Sugar has recently becoming a major – if not the major – culprit in the growing obesity problem in the United States. More studies are showing the unpleasant realities of how much sugar Americans consume, and just how unhealthy it is for us to do so. Of course, there’s been a lot of finger-pointing in the sugary drink debate, but the bottom line is that we’re drinking too much. The solution isn’t completely clear, but some governments are beginning to step in, to try to address the problem themselves.

A recent large study shows how sugar consumption can interact with our genes to make us even more prone to obesity. The authors looked at data from over 33,000 participants in three different large-scale studies: the Nurses' Health Study, the Health Professionals Follow-up Study, and the Women's Genome Health Study.

People who were genetically predisposed to obesity had about twice the risk of actually being obese if they drank one or more sugary drink per day. In other words, drinking a lot of sugary beverages “amplifies” the effects of one’s genes.

They looked at their average consumption of sugary drinks and divided the subjects into four groups -- those consuming just one drink per month; those consuming one to four servings per month; two to six servings per week; and one or more sugary drink per day. They also studied the genomes of the participants to see who carried genes that increase the risk for obesity, and, of course, calculated their body mass indices (BMIs).

Those subjects who were genetically predisposed to obesity had about twice the risk of actually being obese if they drank one or more sugary drink per day. In other words, drinking a lot of sugary beverages “amplifies” the effects of one’s genes. This is a fascinating finding, since it underlines the ways in which nature and nurture interact to create our state of health.

The study comes at a time when many are debating both what’s “causing” the rise in obesity, and what its solution may be. New York City’s Department of Health, for example, has supported a ban on large-sized servings of sugary drinks in certain venues. Thomas A. Farley, M.D., M.P.H., the Commissioner of the NYC Department of Health and Mental Hygiene, just released a statement highlighting the issues and the steps New York will take to address them.

Since 1970, Farley says, our caloric intake has increased by a whopping 200-600 calories per day. “Although it is unclear how important changes in physical activity are to the surge in obesity prevalence, it is quite clear that this increase in calorie consumption is the major cause of the obesity epidemic—an epidemic that each year is responsible for the deaths of more than 100,000 Americans and accounts for nearly $150 billion in health care costs.”

Not coincidentally, Americans’ consumption of sugary drinks has tripled since the 1970s, and serving size of these drinks has skyrocketed. In the 1960s, Farley points out, a typical serving was 6.5-8 ounces; today it is much larger, at anywhere from 20 to 64 ounces.

The government has no choice but to address the problem, wrote Farley, who blames clever marketing from the beverage companies for part of it. "How should government address the health problems caused by this successful marketing of food? To do nothing is to invite even higher rates of obesity, diabetes, and related mortality."

New York City has proposed a variety of ways to address the sugary drink problem. One is to enforce a one-cent-per-ounce tax on sugary drinks, says Farley. The city also supports prohibiting the use of food stamps for the purchase of the drinks. And most talked about is the ban on the sale of sugary drinks in containers larger than 16 ounces in venues like stadiums, movie theaters, street carts, and many restaurants and fast food joints. Though Farley encourages the beverage industry to do its part voluntarily, he does point out that because the companies have shareholders’ profit in mind, there’s only so much they’ll do.

Time will tell how the sugary drink debacle will play out. As consumers, we can do our part, by making the switch from soda and sports drinks to water and low-sugar beverages. Though most people can’t have genetic profiles done, most probably know from their family histories whether they’re predisposed to obesity or not – and if you are, making smart food and drink choices will matter all the more.

The first study was published in the New England Journal of Medicine. Farley’s statement was published in the Journal of the American Medical Association.