Evidence deep-dive

Raspberry Ketone Has No Human Trial, At Any Dose

That sentence is not a rhetorical flourish. It is the state of the literature: mice fed diets of half to two per cent raspberry ketone, two studies on a mouse cell line, and one eight-week trial of a product containing six ingredients at once.

By SodaSlim Team · Last updated November 4, 2026 · 8 min read · Evidence deep-dive · Reviewed by Dr. Schehrezade Khan, MD

What raspberry ketone is

4-(4-hydroxyphenyl) butan-2-one: the compound that gives red raspberries their characteristic smell. It is present in the fruit in tiny quantities, which is why essentially all of it on the market is made synthetically or by fermentation rather than extracted.

The reason it appears on supplement labels at all is structural. Its molecule resembles capsaicin, the pungent compound in chilli, and synephrine, a stimulant found in bitter orange. Both of those have documented effects on lipid metabolism, and the resemblance prompted researchers to ask whether raspberry ketone behaves similarly.

That is the entire origin of the ingredient. A structural similarity, a plausible question, and a body of work that never progressed to people.

The complete evidence base

Four studies. Not four of the best ones — four in total, for raspberry ketone as a weight-related ingredient.

The complete human and animal evidence base for raspberry ketone as a weight ingredient, as retrieved in the citation pass for this website.

Laying it out that way makes the shape unmistakable. Two of the four are cell studies on one mouse-derived line. One is a rodent feeding study. The fourth is in humans and tests a product containing six things.

Compare that with the caffeine literature on the same label, which includes randomised dose-response work in humans, pooled meta-analyses, safety reviews and a scientific statement from a cardiology body. The two ingredients sit on the same front panel and they are not the same kind of claim.

What the mouse study actually did

The 2005 study ran two experiments. In the first, mice were fed a high-fat diet containing 0.5, 1 or 2 per cent raspberry ketone for ten weeks. In the second, mice were given a high-fat diet for six weeks and then switched to the same diet containing 1 per cent raspberry ketone for five more.

The results were consistent: less of the weight gain the high-fat diet produced, lower liver and visceral fat weights, and lower hepatic triacylglycerol. The authors also showed increased noradrenaline-induced lipolysis in rat fat cells, with translocation of hormone-sensitive lipase to the lipid droplet, which is a specific and checkable mechanism.

It is a competent piece of work and nothing here is a criticism of it. What it is not is a finding about people.

What the cell studies show

The 2010 study found raspberry ketone increased both lipolysis and fatty acid oxidation in 3T3-L1 adipocytes, a mouse-derived cell line that is the standard model for fat cells in culture. A 2015 study on the same line found it inhibited adipogenic and lipogenic gene expression.

Cell work is how a mechanism gets described, and both papers do that job. The limits are the ones every cell study has: a concentration in a dish is not a dose in a person, a mouse cell line is not human tissue, and nothing in a culture has to survive digestion, a liver or a bloodstream.

An ingredient with a mechanism in a dish and no measurement in a person is at the beginning of the process, not the end of it.

The one human trial, and its design

The 2013 trial randomised seventy obese but otherwise healthy adults to a multi-ingredient supplement or placebo for eight weeks, alongside a calorie-restricted diet and exercise training. Forty-five completed it.

The supplemented group did better on body weight, fat mass, lean mass, waist and hip girth and self-reported energy. No adverse events or changes in clinical blood chemistry were noted between groups.

The product contained raspberry ketone, caffeine, capsaicin, garlic, ginger and Citrus aurantium. Two of those — caffeine and Citrus aurantium — have well documented effects of their own, and the trial ran on top of a diet and an exercise programme that the placebo group also followed.

So the finding is that a six-ingredient product plus diet and exercise beat placebo plus diet and exercise. That is a legitimate result about a product. It is not a result about raspberry ketone, and the paper does not claim to be one.

Why the mouse dose does not scale

The scaling column is the reason a mouse study cannot be read as a human dose. A diet of one per cent raspberry ketone is not a capsule.

The arithmetic is the point. A diet containing one per cent raspberry ketone means one gram in every hundred grams of food the animal eats. Translated to a person eating ordinary quantities, that is grams a day, sustained for weeks.

Supplement capsules in this category contain milligrams. Nobody is putting grams of an aroma compound into a once-daily capsule, and nobody should.

This is the most common quiet error in supplement marketing, and it is worth knowing how to spot it. Whenever a page cites an animal study for an ingredient, the question is what proportion of the animal's diet or body weight was used, and what that becomes in a person. The answer is very often a dose no capsule contains.

What this desk does instead

There is no page on this website that says what raspberry ketone does in a person, because nobody has measured it. The refusal is recorded in the source file and printed on the disclaimer alongside three others.

That is a deliberately awkward position for a retail desk. Raspberry ketone is one of five ingredients on a product this desk sells, and the easier route would be to describe the mouse findings warmly and let a reader draw the inference.

The reason not to is that a refusal recorded is something a reader can argue with, and a claim quietly softened is not. If a randomised human trial of raspberry ketone alone is published tomorrow, this page changes and its review date moves.

Analytical work on supplement labelling is a reminder of the other half of the problem: even where a figure is printed, declared and measured amounts can differ. An ingredient with no printed figure and no human trial is two steps from anything a reader could check.

The pattern this ingredient belongs to

Raspberry ketone is the clearest example on this label of a pattern that runs through the whole category.

• An ingredient is identified in a cell or a rodent, and a plausible mechanism is described.
• The mechanism is genuinely interesting and the animal result is genuinely real.
• It arrives on labels long before anyone has measured what it does in a person.
• The marketing describes the mechanism in the present tense, as though it were an established human effect.
• The human trial, if it ever happens, tests a blend rather than the compound.

A narrative review of supplements for weight management describes the same landscape across the category. The practical defence is a single question: was this measured in a person, and at what amount?

The same question applied to the other four names on this label is on the ingredients page, and the general version is in the metabolism supplement guide.

References