The Anatomy of Violence (38 page)

We also saw earlier that
cognitive functioning is impaired in offenders. Omega-3 supplementation has been shown to improve learning and
memory in animals,
²⁵
and also improves
learning in children.
²⁶
So it’s not just that omega-3 in theory improves the brain. In practice, it makes a difference in terms of cognitive functioning—and cognitive functioning is critical for performance in school and success in life.

Omega-3 enhances both brain structure
and
function. We saw in earlier chapters that brain structure and function is impaired in offenders. So it’s perhaps not all that surprising that we find associations between the amount of fish consumed and the perpetration of violence.

You might still find this all a bit too much to believe. Surely it can’t be that simple? And correlation is not necessarily causation, right? You’re correct on both counts. But what we will see in a later chapter on treatment is that there is mounting evidence from randomized controlled trials that omega-3 is effective in reducing antisocial behavior—and such trials are as good as it gets in establishing causality and demonstrating a true and meaningful relationship.

But you’re likely still not convinced, are you? What use are these
malnutrition studies to the United States, or other prosperous nations? Look around, everyone seems pretty healthy and there’s plenty to eat. These results must be a problem only in developing countries, like Mauritius.

And you’ve got a reasonable point here. Visitors to the United States cannot help but be struck by the abundance of food and the big portions that are served up in basic restaurants. And the desserts are veritable
mountains of yumminess. You take a look around you and, well, people do look kinda big in America. Rates of
obesity are 30.6 percent for the United States and 23.0 percent for the United Kingdom, compared with 12.9 percent for Germany, 10.0 percent for the
Netherlands, and 3.2 percent for both
South Korea and Japan.
²⁷
There’s certainly no lack of sustenance over here in the United States, so what’s the deal with all the
violence?

There are three complementary perspectives to this issue. First, if you meet or see pictures of adult
murderers, it’s true that they certainly don’t look malnourished. But this belies the fact that as children some of them, like the killers
Henry Lee Lucas and
Donta Page, were surviving by rummaging around in garbage cans. Page was an unfed, malnourished, scrawny little boy when he was growing up in the ghettos around Washington, D.C. But when as an adult he raped and killed
Peyton Tuthill he weighed in at over 300 pounds. The outer appearances of adult offenders can be very misleading, hiding years of
malnutrition at a critical early juncture in life when the brain is rapidly developing.

Second, there are two types of nutrients—
macronutrients and
micronutrients. Kids in America are getting plenty of the macronutrients—carbohydrates, fat, and protein.
²⁸
But the story is different for the second component—the micronutrients that include vitamins and trace minerals, things like
iron and zinc. They are “micro” because the amounts we need every day are really small, in the order of micrograms or milligrams. Yet they are critical for the growth and maintenance of body and brain functions. At the level of micronutrients, the
World Health Organization argues that up to one half of all the children in the world have iron or
zinc deficiency.
²⁹
That’s a staggering fact.

Third, we’ve also got to factor in that there is a wide range in the “
bioavailability” of nutrients—the ability of the nutrient in question to get into your bloodstream and act on your brain. Bioavailability is influenced both by a host of genetic factors that determine how well nutrients are absorbed from the gastrointestinal tract, and also by environmental factors such as food inhibitors and enhancers. So, essentially, you can have two people with the same intake of micronutrients, but they may differ radically in terms of the degree to which those micronutrients get into their bloodstreams and act on their brains.

Once again, outside appearances and how well-fed a person appears to be can be very deceiving. Big is not better when it comes to body size and nutrition. Genes and environment, the two big gladiator arenas in
which we have been seeing
violence played out, can also starve the
brain of critical
nutrients. Given their potential importance, let’s take a brief look at these
micronutrients and the roles they may play in violence.

What are micronutrients? They include vitamins as well as important trace minerals like iron and zinc. If as a kid you had acne or if you had white spots on your fingernails, as I did, you can suspect
zinc deficiency.

