Scientists from the State Polytechnic Institute of Higher Education in Coimbra (Portugal) discovered that caffeine can slow down cerebral blood flow. Research results published at Science Direct.
45 people between the ages of 18 and 22 who rarely drink coffee participated in the study. Participants’ cerebral blood flow rate was assessed using transcranial Doppler ultrasound, an ultrasound technique used to examine blood flow to the brain. They were then divided into two groups; The first group received a single dose of 45 grams of caffeine capsule, the second group received a 120 gram caffeine capsule, and the third group received a placebo. Thirty minutes after consuming caffeine, participants underwent transcranial Doppler ultrasound again.
Caffeine appeared to reduce mean, maximum systolic, and end-diastolic cerebral blood flow velocities in participants in the first and second groups. Peak systolic velocity is the maximum speed of blood flow at the moment of contraction of the heart, and end-diastolic velocity is the same indicator at the moment of relaxation of the organ.
The effect of caffeine on the brain is to narrow blood vessels. The severity of headache decreases due to vasoconstriction. Additionally, caffeine stimulates the central nervous system, increases alertness and relieves fatigue. However, when blood vessels narrow, the speed of blood movement through them slows down. This can cause cerebrovascular accidents.
existed before listed Foods that disrupt sleep.