full methodology and Value Index formula.
Ingredients & doses
| Ingredient | Dose | Pathway | Notes |
|---|---|---|---|
| Berberine HCl (from Berberis aristata) | 450 mg | Blood-sugar stability | Per 2-capsule serving. |
| Berberine Phytosome Berberine Phytosome | 550 mg | Blood-sugar stability | Phospholipid complex intended to improve absorption; total berberine compounds = 1,000 mg/serving. |
How it claims to work
Berberine is a plant alkaloid the brand says supports healthy glucose and lipid metabolism, partly via the AMPK energy-sensing pathway, with the phytosome form intended to improve absorption.
The evidence
Berberine has multiple human RCTs and meta-analyses for fasting glucose, HbA1c, and lipids; absorption is naturally poor (the rationale for the phytosome). The casual "nature’s Ozempic" label is not supported by head-to-head GLP-1 drug trials.
Strengths
- Berberine has real human RCT evidence for glucose and lipid markers.
- Full dose (1,000 mg) disclosed, with an absorption-enhanced phytosome form.
- Reputable, third-party-tested brand.
Watch-outs
- Berberine commonly causes GI distress — cramping, diarrhea, constipation — and at the 1,000 mg+ effective dose it is hard for many people to tolerate.
- A glucose/metabolic supplement, not a craving formula; appetite effects are indirect.
- Capsules only.
Price & value
Taste & format: Capsules (2 per serving) with food, often split morning and evening.
Thorne Berberine (1,000 mg): the full review
What Thorne Berberine is, and who it's for
Berberine is a bright yellow plant alkaloid pulled from barberry, goldenseal and a few related plants. Its headline action is switching on AMPK, an energy-sensing enzyme, and the brand says it supports healthy glucose and lipid metabolism through that route.
Thorne's version pairs plain berberine HCl with a phytosome, a phospholipid complex intended to work around berberine's poor absorption. Retail listings describe it as NSF Contents Certified, meaning an outside lab checks that what's on the label is in the capsule.
It fits someone whose goal is glucose or cholesterol markers over months and who values testing over the lowest price. It doesn't fit someone whose problem is evening cravings, because berberine's lane is glucose and insulin, not hunger. The rest of the shelf is in our berberine and metabolic category.
What the label says
A serving is 2 capsules. The label lists 450 mg of berberine HCl from Indian barberry (Berberis aristata) plus 550 mg of Berberine Phytosome, and totals that as 1,000 mg of berberine per serving. A bottle holds 60 capsules, 30 servings.
| Item | Thorne label | What the research used |
|---|---|---|
| Berberine HCl | 450 mg | Plain berberine, roughly 1 to 1.5 g a day, split across 2 or 3 meals |
| Berberine Phytosome | 550 mg (weight of the complex) | No outcome trial on the phytosome form |
| Daily total | 1,000 mg | About 1 g a day for lipids and weight; about 1.8 g for insulin markers |
One thing the label doesn't tell you. A phytosome is berberine bound to phospholipid, so that 550 mg is the weight of the complex, not of berberine alone. How much berberine sits inside it isn't printed, so we read the 1,000 mg as Thorne's total rather than a pure-berberine figure.
Two naming traps. This product used to be sold as Berberine-500, and Thorne also sells a separate 200 mg berberine HCl capsule, so if a listing looks cheap, check which one it is. For the ingredient on its own, see our berberine deep dive.
What the evidence shows
Every trial below is on berberine, not on this bottle. Nearly all of them enrolled adults with diagnosed type 2 diabetes, often on medication, so what they measured was a supplement added to treatment in people whose numbers started high.
Glucose. Xie and colleagues pooled 37 randomized trials covering 3,048 people with type 2 diabetes and found fasting glucose fell 0.82 mmol/L and HbA1c fell 0.63 points against control (Frontiers in Pharmacology 2022). A subgroup finding in the same paper: the effect tracked how high people's numbers started, so the closer you already are to normal, the less there is to move.
Lipids. Across 18 placebo-controlled trials in 1,788 people, berberine lowered LDL cholesterol by 0.46 mmol/L and triglycerides by 0.34 mmol/L (Blais and colleagues, Drugs 2023). Small and consistent.
