The Most Unhappy of Pleasures: This Is Your Brain on Sugar

By all estimates, obese people are not happy. The question is whether their unhappiness is a cause or a result of their obesity. At this point we can't say for sure, but both could be right.

The look on their faces testifies against them; they parade their sin like Sodom; they do not hide it. Woe to them! They have brought disaster upon themselves. --Isaiah 3:9

The Bible teaches us that pleasure doesn't pay. If you don't destroy yourself, then God will do it for you. Four thousand years later and the rules are still the same. The only thing that's changed is the vehicle.

When did the world become so obsessed with pleasure? Scripture argues that the goal of a righteous life is happiness, not pleasure. The Declaration of Independence affords us the right to "the pursuit of happiness," not pleasure. But pleasure has taken center stage in virtually all human pursuits. Delayed gratification is so 20th century.

Yet we are, by all accounts, not happy. You may have heard of the gross national happiness index, an indicator that measures quality of life or social progress in more psychological terms. Despite the fact that the United States has the highest gross domestic product, we score 44th on the happiness index. Who's #1? Denmark. The home of Hamlet, the most unhappy character in all of literature, the country that was overrun by the Nazis, where they freeze half the year, where they nurse one Carlsberg all night and eat rice because they can't afford a steak. Money can't buy happiness. But it sure can buy some pleasure.

Substances of abuse used to be the subject of much hand-wringing. It started with opium dens, moved to speakeasies, then to crack houses, then to "smoking permitted" anterooms. Since Nancy Reagan's "Just Say No," the war on drugs has taken a back seat, but not because it has been won. Rather, because a different war has cluttered the headlines -- the war on obesity. And a substance even more insidious, I would argue, has supplanted cocaine and heroin. The object of our current affliction is sugar. Who could have imagined that something so innocent, so delicious, so irresistible -- just one glucose molecule (not so sweet) plus one fructose molecule (very sweet) -- could propel America toward economic deterioration and medical collapse?

The brain's pleasure center, called the nucleus accumbens, is essential for our survival as a species. We learned how important it was with the introduction in 2003 and subsequent removal in 2007 of the anti-obesity drug rimonabant. This medication blocked the effect of endocannabinoids, molecules that affected the pleasure center like marijuana -- sort of like the anti-munchies. Patients lost interest in food and lost weight, but 20 percent became clinically depressed, and many committed suicide. Turn off pleasure, and you turn off the will to live.

But long-term stimulation of the pleasure center drives the process of addiction. Rich people are addicted to money, power, gambling; middle-class people are addicted to cocaine, amphetamine, caffeine, nicotine, alcohol, heroin. The poor, well, all they've got is sugar.

Pleasure is exciting. Happiness is transcendent. More importantly, pleasure is dopamine. And happiness is serotonin.

When you consume any substance of abuse, including sugar, the nucleus accumbens receives a dopamine signal, from which you experience pleasure. And so you consume more. The problem is that with prolonged exposure, the signal attenuates, gets weaker. So you have to consume more to get the same effect -- tolerance. And if you pull back on the substance, you go into withdrawal. Tolerance and withdrawal constitute addiction. And make no mistake, sugar is addictive.

By all estimates, obese people are not happy. The question is whether their unhappiness is a cause or a result of their obesity. At this point we can't say for sure, but it is entirely possible that both answers are correct. Here's how. The serotonin hypothesis argues that deficiency of brain serotonin causes severe clinical depression, which is why serotonin reuptake inhibitors (SSRIs) such as Wellbutrin and Prozac, which increase brain serotonin, are effective.

Not by chance, these medications are also used for obesity. Serotonin is made from an amino acid called tryptophan, which is the rarest amino acid in our diet. And the amino acid transporter that gets tryptophan into the brain is easily perturbed. If you're serotonin-deficient and depressed, you're going to want to boost your serotonin any way you can. Eating more carbohydrate, especially sugar, initially does double duty -- it facilitates tryptophan transport, and it generates a dopamine response for pleasure in the short-term. But as the dopamine signal down-regulates, more sugar is needed for the same effect, driving a vicious cycle of consumption to generate a pleasure that withers in the face of persistent unhappiness.

On Day 18 of his sojourn through Super Size Me, Morgan Spurlock confides that he is sick and unhappy -- then he starts eating, and he feels "great; so great it's crazy." Not crazy, just addicted. McDonald's most recent campaign says it all: "Crafted for your craving." The food industry knows what it's doing. Why don't we?

In fact, pleasure and happiness might just be opposites. As we have spent the last 30 years pursuing sugar for pleasure, we have become most decidedly unhappy. Our society has lost sight of the difference. Coca-Cola's most recent marketing tagline is "Open Happiness." Couldn't be further from the truth. As our obesity, type 2 diabetes, hypertension, heart disease, cancer, and dementia rates continue to skyrocket due to our sugar over-consumption, the idea that a bottle of Coke holds the key to happiness is nothing short of pulp propaganda.

So what is the key to happiness? Roko Belic's recent indie movie Happy traces the roots of happiness through the slums of India to the deserts of Namibia to the streets of Okinawa. And food isn't mentioned once. Rather, the ties that bind are family, community, and doing something to make the world a better place. I think back to World War II, when Denmark saved the Jews by smuggling them to Sweden. In Judaism, it's called tikkun olam. Healing the world. Just what the Bible teaches. Now there's a reason to be happy.

Image: Larina Natalia/Shutterstock.