When the biologist Daniel Lieberman suggested in a public lecture at Harvard this past February that exercise for everyone should be mandated by law, the audience applauded, the Harvard Gazette reported. A room full of thin affluent people applauding the idea of forcing fatties, many of whom are dark, poor and exhausted, to exercise appalls me. Government mandated exercise is a vicious concept. But I get where Mr. Lieberman is coming from. The cost of too many people getting too fat is too high.

I live in Nashville. There is an ongoing rivalry between Nashville and Memphis. In black Nashville, we like to think of ourselves as the squeaky-clean brown town best known for our colleges and churches. In contrast, black Memphis is known for its music and bars and churches. We often tease the city up the road by saying that in Nashville we have a church on every corner and in Memphis they have a church and a liquor store on every corner. Only now the saying goes, there’s a church, a liquor store and a dialysis center on every corner in black Memphis.

The billions that we are spending to treat diabetes is money that we don’t have for education reform or retirement benefits, and what’s worse, it’s estimated that the total cost of America’s obesity epidemic could reach almost $1 trillion by 2030 if we keep on doing what we have been doing.

WE have to change. Black women especially. According to the Centers for Disease Control and Prevention, blacks have 51 percent higher obesity rates than whites do. We’ve got to do better. I’ve weighed more than 200 pounds. Now I weigh less. It will always be a battle.

My goal is to be the last fat black woman in my family. For me that has meant swirling exercise into my family culture, of my own free will and volition. I have my own personal program: walk eight miles a week, sleep eight hours a night and drink eight glasses of water a day.

I call on every black woman for whom it is appropriate to commit to getting under 200 pounds or to losing the 10 percent of our body weight that often results in a 50 percent reduction in diabetes risk. Sleeping better may be key, as recent research suggests that lack of sleep is a little-acknowledged culprit in obesity. But it is not just sleep, exercise and healthy foods we need to solve this problem — we also need wisdom.