The Claim

Twelve weeks of 12 mg daily cafestol supplementation does not improve insulin sensitivity or glucose tolerance in healthy adults with increased waist circumference, despite reducing visceral fat.

Source: Effects of 12-Week Supplementation with Coffee Diterpene Cafestol in Healthy Subjects with Increased Waist Circumference: A Randomized, Placebo-Controlled Trial

What the research says

Supports is higher

Support is ahead, but a single strong opposing study can change this.

Supports
73score
Challenges
0score

These are independent scores, not a percentage. Higher-grade studies count more, so a single strong opposing study can outweigh several weaker ones.

Cause and effect
1 study reviewed
In plain English

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.

See the scientific wording

Twelve weeks of 12 mg daily cafestol supplementation does not improve insulin sensitivity or glucose tolerance in healthy adults with increased waist circumference, despite reducing visceral fat, indicating that fat loss alone may not be sufficient to enhance glucose metabolism in this population.

Why this might work

Cafestol lowers belly fat by changing how fat cells store oil, but this fat loss does not make the body better at using sugar or responding to insulin. The liver becomes less stressed, but this also does not improve how the body handles blood sugar.

Supported mechanismbased on 1 study

What the research says

1 study
  1. Study: Effects of 12-Week Supplementation with Coffee Diterpene Cafestol in Healthy Subjects with Increased Waist Circumference: A Randomized, Placebo-Controlled Trial

    Taking cafestol for 12 weeks helped people lose belly fat, but their blood sugar and insulin response didn’t get better — showing that losing fat doesn’t always fix how the body handles sugar.

Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies

Fit Body Science verdict — we translate health claims into clear verdicts backed by peer-reviewed research.

Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.