The Claim

In healthy adult humans, intravenous infusion of GLP-1 at 1.2 pmol/kg/min and insulin at 1 mU/kg/min individually induces vasodilation of the brachial artery and increases blood flow by approximately 30%, but co-infusion of both hormones does not result in a greater vasodilatory effect than either hormone alone, suggesting non-additive actions on conduit artery function.

Source: GLP-1 and Insulin Recruit Muscle Microvasculature and Dilate Conduit Artery Individually But Not Additively in Healthy Humans

What the research says

Supports is higher

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

Supports
54score
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.

How it works
1 study reviewed
In plain English

When healthy adults get infusions of two hormones—GLP-1 or insulin—each one widens a major arm artery and boosts blood flow by about 30%. But when both are given together, they don’t widen the artery any more than just one alone, meaning they don’t add up.

See the scientific wording

In healthy adults, intravenous GLP-1 (1.2 pmol/kg/min) and insulin (1 mU/kg/min) each cause dilation of the brachial artery and increase blood flow by approximately 30%, but their combined infusion does not produce a greater effect than either hormone alone, indicating non-additive vasodilatory actions on conduit arteries.

What the research says

1 study
  1. Study: GLP-1 and Insulin Recruit Muscle Microvasculature and Dilate Conduit Artery Individually But Not Additively in Healthy Humans

    The study found that both GLP-1 and insulin widen arm arteries and boost blood flow when given alone, but together they don’t do more than either one alone — just like the claim says.

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.

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