Raspberry Ketones
4-(4-hydroxyphenyl)butan-2-one
A TV-famous 'fat burner' with no human evidence.
Evidence tier
No Evidence
Research weight
Not supported
Citations
13 verified / 13
Classification
Debunked
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What the evidence says. No credible human evidence supports the marketed claims — widely considered ineffective.
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No credible evidence. The claims below are what marketers assert — not what science supports. This entry is included so you can recognise it.
What is Raspberry Ketones?
Raspberry Ketones (4-(4-hydroxyphenyl)butan-2-one) is a debunked supplement marketed for fat burning & weight loss. NutriDex grades the human evidence as No Evidence. Raspberry ketones are aroma compounds that shot to fame after a TV endorsement as a 'miracle' fat burner. The hype rests on cell-culture and rodent studies using doses far beyond what any human takes. There are essentially no controlled human trials showing weight loss from raspberry ketones alone. The compound sold is almost always synthetic, not extracted from raspberries.
Marketed Claims (unproven)
✕(Claimed) fat burning & weight loss
Dosing & Compounds
Use & Legality
No effective dose established in humans; weight-loss claims are unsupported.
Active Compounds
Safety & Cautions
Limited human safety data. Often sold in stimulant blends, which carry their own cardiovascular and jitter risks. Because raspberry ketone is structurally similar to synephrine, case reports have linked it to palpitations, tachycardia, coronary vasospasm and even ventricular arrhythmia/cardiac arrest, and supplement doses vastly exceed food-flavoring levels. No demonstrated benefit to weigh against any risk. Educational only — always check with your doctor or pharmacist before combining Raspberry Ketones with any medicine.
Evidence & Risk Findings ★ 13 studies
systematic review / meta-analysis
Jazinaki 2024 (anthropometric meta-analysis)
✓ PubMed
GRADE-assessed meta-analysis of 9 RCTs (10 arms, 355 adults) found raspberry consumption produced no significant change in body weight, BMI, waist circumference, or liver enzymes (low/very-low certainty).
systematic review / meta-analysis
Jazinaki 2024 (lipid/BP meta-analysis)
✓ PubMed
Systematic review and meta-analysis of RCTs in adults found raspberry consumption did not significantly alter lipid profile or blood pressure versus control.
Systematic review/meta-analysis
Glycemic/inflammation meta-analysis 2024
✓ PubMed
A systematic review and meta-analysis of RCTs in adults found raspberry consumption significantly raised insulin (WMD 1.89 uU/mL) and lowered TNF-alpha (WMD -3.07 pg/mL) but had no significant effect on fasting glucose, HbA1c, glucose tolerance, HOMA-IR, CRP, or IL-6.
regulatory toxicology review
Bredsdorff 2015 (toxicology/safety review)
✓ PubMed
A Danish National Food Institute risk assessment found that food-supplement doses of raspberry ketone (100-1400 mg/day) are 26-368 times higher than dietary exposure and reach 56x the threshold of toxicological concern, leaving a margin of safety as low as 12 at 1400 mg, with QSAR models flagging possible cardiotoxic and reproductive/developmental effects.
RCT
NCT06681597
✓ Source
Registered single-dose human interventional study (500 mg raspberry ketone) measuring plasma FGF21 and energy expenditure at 0-6 h in adults aged 18-60; completed June 2024 with no peer-reviewed results posted as of mid-2026.
randomized controlled trial
Lopez 2013 (multi-ingredient RCT)
✓ PubMed
A randomized, double-blind, placebo-controlled trial in 70 obese adults (45 completers) of a multi-ingredient supplement containing raspberry ketone plus caffeine, capsaicin, synephrine, garlic and ginger showed greater fat-mass loss (-7.8% vs -2.8%) and body-weight loss (-2.0% vs -0.5%) than placebo, but the design cannot attribute any effect to raspberry ketone itself given the stimulant co-ingredients.
RCT
Harada 2008
✓ PubMed
Mechanistic mouse plus small human trial. Topical 0.01% raspberry ketone (structurally similar to capsaicin) raised dermal IGF-I via CGRP/sensory-neuron activation; in humans it promoted hair growth in 50% of 10 alopecia patients at 5 months and increased cheek skin elasticity in 5 women at 2 weeks (P<0.04). Supports a topical, not oral weight-loss, benefit.
Review
Reviews
✓ Source
Classed among unsupported weight-loss fads.
case report
Case report 2022 (ventricular tachycardia)
✓ PubMed
A previously healthy 32-year-old obese woman developed life-threatening polymorphic ventricular tachycardia requiring 33 defibrillations after using an OTC weight-loss supplement high in raspberry ketones, implicating it as a cardiotoxic trigger.
analytical study
Quality/authenticity analysis 2025
✓ PubMed
Multianalytical (GC-MS/LC-MS) survey of marketed raspberry ketone supplements found ~60% had label-versus-measured discrepancies, most under-dosed, with evidence of synthetic adulteration.
Study
Human trials
✓ Source
No quality RCTs show weight loss from raspberry ketones alone.
Government/authority fact sheet
NIH ODS Weight Loss fact sheet
✓ Source
The NIH Office of Dietary Supplements concludes there is no evidence raspberry ketone is safe or effective for weight loss in humans, noting only one inconclusive multi-ingredient RCT (45 completers) and that supplement doses of 100-1,400 mg/day (vs a few mg from diet) have never been evaluated for safety in people.
Preclinical
Morimoto 2005 (mice)
✓ PubMed
Effects seen only in rodents at very high doses — not replicated in humans.