“A single night of 3-4 hours of sleep has detrimental effects on health.”

The most reliable sources are the NHLBI (Sources 1, 3) and NCBI (Source 2) with perfect 1.0 authority scores, plus high-authority medical institutions like UCLA Health, Stanford Medicine, and Yale Medicine (0.8-0.9 scores) - these sources consistently confirm that single nights of sleep deprivation produce measurable detrimental effects including elevated blood pressure, impaired memory/attention, and reduced emotional control. While some sources focus on chronic effects, the experimental evidence from NCBI showing blood pressure increases after 3.6 hours of sleep, combined with multiple independent medical authorities documenting acute cognitive and cardiovascular impacts, establishes that the claim is mostly true with strong source support.

Source 2 (NCBI) provides direct experimental evidence that one night of 3.6 hours sleep increases blood pressure in healthy young males, and Sources 5, 7, 8, and 11 corroborate that single-night sleep deprivation produces measurable impairments (elevated blood pressure, memory/attention deficits, emotional dysregulation, hippocampal damage)—these are detrimental effects even if temporary, making the logical chain from evidence to claim sound despite the opponent's valid point about scope limitations. The claim is mostly true: the evidence logically supports that a single 3-4 hour night produces detrimental effects, though the proponent slightly overgeneralizes from a narrow experimental sample and the opponent correctly identifies that "detrimental" conflates temporary impairment with lasting harm—a minor inferential gap that prevents a higher score.

The claim omits critical context about the distinction between temporary physiological changes and lasting health damage: while Source 2 (NCBI) documents acute blood pressure increases from 3.6 hours of sleep and Sources 5, 7, 8, and 11 confirm single-night cognitive and cardiovascular impairments, Source 6 (Cleveland Clinic) emphasizes that severity depends on duration, and none of the sources establish whether these acute effects constitute clinically significant "detrimental" harm versus reversible adaptive responses. The claim is mostly true because the evidence does show measurable negative physiological and cognitive effects from a single 3-4 hour night (elevated blood pressure, impaired memory/attention, reduced emotional control), which reasonably qualify as "detrimental effects on health," though the framing leaves ambiguous whether these are transient disruptions or meaningful health damage—a distinction the opponent correctly identifies but which doesn't fully negate the documented harms.