A long time ago, when I was in graduate school, I read a book called Sugar Blues. The book argued that over-consumption of refined sugar contributes to the onset of diabetes. Two claims follow from that argument: first, that refined sugar acts as a type of poison in our bodies, and second, for many individuals, Type 2 diabetes is a preventable disease.

Sugar Blues, first published in 1986, appeared when many people did not yet recognize the bad effects of refined sugar. We knew it caused tooth decay, but we did not know a lot about its effects on the rest of the body. Now a book titled Suicide by Sugar, published in 2009, does not sound too alarmist. We recognize that diabetes, certain kinds of obesity, and other health problems result from sugar addiction.

Here is the problem. We’re so accustomed to regulating addictive, harmful substances – drugs, alcohol, tobacco – that we now have a movement to place sugar in the same legal framework. Even as the bad effects of these regulations become more and more plain, people who feel comfortable about the efficacy of government regulation want to see sugar added to our list of controlled substances. If that happens, the day will come when government classifies a birthday cake as a controlled substance.

A classical liberal will say that we all need to let individuals exercise some personal responsibility about what substances we allow into our bodies. We can’t permit public officials – who have power to treat possession of certain substances as a crime – latitude to jail people who want to ingest things that are bad for them. We do not hire our public servants to exercise that kind of control over us.

Here arguments related to social medicine spring forth. People who favor public regulation of harmful substances suggest, “Don’t bother us with classical liberalism. That is nineteenth century thinking – you know what we think of classical liberals in the the twenty-first century. We have a much bigger set of considerations to think about: medical costs.” That’s correct: when people bear medical costs collectively, every harmful thing individuals do to themselves becomes a matter for social control. In principle, that control extends to what you eat, and how you eat.

Under social medicine, we all benefit collectively when most people are healthy, and we all suffer collectively when too many people are not. Therefore the incidence of obesity, heart disease, head injuries – or any harmful condition we might prevent or ameliorate – becomes a matter for social control. According to this line of thought, if we can prevent bad health outcomes through public regulations, we should do it.

If you want to enjoy some cake at your daughter’s birthday party, for instance, you’ll pay a tax on it. If you want to overeat on Thanksgiving, exercise too little, and continue overeating the rest of the year, we will enact a legal regime that discourages you from that kind of self-destructive behavior. We have a social obligation to discourage you, because now your self-destructive behavior affects everyone else’s welfare. Your gluttony – and the costly effects of your obesity – raise the price of health care for everyone.

Ninety some years ago we declared possession of alcohol a crime, and we saw the effects. Today we declare possession of many substances, including marijuana, a punishable crime. We readily see the effects of that legal regime, both here and in countries like Mexico and Colombia. After familiar experiences like these, how can we regulate sugar, a move that would give government control over our diet?

Honestly, some anti-sugar advocates consider apple juice nearly as harmful as Coca-Cola and other carbonated drinks sweetened with sugar. They say that the sugar in apple juice is over refined, that it raises blood sugar levels unduly, and that we have to keep it away from our children. If you regulate apple juice and other fruit drinks, why not fruit? Under those rules, the Food and Drug Administration might decide which fruits are good for us, and which ones not.

A long time ago I stopped drinking lemonade because it has so much sugar in it. I cut apple juice, too: it’s sugar content is high and it metabolizes quickly. Someday I may have to stop drinking orange juice for the same reason, though I hope not because I truly love that stuff. No matter the drink, I can make my own judgments about my body’s reaction to the sugars in these substances. I certainly do not want a government agency to decide whether or not it is good for me. The idea that government might control my diet with taxes, prohibitions and other restrictions seems unimaginable to me.

Suppose you had to secure a prescription from your dietitian to purchase raisins or other dried fruits high in sugar. Suppose the birthday cake you want to buy for your son or daughter costs twenty-five dollars because the tax on sugar is so high. Suppose a judge could send obese people with health problems to sugar treatment centers to address their addictions. Is that what we want from social medicine?

We have seen recently how imperatives of social medicine revive apparently settled issues and long dormant fault lines. The latest disagreement involves contraception. The Catholic church protests a new regulation. Advocates for women respond. In an instant, we hear Rush Limbaugh call a woman who testifies before Congress a slut. What elicits this invective? The woman argued that employers and schools should provide health benefits that include contraceptives. Long settled issues about personal choice become divisive again because government enacts certain requirements regarding access to birth control.

Do we want to see this kind of divisiveness extend to our diets? How much argument about personal choices can we stand? Another way to ask this question is, how much control over personal choices do we want to hand over to public authorities? Do we want the sugar content of particular foods to become a matter of public regulation? Do we want to make obese people more socially outcast than they already are? We put people who ingest cocaine in jail. Would we also force chronically obese people into some kind of detention if they refuse to comply with dietary restrictions specifically intended to prevent obesity, diabetes, and other conditions that cost a lot to treat?

We already argue constitutional issues related to mandatory health insurance. We will continue to do that, as we ought to do. We also encounter social issues related to mandatory health insurance, which intentionally pools health care resources and costs. As we have seen, these social issues crop up everywhere. When we spread costs and benefits of each individual’s state of health, we open up a lot of possibilities for social control.

These possibilities lead well intentioned health advocates to declare sugar so harmful we ought to regulate and restrict it. The problem with this argument is not that sugar is benign, or just a little harmful. It is not benign. As an addictive substance, refined sugar does substantial harm. That does not mean we should treat it the same way we treat alcohol and drugs. To make sugar a controlled substance would be an enormous mistake. It would extend social control over personal choices beyond anything we have yet seen.