In the US, two-thirds of adults and one-third of children continue to be affected by overweight or obesity despite two decades and billions of dollars' spent in public health efforts. In the last decade, public health has stepped up its call for greater emphasis on environmental and policy interventions, including active designs in urban planning and restrictions on food marketing to children, to incentivize healthy behaviors and disincentivize less healthy ones. However, there has been little success in policy change to prevent obesity. Voters in Berkeley, CA recently passed a one-cent-per-ounce soda tax, but a similar measure was defeated by voters in San Francisco, CA, which joins 30 other municipalities to date in opting not to adopt such a policy. Analysts have attributed the defeat in San Francisco, in part, to the lack of outreach to low-income and minority communities. Indeed, the lack of public mobilization in relation to obesity prevention was extensively discussed in a recent paper. No other contemporary movements have shifted public opinions more effectively and more rapidly than the gay marriage movement in the United States, which has been unfolding in parallel to efforts to prevent obesity. In this commentary, we describe how the gay marriage movement has succeeded so far in hopes of providing insight to the field of obesity prevention.