The craving for carbohydrates when suffering a headache stems from the fact that many people commonly experience headaches from low blood flow to the brain and scalp muscles.
The low blood flow is due to an imbalance of the autonomic nervous system that is commonly associated with insulin resistance, obesity, diabtes and high blood pressure.
The carbohydrate cravings (as well as salt cravings) come about because carbohydrate consumption (especially processed carbs – think Red Bull) results in an increase of the amount of blood pumped by the heart (cardiac output), a squeezing effect of the arteries in our limbs (increased peripheral resistance) and a sudden release of adrenaline (catecholamine) from our adrenal glands. The sum total of all these effects is an increase in blood flow to the brain and scalp muscles and the increased blood flow alleviates some of the symptoms.
The headache pain is primarily due to low blood flow to the scalp muscles and often the neck (known as Coat Hanger Pain). Patients may also be experiencing fatigue, poor mental acuity, sleepiness after meals and occasional lightheadedness when standing.
The cravings are the brain’s learned behavior that carbs (as well as salt) will transiently increase brain blood flow and relieve the symptoms somewhat. It’s a Pavolian reflex – our subconscious brain senses the increase in blood flow from carbohydrates, learns this association and commands us to eat carbs when brain flow is again suboptimal.
This is the real driving force behind many of your cravings. The headaches are just a more prominent symptom of the same poor blood flow.
Low cerebral blood flow is also the reason why pregnant women will crave “pickles and ice cream” during pregnancy. This is really a craving for salt and carbohydrates to relieve the fatigue and foggiheadedness (“Mommy Brain”) from poor brain blood flow that is common during pregnancy.
The solution? Increase your pickles (salt) intake for a few weeks while reducing your ice cream (carbohydrate) intake and the blood flow to the brain will normalize, the headaches will resolve and your carbohydrate cravings will disappear.