Is obesity a disease? Or is it a result of bad lifestyle choices?
Opinions were split about 50:50 among the attendees at a recent Cleveland Clinic Medical Innovation Summit on Obesity, Diabetes, and the Metabolic Crisis. Then the speaker after the informal poll (a show of hands) said, "Obesity is 80 to 90% heredity, exceeded only by height" in its genetic cause.
That speaker was Jeffrey Friedman, who discovered leptin in 1994 and recently received a Lasker prize. The Lasker is considered a harbinger of a Nobel Prize.
Friedman went on to show slides of identical twins. The body builds of the identical twins were the same: if one twin was fat, so was the other. This was also true of twins raised apart.
Body builds of nonidentical twins were often different, despite having been raised together. And body builds of adopted children resemble those of their birth parents more than those of their adoptive parents, who would naturally influence the food that they were given.
He also described a boy who was one of the rare people who produce no leptin. Before being treated with leptin, the boy ate 1125 calories in a single test meal, about half of what an adult would eat in an entire day. At the age of 4, he weighed 90 pounds.
Then he received leptin injections and soon ate only 180 calories when offered the same meal. At the age of 6, despite being taller, he weighed only 72 pounds. A photograph showed that with the regular leptin injections he became not only normal weight, but also a bit on the thin side.
Unfortunately, most obese people do not have leptin deficiency but leptin resistance, analogous to insulin deficiency and insulin resistance, so leptin injections are not the solution for the vast majority of obese people.
In 2009, Friedman wrote an article in Newsweek arguing that obesity is genetic. He said at the conference that he received a lot of comments about the article saying, "That's crap." From the general public, this is somewhat understandable. Most people aren't able to understand scientific evidence. They read popularizations that may support their own preconceived views.
But when 50% of physicians and other leaders in the field of obesity and diabetes research think that obesity is caused by sloth and gluttony, we have a problem.
Almost everyone at the summit agreed that there's an obesity epidemic today. Philip Schauer, director of the Cleveland Clinic Bariatric and Metabolic Institute, said that the prevalence of obesity is expected to double worldwide in the next 10 years. Alex Gorsky, worldwide chairman of medical devices and diagnostics at Johnson & Johnson, said that in China, childhood obesity has increased 30 times in the past 15 years. And the Centers for Disease Control and prevention recently predicted that by 2050, 30% of Americans will have type 2 diabetes (currently 10% have been diagnosed with type 2).
Friedman appeared to support this view that there's an obesity "epidemic" today, showing a slide of a quote: "I believe no age did ever afford more instances of corpulency than our own."
