I gained three pounds the other week. Puzzling, because I played tennis 10 times in 12 days. Should have burned more calories. Normally I play 4-6 times in two weeks. I wondered if it was all the peanut butter and jelly sandwiches I was eating—maybe 1000 calories a sandwich. Or the pumpkin cake gift I finished in a week.

Within two weeks, I had cut back on dessert and skipped a few meals, lost the three pounds and was back to the same 175 pounds I carried when I graduated high school.

But a therapist I spoke with said most people gain back the weight they lose…especially obese people. They are too tempted by the tasty foods available to them.

Then today I read this article that really wonders why people gain it back. “Is this a failure of willpower or of technique? Was our chosen dietary intervention—whether from the latest best-selling diet book or merely a concerted attempt to eat less and exercise more—doomed to failure?

“Since the 1960s, nutrition science has been dominated by two conflicting observations. One is that we know how to eat healthy and maintain a healthy weight. The other is that the rapidly increasing rates of obesity and diabetes suggest that something about the conventional thinking is simply wrong.

In 1960, fewer than 13 percent of Americans were obese, and diabetes had been diagnosed in 1 percent. Today, the percentage of obese Americans has almost tripled; the percentage of Americans with diabetes has increased sevenfold.

Meanwhile, the research literature on obesity has also ballooned. In 1960, fewer than 1,100 articles were published on obesity or diabetes in the indexed medical literature. Last year it was more than 44,000. In total, over 600,000 articles have been published purporting to convey some meaningful information on these conditions.

It would be nice to think that this deluge of research has brought clarity to the issue. The trend data argue otherwise. If we understand these disorders so well, why have we failed so miserably to prevent them?…”

All these studies, all these papers, and people keep gaining weight! So much for the impact of knowledge on some irrational human behavior. But what the author went on to say is that it is not yet certain what diets are necessary to lose weight—or which foods created the gain. So take your best guess and keep trying…