Heat rash, also called miliaria, is a skin irritation pattern that develops when sweat ducts become blocked or sweat becomes trapped beneath the skin surface during periods of excessive heat, humidity, friction, or reduced airflow. Small raised bumps, redness, itching, prickling sensations, and localized inflammation commonly occur on the neck, chest, back, under clothing, and skin folds where sweat accumulation is greatest. The condition is associated with impaired sweat evaporation, local inflammatory signaling, hydration imbalance, skin barrier stress, and irritation of superficial epidermal tissue. Eccrine sweat glands normally help regulate body temperature by moving water and electrolytes to the skin surface. During prolonged heat exposure, heavy sweating, or occlusive clothing use, sweat ducts may become obstructed, causing sweat leakage into nearby tissue. This can stimulate inflammatory mediators, cytokine activity, oxidative stress signaling, and local skin irritation. Heat stress may also increase reactive oxygen species production within skin tissue while weakening epithelial barrier integrity and hydration stability. A whole food plant-based dietary pattern emphasizing water-rich fruits, vegetables, herbs, seeds, and mineral-containing whole foods may help support hydration-electrolyte balance, antioxidant defense systems, epithelial barrier integrity, and normal inflammatory regulation. Watermelon, cucumber, celery, romaine-lettuce, tomato, orange, strawberry, blueberry, chia-seeds-whole-dried, and green-tea-brewed provide hydration-supportive nutrients, potassium, vitamin C compounds, carotenoids, flavonoids, anthocyanins, catechins, and polyphenols involved in skin resilience and oxidative balance. Vitamin C-containing foods may help support collagen structure and epithelial repair systems associated with skin barrier maintenance. Polyphenols from blueberry, strawberry, and green tea are associated with antioxidant protection pathways that help regulate oxidative stress generated during heat exposure. Lycopene from tomato and carotenoid compounds from orange-colored fruits and vegetables are linked to skin photoprotection and cellular defense activity. Potassium-rich plant foods may help support fluid balance and electrolyte regulation associated with sweat production and heat adaptation. Reducing highly processed foods, excess sodium intake, and inflammatory dietary patterns may help support hydration efficiency and skin recovery during periods of heat stress. Breathable clothing, improved airflow, hydration, and avoidance of excessive heat accumulation are also important supportive measures. Whole plant foods naturally provide water, fiber, minerals, vitamins, and phytochemicals without added oils, dairy products, or heavily processed ingredients that may contribute to inflammatory burden or fluid imbalance.