Popular culture likes to muddle the process of losing weight. In a lot of cases, it’s as simple (not easy, mind you) as eating right and occasionally exercising. For some people, however, no amount of weight loss tips can erase the fact their body is wired to be stubborn. A new study suggests overcoming this default setting may be possible.
Everyone’s cells take a different amount of time to complete their necessary reactions. This length of time is known as a person’s basal metabolic rate (BMR). A greater BMR means the cells are producing more energy, which ultimately means foods are digested faster and broken down for use — metabolized, basically. When the BMR diminishes, more energy is required to assist the cells’ poorer function to avoid unused calories being stored as fat. In the everyday world, this comes from the foods we eat and the exercise we get. Now science believes it can lend a hand.
The intervention involves a key protein known as (ahem) nicotinamide N-methyltransferase, or NNMT. The protein helps process vitamin B3 in the body and has been linked to certain types of cancer and Alzheimer’s disease. Scientists at Beth Israel Deaconess Medical Center have found an alternate use: regulating energy metabolism in fat tissue. When NNMT levels in mice were high, obesity and diabetes were common. When they were reduced, the mice grew leaner and lost their diabetes.
What ultimately makes this possible is the body’s futile cycle — a crisscrossing of opposing cycles that produces a net effect of zero, with the exception of heat lost in the form of energy. This is important because it means scientists can manipulate a subject’s futile cycle and produce more energy externally. When the research team reduced NNMT levels, a separate group of molecules, known as polyamines, revved up cellular reactions.
"What's interesting about the polyamines is that the process of building and degrading them creates a biochemical cycle in which energy is used up,” explained co-author Dr. Daniel Kraus in a statement. “This is a futile cycle."
If the team can translate its findings into human models, a treatment for obesity could be possible. Right now, nearly 35 percent of the American public is obese, according to the Centers for Disease Control and Prevention, and rates have been climbing for decades. As we put on weight, our metabolism slows. Poor diet and lack of exercise begin to mimic, and sometimes amplify, the effects of bad genetics.
At that point, hopping on the elliptical for a half hour may help, but the climb is much further uphill than it once was. And for the morbidly obese — people who can barely walk on their own, let alone jog around the block — anti-obesity treatments, such as liposuction and lap band surgery, become their only options. With the current research, surgery may not necessarily be the next step.
“Anti-obesity therapies could be of tremendous help, and NNMT looks to be a promising target for future therapeutic development,” said senior author Barbara Kahn. “Furthermore, because obesity is associated with an increased incidence of Alzheimer's disease and certain cancers, disease states in which NNMT is also elevated” interventions may also “be beneficial in managing these other devastating conditions."
Source: Kraus D, Yang Q, Kong D, et al. Nicotinamide N-methyltransferase knockdown protects against diet-induced obesity. Nature. 2014.