Violent crime rates have been steadily falling across the U.S. over the past three decades, defying the doomsday predictions of politicians, social scientists, police officials and many other observers.

Despite an ever-rising population; continued drug trafficking and abuse; and recurrent economic recessions, criminal activity has been dropping.

According to Justice Department statistics, on a per capita basis, the murder rate has plunged from a peak of 10.2 (per 100,000 inhabitants) all the way down to 4.8 in 2010. Thus, the incidence of homicides has been cut by more than half.

The frequency of forcible rape peaked in 1992, when 42.8 such acts were reported for every 100,000 inhabitants to 27.5 in 2010.

Broadly speaking, the incidence of all violent crime has plunged from 758.1 per 100,000 inhabitants in 1991 to 403.6 in 2010.

The Los Angeles Times reported that if the 1992 murder rate had remained, 170,000 additional people would have been killed since then.

Sociologists and criminologists have a proposed a number of reasons behind the bewildering drop in wrongdoing – including the easing of the crack cocaine epidemic, tougher police tactics, stiffer prison sentences by judges, a higher number of imprisoned inmates, an aging population, and even abortion, among others.

But the reality is that no one really knows why.

I propose a wholly new reason to explain (or partially explain) the dramatic reduction in crime: obesity.

Perhaps it is only a coincidence, but the drop in violent crime has roughly occurred concurrently with a spike in obesity.
According to the Centers for Disease Control (CDC), about 36 percent of all American adults and 17 percent of children (below aged 19) were obese in 2010.

When one includes people who are simply overweight, the numbers are even more stunning – almost 70 percent of men and women are overweight or obese, while almost one-third (32 percent) are overweight or obese.

These figures, while leveling off has remained steady for about the past decade.

Moreover, obesity rates are even higher among the poor and racial minorities (blacks and Hispanics). Almost 60 percent of black women are overweight or obese, while nearly 45 percent of Hispanic women are. Among black and Hispanic kids and teenagers, between one-fourth and one-fifth are fat. (The corresponding figures for whites is 14 percent).

In New York City, where I live, the bulk of violent crime has traditionally been committed by poor black and Hispanic youth (upon victims of similar demographics).

On a purely anecdotal basis, I have noticed that many black and Hispanic youth in the city are overweight. Indeed, it's not at all uncommon to see a 15-year old boy or girl who is in excess of 300 pounds.

It's a depressing and disturbing sight – I understand the spike in obesity over the past few decades can be attributed to junk food consumption and sedentary lifestyles.

According to a report from the CDC, about one-fifth (20.7 percent) of schoolchildren (which includes teenagers) are obese in the city – this figure is actually down slightly from a few years ago.

Although I can't really prove it, nor can I find any corroborating scholarly evidence to support my assertion (yet), I believe there must be a link between falling criminality and rising obesity.

Overweight teenagers and young adults simply do not have the strength or stamina to commit as many violent crimes as those who are healthier and stronger. Yes, anyone can shoot a gun, but it is highly unlikely that an overweight person could repeatedly exert the energy required to be an active felonious criminal (the kind who end up in prison and in Justice Department statistics).

Keep in mind, I am not “celebrating” this at all, nor am I ridiculing these overweight kids. I think obesity is a disaster that will impart long-term health implications (not to mention create extraordinary long-term health care costs) for millions of Americans for at least the next two generations.

A friend of mine from India came to visit New York for the first time ever and she was struck by how “commonplace” it was to see overweight people here. She was puzzled as to why so many folks in the wealthiest country on the planet did not have access to healthy food and did not properly exercise (given the amount of leisure time available in the U.S.) She said she felt the same compassion for obese Americans that she felt for starving Indian beggars suffering from malnutrition – in a sense, both of these disparate groups are victims of society’s inequality and exploitation. She even made a remark suggesting that obese people are just as ”helpless” and the indigent in India (despite their vast difference in physical appearance).

It was, in fact, he observations, that led me to my theory that crime is declining as so many people are getting fatter and unhealthier in the U.S.

Alas, I would much rather live in a society in which the scourges of criminal violence and unhealthy eating are both eliminated.