Dose and time. A dose-response meta-analysis landed on roughly 1 g a day as the efficient dose for triglycerides, cholesterol and weight, with about 1.8 g a day looking more efficient for insulin markers, and put the most efficient window for fasting glucose at about 40 weeks from the start (Zamani and colleagues, Frontiers in Nutrition 2022). Thorne's serving sits right on the 1 g mark. The 40 weeks is the part nobody puts on the label.
Weight. Real and small. A 2026 review pooled 23 trials and found body weight down 0.88 kg and waist down 1.32 cm (Elahi Vahed and colleagues, International Journal of Obesity). None of these trials measured hunger, snacking or fullness as an outcome.
The phytosome. Thorne's absorption angle rests on one human pharmacokinetic study. Petrangolini and colleagues gave healthy volunteers plain berberine or Berberine Phytosome and found the phytosome raised bioavailability around 10 times on a molar basis (Evidence-Based Complementary and Alternative Medicine 2021). Every author worked at Indena, the company that makes the ingredient, and higher blood levels are a reason to expect a better result rather than a measured one. We haven't found a trial that ran the phytosome against plain berberine on glucose or lipids. The trials that built berberine's reputation used the plain, poorly absorbed form.
Side effects, tolerability, and who should skip it
The stomach complaints are real and less dramatic than some reviews make them sound. In the Blais analysis, gastrointestinal side effects were reported in 2% to 23% of people taking berberine versus 2% to 15% on placebo, with no serious adverse events across the 16 trials that reported them. Cramping, loose stools and constipation are common enough at 1,000 mg and up that plenty of people never reach a dose that matches the studies.
The drug interaction list is the section we'd want a friend to read. In a randomized crossover trial, healthy men took 300 mg of berberine 3 times a day for 2 weeks. Afterwards, CYP2D6 activity dropped sharply, CYP2C9 activity fell, and exposure to the CYP3A4 test drug midazolam rose 40% while its clearance fell 27% (Guo and colleagues, European Journal of Clinical Pharmacology 2012). A systematic review classed berberine as a weak, not moderate or potent, inhibitor of CYP3A4 and CYP2D6 at common doses (Hermann and von Richter, Planta Medica 2012). Weak still matters for drugs with a narrow safety margin, and stacking berberine on prescription glucose-lowering drugs raises a real risk of low blood sugar.
Skip it if you take daily medication and haven't cleared it with a doctor or pharmacist, if you're pregnant, nursing or trying to conceive (Thorne's label warns against all three), if your stomach is already touchy, or if you want to feel something within a week or two.
Price and value
A bottle is $44 at list for 30 servings, about $1.47 a day. Thorne offers a subscription at the same $44. We found no money-back guarantee listed.
The comparison that matters is NOW Berberine Glucose Support, which delivers 1,200 mg a day for about $1.00 on a 3-softgel schedule. Thorne is roughly $0.47 a day more for fewer listed milligrams, on a bet that the phytosome's better absorption converts into better results, which nobody has measured.
Thorne scores 17 out of 25 on our rubric: 4 of 5 on ingredients (full dose disclosed, minus a point because the phytosome's berberine content isn't broken out), 4 on science, 4 on value, 3 on pathway coverage and 2 on format and timing. The scoring logic is on our methodology page. The third-party testing is the part of the price we'd defend first.
How to take it, and what to expect
Take the 2 capsules with food, split across 2 meals, the fix the trials used for the stomach side effects and berberine's short half-life.
Give it months, not days. The efficient window for fasting glucose in the dose-response analysis ran to about 40 weeks.
On cravings, expect an indirect effect at best. Steadier post-meal glucose can take some edge off a sugar crash, but the casual nickname that sells so much berberine isn't backed by any head-to-head trial against the prescription drugs. If evening cravings are the problem, this is the wrong category. It's caffeine-free, so the evening dose won't affect sleep.
How Thorne Berberine compares
Against NOW Berberine, our scoring puts them level, because they're the same ingredient wearing different jackets. NOW gives you more milligrams for less money on a 3-a-day schedule that mirrors how the trials dosed. Thorne gives you the absorption study and the testing. The full head-to-head is in Thorne vs NOW Berberine.
