Research

Hormonal

In states of insulin deficiency (low insulin, high glucagon), elevated free fatty acids do not inhibit glucose uptake but instead stimulate endogenous glucose production (gluconeogenesis/glycogenolysis), contributing to hyperglycemia.

If you have low insulin (like in Type 1 Diabetes or severe starvation), eating fat will not lower your blood sugar by blocking glucose uptake. Instead, the body breaks down fat into glycerol, which the liver turns into more glucose, potentially raising your blood sugar levels.

GoodQualifiesHIGH confidence
In contrast, when hyperglycemia was associated with relative insulino-penia and hyperglucagonemia (study C)... lipid infusion had no effect on glucose uptake... but markedly stimulated endogenous glucose production (1.4±0.5 vs. 0.5±0.4 mg/min-kg, P < 0.005).
Eleuterio Ferrannini et al. · Journal of Clinical Investigation · 1983

Why this rating

Controlled human clinical trials.

Source

Effect of fatty acids on glucose production and utilization in man.

Eleuterio Ferrannini et al. · Journal of Clinical Investigation · 1983

DOI 10.1172/jci111133

rct · n=26Cited 1,057×
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DOI resolved against Crossref · corpus check 2026-06-10

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