Why do we get headaches when we skip meals?

When you skip a meal, your blood sugar levels drop, a condition called hypoglycemia. In response, your body releases hormones like adrenaline and cortisol to help raise blood sugar, and these hormones can cause blood vessels in the brain to constrict and then dilate, triggering pain signals. Additionally, low blood sugar directly affects the brain, which relies almost entirely on glucose for energy. This stress on the brain can activate pain pathways and cause the throbbing or dull ache typical of a hunger headache. Dehydration, which often accompanies missed meals, can worsen the effect. Eating a balanced meal or snack typically resolves the headache within about 30 minutes as blood sugar stabilizes.