Against a viscous fiber like Metamucil psyllium, you're choosing a gentler route to steadier post-meal glucose with no interaction list, at a fraction of the price, and with a dose gap of its own. We rank the whole shelf in our blood sugar supplement rankings, where berberine takes first on evidence volume and Thorne is the pick if the absorption engineering is worth $0.47 a day to you.
Our longer write-up, with the scoring axis by axis, is the Thorne Berberine review.
Frequently asked questions
Does Thorne Berberine work?
For glucose and lipid markers, berberine has a real record: 37 pooled trials found fasting glucose down 0.82 mmol/L and HbA1c down 0.63 points in people with type 2 diabetes, with the effect tracking how high numbers started. There's no trial on this specific bottle, and nothing in the research measured appetite.
What are the side effects of Thorne Berberine?
Mostly digestive: cramping, loose stools or constipation, reported in 2% to 23% of people on berberine versus 2% to 15% on placebo across trials. Splitting the 2 capsules across 2 meals is the usual fix. Berberine also slows the enzymes that clear many prescription drugs, so check with a doctor or pharmacist first.
How long does berberine take to work?
Longer than most people expect. A dose-response meta-analysis put the most efficient window for fasting glucose at about 40 weeks from the start, and the lipid and weight effects came from months-long trials. Nothing in the evidence supports expecting a change in days.
Does Thorne Berberine have caffeine?
No. It contains 0 mg of caffeine. The label lists berberine HCl and Berberine Phytosome, nothing else active, so the evening dose won't affect sleep.
How much does Thorne Berberine cost?
$44 for 60 capsules, 30 servings, about $1.47 a day. The subscription is also $44. NOW Berberine delivers 1,200 mg a day for about $1.00, roughly $0.47 a day less.
Can I take Thorne Berberine with my medication?
Ask your doctor or pharmacist first. In a crossover trial, 2 weeks of berberine at 300 mg 3 times daily slowed CYP2D6, CYP2C9 and CYP3A4 activity and raised exposure to a CYP3A4 test drug by 40%. That matters most for drugs with a narrow safety margin and for anything that lowers glucose.
References
- Xie W, Su F, Wang G, et al. Glucose-lowering effect of berberine on type 2 diabetes: A systematic review and meta-analysis. Front Pharmacol. 2022;13:1015045. PMID 36467075
- Blais JE, Huang X, Zhao JV. Overall and Sex-Specific Effect of Berberine for the Treatment of Dyslipidemia in Adults: A Systematic Review and Meta-Analysis of Randomized Placebo-Controlled Trials. Drugs. 2023;83(5):403-427. PMID 36941490
- Zamani M, Zarei M, Nikbaf-Shandiz M, et al. The effects of berberine supplementation on cardiovascular risk factors in adults: A systematic review and dose-response meta-analysis. Front Nutr. 2022;9:1013055. PMID 36313096
- Elahi Vahed I, Shahir-Roudi E, Nojumi S, et al. The effect of berberine on obesity indices: a systematic review and meta-analysis. Int J Obes (Lond). 2026;50(1):53-73. PMID 41310257
- Petrangolini G, Corti F, Ronchi M, et al. Development of an Innovative Berberine Food-Grade Formulation with an Ameliorated Absorption: In Vitro Evidence Confirmed by Healthy Human Volunteers Pharmacokinetic Study. Evid Based Complement Alternat Med. 2021;2021:7563889. PMID 34904017
- Guo Y, Chen Y, Tan ZR, Klaassen CD, Zhou HH. Repeated administration of berberine inhibits cytochromes P450 in humans. Eur J Clin Pharmacol. 2012;68(2):213-7. PMID 21870106
- Hermann R, von Richter O. Clinical evidence of herbal drugs as perpetrators of pharmacokinetic drug interactions. Planta Med. 2012;78(13):1458-77. PMID 22855269
This review is for education only and isn't medical advice. Product details are as the brand or its retailers list them. Talk to your doctor before starting any supplement.