Four grams of glucose.
Level 5 - mechanism / opinion, no new human data
Narrative review of physiological mechanisms without systematic search methodology.
PubMed 18840763 · doi:10.1152/ajpendo.90563.2008
What was done
This narrative review summarizes physiological mechanisms governing blood glucose homeostasis in humans, specifically focusing on the regulation of glucose flux from the liver to blood and from blood into skeletal muscle. The review outlines the actions of glucagon and insulin, as well as the distributed control points of muscle glucose uptake (delivery, transport, and phosphorylation).
What was found
The abstract provides a baseline physiological reference value noting that approximately 4 grams of glucose circulates in the blood of a 70 kg individual. It outlines the conceptual framework of distributed control across glucose delivery to muscle, transport across cell membranes, and intracellular phosphorylation, along with the regulatory roles of insulin and glucagon. No empirical experimental numbers or statistical effect sizes are reported in the abstract.
Why it matters
It provides a foundational conceptual model showing that glucose homeostasis depends on a distributed network of regulatory steps rather than a single rate-limiting barrier.
Limits
The abstract describes a narrative review rather than an empirical trial or systematic review; sample sizes, study selection criteria, and quantitative results are not reported.
Cited by
- supports In a human body with normal blood sugar, the entire 5 liters of blood contains only approximately one sugar cube (about 4 grams) of total dissolved glucose.