Deprive mice of zinc and their aggression increases threefold.
³⁰
Even before birth, zinc deprivation during pregnancy in rats increases their offspring’s aggression.
³¹
Children and adults in the United States with
assaultive and aggressive behavior have abnormally low levels of zinc relative to
copper.
³²
A Turkish study similarly found that violent schizophrenics had lower zinc and copper ratios than nonviolent schizophrenics.
³³

Iron is another important micronutrient. Several
studies have found aggressive and
conduct-disordered children to be zinc-deficient.
³⁴
One study found
iron deficiency in a third of juvenile
delinquents.
³⁵
Preschoolers with low iron also show a reduction in positive emotions.
³⁶
This is significant because a lack of positive emotion characterizes conduct-disordered children.
³⁷

Let’s link back to the brain again to understand why these micronutrient deficiencies can predispose someone to violence. Micronutrients like iron and zinc are critical for the production of neurotransmitters and are important for brain and
cognitive development. If you reduce dietary levels of zinc and protein in rats during pregnancy, then their offspring show impaired brain development.
³⁸
Adult animals fed a zinc-deficient diet show “
passive avoidance learning deficits.”
³⁹
This is an inability to learn to inhibit a response that leads to punishment, a cognitive deficit repeatedly found in offenders who have difficulty learning from their mistakes.
⁴⁰

We can also link micronutrients to specific brain structures involved in violence. The amygdala and hippocampus, which are impaired in offenders, are packed with zinc-containing neurons. Zinc deficiency in humans during pregnancy can in turn impair DNA, RNA, and protein synthesis during brain development—the building blocks of brain chemistry—and may result in very early brain abnormalities.
⁴¹
Zinc also plays a role in building up fatty acids, which, as we have seen, are
critical for brain structure and function.
⁴²
The availability of iron in the brain, like zinc, has been shown to affect
neurotransmitter production and function.

What results in iron and zinc deficiency? It could be a lack of foods like fish, beans, and vegetables. Bear in mind that micronutrients play an important role in fetal brain development, and up to 30 percent of pregnant mothers with low socioeconomic status are believed to be iron-deficient. Smoking during pregnancy also impairs the transportation of zinc from the mother to her fetus,
⁴³
depriving the fetal brain of a key nutrient. We have already seen that smoking during pregnancy predisposes a woman’s offspring to adult violence.

Amino acids are also important because they are what proteins are made out of. Eight of our twenty-two amino acids are essential because our bodies cannot produce them.
Animals fed diets reduced in one of these—
tryptophan—become aggressive, while high-tryptophan food reduces their aggressive
behavior.
⁴⁴
When tryptophan is experimentally reduced in men and women,
⁴⁵
they respond more aggressively when provoked.
⁴⁶
Reversing that scenario, when tryptophan is enhanced, aggressive behavior is reduced.
⁴⁷

Low tryptophan likely increases aggression because it impairs the brain’s ability to inhibit responses that we should not make. Brain-imaging research has shown that reducing tryptophan reduces functioning in the orbital and
inferior regions of the right prefrontal cortex when subjects try to refrain from making a response to a stimulus.
⁴⁸
We saw earlier that this underneath part of the prefrontal cortex is
functionally and
structurally impaired in offenders. Because
serotonin is synthesized from tryptophan, the amino acid likely predisposes someone to reactive aggression by lowering brain serotonin, the neurotransmitter we saw in
chapter 2
to be depleted in impulsive violent offenders.

Where does tryptophan come from? Foods like
spinach, fish, and turkey. We see that omega-3 from fish could have a calming effect on aggression. In addition to fish, you might also tell your kids to eat their spinach—even if Popeye is not exactly the best role model for nonaggressive behavior.

