Berberine: banned in the EU, on sale in Switzerland

The Swiss paradox: allowed here, banned next door

The European situation

In the European Union, berberine as such cannot be used in food supplements. Preparations containing it have therefore been withdrawn from the market there. That is why French or German consumers try to obtain it elsewhere, often online.

The Swiss situation

In Switzerland, berberine remains permitted in food supplements as plant bark or root, with usual amounts of the order of 500 mg, one to three times a day. So this is not a vague tolerance: it is a difference of framework between two neighbouring sets of rules, producing different shelves on either side of the border.

What that means in practice

Two things. First, the availability of a product says nothing about how ordinary it is: a substance can be on sale here and judged too active elsewhere. Second, the reverse is also true: some substances sold freely in the European Union are banned in Switzerland, which raises the question of online purchases in both directions.

What 46 randomised trials show

The reference meta-analysis

A systematic review brought together 46 randomised controlled trials of berberine in people with type 2 diabetes, alone or in addition to usual treatments^[1]. It is the largest body of evidence available on this molecule, and it concerns objectively measured parameters, not impressions.

The results on blood sugar

Compared with control groups, berberine was associated with a fall in HbA1c of around 0.7 points, in fasting blood sugar of around 0.9 mmol/l and in blood sugar two hours after a meal of around 1.3 mmol/l^[1]. Markers of insulin resistance also improved.

The results on lipids and weight

In the same analysis, triglycerides, total cholesterol and LDL fell, while HDL rose slightly. Body mass index decreased by around one point^[1]. The authors conclude there is solid evidence of efficacy, particularly when berberine is used as an add-on to a treatment rather than in its place.

The caveat that changes the reading

Where these trials come from

This is the point enthusiastic articles systematically leave out. To build this body of evidence, the authors searched eight databases, four of them Chinese: CNKI, SinoMed, Wanfang and VIP^[1]. A significant share of the included trials therefore comes from a single publication area, where berberine is part of the traditional pharmacopoeia.

Why that matters

This is not an argument for dismissing the work, and the authors took the quality of publications into account. But when a body of evidence is concentrated on one region and one therapeutic tradition, the question of publication bias arises: positive results are statistically more likely to be published there than neutral ones. Confirmation by large independent trials conducted elsewhere is still awaited.

The right way to conclude

Neither “it does not work” nor “it is proven”. The honest wording is this: a substantial body of evidence suggests a real metabolic effect, in a medically supervised setting, with a need for independent replication. That is very different from what the pages selling it promise.

The risks the authorities flag

An active profile means a risk profile

The French food safety agency issued an alert on supplements containing berberine. It recommends that children, adolescents, pregnant and breastfeeding women, and certain at-risk groups avoid it, including people with diabetes and those with liver or heart conditions.

The effects reported

The risks mentioned are gastrointestinal upset, low blood sugar, low blood pressure, and numerous drug interactions. This last point is the most underestimated: a substance that acts on the metabolism of medicines can change the effect of treatments taken for other reasons, including those with nothing to do with blood sugar.

What laboratory work shows about the mechanism

Preclinical work sheds light on the origin of these interactions. In cell culture and on rat liver microsomes, berberine strongly induces a liver enzyme, cytochrome P450 1A2, which takes part in breaking down many medicines: its activity was multiplied fivefold in cells^[2]. Changing that enzyme means changing the speed at which the body clears other treatments.

These results come from the laboratory and from animals, not from trials in humans, and should therefore be read as a plausible mechanism rather than a clinical demonstration. The same authors note a point that qualifies things in both directions: taken orally, berberine has extremely low bioavailability, so much so that the induction did not appear by that route in animals^[2]. That poor absorption tempers the promises as much as the fears.

The practical consequence

If you take any long-term treatment, the question of berberine arises with your doctor or pharmacist, not alone in front of a screen. The logic is simple: the more measurable effects a substance has, the more reasons it has to interact with something else.

“Natural Ozempic”: where the nickname comes from

A shortcut with no basis

The nickname comes from an association of ideas: berberine acts on sugar metabolism, the GLP-1 family of medicines does too, so one would replace the other. The reasoning does not hold. The mechanisms are different, and no direct comparison allows berberine to be placed in the same category of effect, particularly on weight.

What the observed BMI fall says

The meta-analysis reports a fall of around one point of body mass index in people with diabetes^[1]. That is measurable, but very far from what the treatments it is compared with produce, and it concerns a specific population under medical follow-up. For someone without diabetes, no data support a slimming promise.

The Swiss authorities’ warning

The Confederation has also warned about fake slimming products presenting themselves as natural alternatives to injectable treatments. Berberine has become a convenient selling point in that context, which partly explains the state of the online offering.

Spotting what is wrong in the online offering

The warning signals

Search for “berberine” and you will land first on slimming patches, fake comparison sites and articles written to sell. Three signals should raise a flag: a “test” site that tests nothing and points to a single product, a numerical weight-loss promise, and the complete absence of any mention of drug interactions.

What common sense looks like

A seriously presented product states its exact composition, the plant part used, the content per dose, the groups who should avoid it and the known interactions. The absence of that information is not an oversight, it is a commercial choice. In Switzerland, a supplement must also meet the requirements of the ordinance that applies to food supplements.

Frequently asked questions