Headache is a common pain pattern involving the head, scalp, neck, vascular system, nerves, muscles, hydration status, inflammatory signaling, and sensory processing. It is not one single biological process. Headaches may be associated with dehydration, skipped meals, sleep disruption, stress physiology, neck tension, blood sugar swings, low magnesium intake, high sodium intake, alcohol exposure, caffeine withdrawal, excess screen strain, sinus pressure, environmental irritants, or broader inflammatory burden. In a P53 nutrition-support model, the focus is not pharmacy treatment, but support for the biological systems that influence head pain: hydration, electrolyte balance, vascular tone, antioxidant defense, inflammatory regulation, mitochondrial energy production, and stable glucose handling. Hydration is central because dehydration can directly contribute to headache and can also intensify other headache patterns. Foods with high water content, potassium, magnesium, vitamin C, and polyphenols support hydration and vascular balance. Low intake of magnesium-rich whole plants may reduce support for normal nerve and muscle function, vascular relaxation, and cellular energy metabolism. Magnesium is involved in ATP metabolism, neuromuscular signaling, and vascular physiology. Whole plant sources such as spinach, kale, black beans, brown lentils, chickpeas, pumpkin seeds, sunflower seeds, chia seeds, flax seeds, oats cooked, quinoa cooked, and purple barley cooked provide magnesium along with fiber and other nutrients. A whole-food plant-based headache support pattern emphasizes steady meals, low glycemic load, hydration, leafy greens, legumes, intact whole grains, fruit, seeds, cruciferous vegetables, and antioxidant-rich foods. Berries, citrus, pomegranate, apple, tomato, red bell pepper, spinach, kale, broccoli, Brussels sprouts, beetroot, cucumber, celery, watermelon, and green tea brewed provide vitamin C, carotenoids, flavonoids, anthocyanins, catechins, nitrate-containing plant chemistry, water, potassium, and fiber. These foods support oxidative balance, vascular nitric oxide signaling, gut microbiome activity, and normal inflammatory regulation. Key biological pathways include hydration and electrolyte balance, neuronal nitric oxide-cGMP signaling, AMPK signaling, oxidative phosphorylation, glutathione defense, Nrf2 antioxidant response, NF-kB signaling, prostaglandin pathway, leukotriene pathway, gut microbiome signaling, SCFA signaling, insulin signaling, and stress response. A P53 headache support strategy removes oils, meat, dairy, added sugar, alcohol, fried foods, and ultra-processed foods while emphasizing whole plants that support hydration, mineral balance, vascular function, and antioxidant protection.