The Claim
Acute caffeine intake during total sleep deprivation has no significant effect on endothelial-dependent or endothelial-independent cutaneous vascular conductance.
What the research says
Supports is higher
Support is ahead, but a single strong opposing study can change this.
These are independent scores, not a percentage. Higher-grade studies count more, so a single strong opposing study can outweigh several weaker ones.
When people are completely deprived of sleep and consume caffeine, their skin blood vessel responses to signals from the endothelium and direct stimuli do not change significantly.
See the scientific wording
Acute caffeine intake during total sleep deprivation does not significantly alter endothelial-dependent or -independent cutaneous vascular conductance, suggesting its effects on blood pressure are not mediated by changes in microvascular reactivity.
Caffeine blocks signals that normally tell blood vessels to relax, causing them to tighten and raise blood pressure. This happens even when the tiny blood vessels in the skin cannot respond better or worse to signals that should make them open or close. The pressure rise comes from the tightened vessels elsewhere in the body, not from the skin's blood vessels losing their ability to open.
What the research says
1 studyCaffeine raises blood pressure when you're sleep-deprived, but this study found it doesn't make your tiny blood vessels worse at opening up — so caffeine must be boosting blood pressure in some other way, not by clogging up your blood vessels.
Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.