Altitude sleep disruption refers to difficulty falling asleep, repeated nighttime awakening, shallow sleep patterns, restless sleep, morning fatigue, and impaired recovery associated with sleeping at elevated altitude. Reduced atmospheric oxygen pressure at higher elevations can alter nighttime breathing stability, oxygen saturation, stress signaling, circadian regulation, and autonomic nervous system balance. During sleep, oxygen delivery naturally declines slightly even at sea level. At altitude, this reduction may become more pronounced and contribute to unstable breathing patterns, increased nighttime arousal, and fragmented sleep architecture. The nervous system responds to reduced oxygen availability by increasing sympathetic activation and respiratory drive. These physiologic responses may increase circulating stress hormones such as cortisol and catecholamine-related signaling compounds. Elevated nighttime stress signaling may interfere with melatonin rhythms, sleep maintenance, vascular relaxation, and deep restorative sleep cycles. In some individuals, periodic breathing and fluctuating carbon dioxide levels may further destabilize sleep continuity and contribute to repeated awakening episodes. Evening meal composition may influence nighttime nervous system balance and sleep-related neurotransmitter pathways. Complex carbohydrate-containing whole plant foods may help support serotonin and melatonin precursor pathways by influencing amino acid transport patterns and glucose stability during overnight recovery. Slowly digested carbohydrate-rich plant foods may also help reduce nighttime stress signaling associated with unstable blood glucose fluctuations and elevated cortisol activity. A whole food plant-based dietary pattern emphasizing evening complex carbohydrates, potassium-rich fruits, magnesium-containing legumes and greens, antioxidant-rich berries, and hydration-supportive foods may help support normal circadian signaling, oxygen utilization, endothelial circulation, hydration balance, and nighttime nervous system stability. Foods such as oats, brown-rice-cooked, banana, sweet-potato-orange, tart berries, pumpkin-seeds-dried, spinach, chickpeas, kiwi, and green-tea-brewed contain compounds associated with circadian support, nitric oxide regulation, antioxidant defense systems, neurotransmitter synthesis, vascular relaxation, and mitochondrial energy support. Hydration status is also important at altitude because respiratory water loss increases in dry mountain environments. Mild dehydration may worsen fatigue, increase nighttime heart rate, impair circulation, and contribute to sleep disruption. Potassium-rich fruits and vegetables, magnesium-containing seeds and legumes, nitrate-containing vegetables such as beetroot and spinach, and antioxidant-rich polyphenol foods may help support vascular flexibility, endothelial nitric oxide activity, cellular oxygen handling, and metabolic recovery systems involved in nighttime adaptation to altitude exposure.