The Study
Effects of 12-Week Supplementation with Coffee Diterpene Cafestol in Healthy Subjects with Increased Waist Circumference: A Randomized, Placebo-Controlled Trial
This study is like a fair test where half the people got a special pill and half got a fake one. We saw that the real pill helped people lose a little belly fat and lowered a liver marker, but it didn't help their blood sugar. So we can say the pill caused those fat changes — but not that it stops diabetes.
Analysis score
Maximum 90 for a randomized controlled trial.
Where the score came from
Scientists gave people a purified coffee compound called cafestol to see if it could shrink belly fat and improve blood sugar, like coffee sometimes seems to do.
Where does this study sit?
Reviews of RCTs (Meta-analyses)
Max 100Randomized Trials
Max 90Reviews of Cohort Studies
Max 85Cohort Studies
Max 72Reviews of Case-Control Studies
Max 63Case-Control Studies
Max 58Cross-Sectional & Case Series
Max 50Expert Opinion
Max 573 / 100
Quality score
Participants are randomly assigned to treatment or control groups, minimizing bias. The gold standard for testing whether an intervention causes an effect.
Key takeaways
Summary
Based on the study abstract and findings.
- 1Losing 400 mL of belly fat is meaningful — it's like losing a small watermelon's volume — but without improved blood sugar, it's unclear if this reduces diabetes risk.
- 2People who took cafestol lost 0.88 kg in weight and 400 mL of belly fat, and their liver stress marker (GGT) dropped 15%.
- 3But their blood sugar and insulin sensitivity didn't change.
Score breakdown, methodology, conflicts of interest, evidence analysis & raw study data
Publication
Journal
Nutrients
Year
2024
Authors
Fredrik D. Mellbye, M. D. Nguyen, Kjeld Hermansen, P. Jeppesen, Z. Al-Mashhadi, S. Ringgaard, Søren Gregersen
Related Content
Claims (4)
Daily supplementation with 12 mg of cafestol for 12 weeks reduces gamma-glutamyl transferase levels by 15% in healthy adults with increased waist circumference, with no change in liver fat content or LDL cholesterol.
Taking 12 mg of cafestol daily for 12 weeks does not change fasting HbA1c, average blood glucose, or blood glucose fluctuations in healthy adults with higher waist circumference.
Daily intake of 12 mg of purified cafestol for 12 weeks reduces visceral fat by about 400 mL and body weight by 0.88 kg in healthy adults with increased waist circumference, without changing insulin sensitivity or glucose tolerance.
In healthy adults with increased waist circumference, taking 12 mg of cafestol daily for 12 weeks reduces visceral fat but does not improve insulin sensitivity or glucose tolerance.
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.