Eat more meat and potatoes.
That was the advice of Dr. Arthur MacDonald, speaking to Congress in 1903.
Before you jump to the conclusion he was a crank I would point out MacDonald was a respected criminal anthropologist in the employ of the U.S. Bureau of Education. The author of numerous books and scientific papers, he was an advocate for the creation of an apparatus combining the pneumograph, psychogalvanometer and cardiospysmograph—what became the modern polygraph.
He was also a follower of the theories of Cesare Lombroso who believed criminals were born and could be identified by physical traits—profiling to the extreme.
As to meat and potatoes, the good doctor contended one of the reasons for an increase in crime was a decrease in their consumption and a tendency toward less solid and staple foods.
“The less cost of living and the increase of wealth, with the luxuries of the table,” he proclaimed, “have tended to overheating, which, in connection with lack of exercise, has had its evil effects and doubtless produced an additional reaction on the nervous system. When the nerves are unstrung by overpressure the will may become weak, depression and pessimism set in and loss of self-control follow with its consequent abnormal actions leading on to crime and other social evils.”
In that same address to Congress MacDonald averred automobiles, electric cars and the telephone were equally to blame for the increase in crime, insanity, suicide and other forms of abnormality. He argued these inventions caused people to exercise less and think more. This, MacDonald said, puts an abnormal strain on the nervous system as compared with the muscular system. “States having the greatest intelligence and education also exceed in insanity, suicide, juvenile criminals, nervous diseases and paupers.”
So, if we want to bring crime down, all we have to do is eat more meat and potatoes and stop thinking.