Sugar rush. Many of us have experienced it. We eat a ton of high-carbohydrate foods and drinks and then feel an energy rush that can
make us feel able to shoot for the stars. Then we can feel a little agitated, get light-headed and on edge, and make a crash landing. That’s what was claimed when
Dan White killed the mayor of San Francisco,
George Moscone, along with the city supervisor and
gay-rights activist
Harvey Milk.

Dan White was down in the dumps. Life wasn’t working out too well. Having gone from serving in the
Vietnam War to working as a police officer and then as a firefighter, he was familiar with high-
risk life adventures. But his latest risky venture, a potato restaurant, wasn’t working well, and he was out of money. He had resigned his position on the San Francisco Board of Supervisors—a position he had gained with strong union support from both firefighters and the police.

He had also fallen out with Harvey Milk, who was supporting the establishment of a juvenile detention center that had been proposed by the
Catholic Church and was located in White’s district. Now, while Dan White was a Roman Catholic, he was dead set against having the detention center in his district. He also had a gripe with gays, and Harvey Milk was gay. White had resigned from his political position to focus on his potatoes, but with their failure he went back to Mayor Moscone to regain his position. Moscone was in favor, but Milk was against White’s reappointment.

In a fit of
reactive aggression, White took a
gun and entered San Francisco City Hall through a window to avoid the metal detectors. He went into Mayor Moscone’s office and begged him to restore his position. Moscone refused, so White shot him dead. He then went into Harvey Milk’s office and shot him dead too.

Enter the
Twinkie. At his trial, White’s defense team and their psychiatrists argued that he was suffering from depression and had immersed himself in an orgy of
junk foods and drinks packed with refined sugar. Bad diet could influence his mood. White was a white working-class heterosexual all-American Catholic who had fought for his country and once saved a woman and her baby from a fire. The jury was made up of predominantly white working-class people who shared White’s values. Some openly wept when they heard the pressure he was up against in his life. Instead of first-degree murder and the death penalty, he was found guilty of voluntary
manslaughter and received a prison sentence of seven years and eight months.

The San Francisco gay community went
nuts. Even Acting Mayor
Dianne Feinstein proclaimed: “Dan White has gotten away with murder. It’s as simple as that.”
⁴⁹

White’s defense had been buttressed by $10,000 that the police had raised for him. The result was the “White Night Riots.”
⁵⁰
A crowd of 1,500 quickly gathered that night in the predominantly gay
Castro District, where Milk had lived. It grew to an ugly 3,000 who descended onto City Hall and tore the place apart.
⁵¹
Police cars were set on fire. After establishing order at City Hall, police retaliated by going into bars in the Castro area and beating up gays. Sixty-one police officers and over a hundred gays were hospitalized for injuries. Dan White eventually committed
suicide.

All this because of a little Twinkie?

Not quite, but near enough. Twinkies themselves—sponge cakes with cream filling—were never actually brought up at Dan White’s trial, and the term “Twinkie Defense” was a phrase invented by the press. But junk food was brought up at the trial. Could it really contribute to diminished rational thought, as the defense argued? The claim certainly caught on rapidly after the trial. As one protestor put it to reporters as he was setting fire to a police car on that White Night, “Make sure you put in the paper that I ate too many Twinkies.”
⁵²

White’s behavior may or may not have been influenced by junk food, and even if it did contribute to the homicides, we are hard-pressed to view this as an excuse—either an excuse for Dan White’s outrageous actions or, indeed, an excuse for the reactions of the local community. But if there is a mechanism at play here with respect to aggression, the likely candidate is refined carbohydrates. A number of
studies have claimed that dietary changes aimed at reducing sugar consumption reduce institutional antisocial behavior in juvenile offenders. Some of these claims are striking. For example, one early controversial study—a two-year double-blind controlled study of twelve- to eighteen-year-old delinquents—obtained a 48 percent reduction in disciplinary offenses after diets were altered in order to reduce refined carbohydrates.
⁵³
Experimental studies in animals have also demonstrated a causal relationship between
low blood sugar and aggression in rats.
⁵⁴