Supporting what many men have long known, research shows that hiking that tie from half-mast to tight can make you feel like there isn't enough blood getting to your brain.

German researchers have reported in the journal Neuroradiology that using MR imaging to compare tie-wearing and tie-free groups of participants showed that when the tie compressed the jugular and carotid blood vessels to the head it led to a cerebral blood flow (CBF) reduction of 7.5 percent.

“In many professions, a special dress code including a necktie and a collared shirt is mandatory although little is known about the effect of this 'socially desirable strangulation', ” stated first author Robin Lüddecke and colleagues from the Division of Neurological Pain Research and Therapy, Department of Neurology and Department of Radiology and Neuroradiology at the Universitätsklinikum Schleswig-Holstein in Kiel, Germany.
That's enough to be dangerous or even fatal for those with high blood pressure, according to Big Think.

The tie-wearers all fashioned the classic Windsor style, one of the largest knots and loved by all who wear it for its ability to stay tightly in place against any but the strongest yank or other tie-entangling mishap, according to Forbes.

The 15 participants with neckties had three MR scans, one with the tie loose and shirt collar unbuttoned, one with the collar buttoned and the tie loosely pulled up snug to the “point of slight discomfort,” according to the news site, and a third scan with tie undone and collar again open. The 15 controls had the three scans as well.

Beyond the tightened-tie induced CBF drop, those with neckties saw an average decrease of of 5.7 percent even after the tie was loosened. Breaking the results down a bit, “all but 2 of the necktie-wearing subjects had a drop in cerebral blood flow with five having a greater than 10 percent decrease” according to Forbes, noting that for unknown reasons, the control group's CBF actually increased a bit during the second MR.

The news made a splash across the waters in Lancaster, California, too, where Mayor R. Rex Parris ordered city officials to look at prohibiting a tie requirement for employees.

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