• The U.K. has also seen its share of black market trade in banned foods, snacks, and beverages, with schools in Oxford, Dorset, and Essex reporting healthy underground markets trading in food contraband. The plots ranged from kids selling McDonald's hamburgers in playgrounds to bicycle-riding entrepreneurs hauling bags of soft drinks and milk chocolate for sale.

• Even the schools themselves are complicit. Outside that South Florida middle school mentioned earlier, vending machines stocked with high-calorie snacks and sugar-sweetened beverages adorn the waiting line for buses after classes. While biding their time in line, many of the students take advantage and load up.

Black markets evolve when demand for wildly popular products is not being met by supply. Case in point: Prohibition.

The Volstead Act, implemented in January 1920, was designed to eradicate the health and societal problems associated with alcohol consumption. The statistics say it failed. While rates initially declined, per capita consumption for the remainder of the decade actually increased by approximately 50 percent over 1919 rates. In addition, government costs to enforce Prohibition against black market activities tripled during the 1920s. And, instead of consumers switching their alcohol dollars to dairy products and other alternatives, spending on alcohol increased, as did spending on substitutes.

Bottom line: Prohibition did not improve the health of Americans as anticipated.

The primary reason for the Volstead Act's failure was that it did not focus on the real issue: excess consumption of alcohol. As evidenced by studies at the Mayo Clinic, banning is not the answer since there are actually positive benefits that accrue from moderate consumption of alcoholic beverages such as red wine, like raising good (HDL) cholesterol, reducing blood clots, and helping to prevent artery damage from bad (LDL) cholesterol.

If we are to learn anything from the temperance movement, we should turn our efforts to reducing excess calorie consumption—not applying a Prohibitionist approach in attempting to rid our society of products that consumers like and demand.

Bans—whether for sodas, candy, or books—ultimately do not serve us well. We are wasting a huge opportunity to teach calorie and portion-control lessons to our children. By prohibiting the most popular food items, one does not remove the demand. Children will find those items available in other outlets outside school guardianship.

It's time to rethink our tactics.

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