A review of studies related to obesity and sugar has found specifically reducing fructose (as in high fructose corn syrup) intake results in dramatic improvements to metabolism in as little as two weeks, much faster than it it takes for weight loss to become apparent.

The review, published in The Journal of the American Osteopathic Association (JAOA), found that keeping the simple sugar fructose, particularly high-fructose corn syrup, out of diets can help avert health issues including obesity, fatty liver disease and type 2 diabetes. Fructose accelerates the conversion of sugar to the fat associated with these conditions, researchers noted. Their review summarized the results of several carefully controlled studies, finding a link between high consumption of sugar, in particular fructose, and increased fat synthesis in the liver.

The JAOA review found the metabolism of fructose to be particularly damaging to the body. Compared to glucose, fructose activates different metabolic pathways in the body that convert it to fat up to 18.9 times faster and store it in the body as weight. At the same time, the brain thinks the body is starving and becomes lethargic and less inclined to exercise.

“Fructose provides no nutritional value and isn’t metabolized in the brain. Your body converts it to fat, but doesn’t recognize that you’ve eaten, so the hunger doesn’t go away,” explains Tyree Winters, DO, an osteopathic pediatrician focused on childhood obesity. “Many young patients tell me they’re always hungry, which makes sense because what they’re eating isn’t helping their bodies function.”

What this means in practical terms: Cut out the processed foods and drinks. High fructose corn syrup is found in 75% of packaged foods and drinks, mainly because it is cheaper and much sweeter than raw sugar.

“If we cut out the HFCS (high fructose corn syrup) and make way for food that the body can properly metabolize, the hunger and sugar cravings fade. At the same time, patients are getting healthier without dieting or counting calories,” Dr. Winters says. “This one change has the potential to prevent serious diseases and help restore health.”

Once people have put on a significant amount of weight and developed eating habits that rely on packaged and processed foods with high fructose corn syrup, change can be daunting. Historically, physicians have told patients to restructure their diet and start exercising heavily, with a plan to check back after a month or more. That approach rarely works, researchers say, as seen by the ever-growing obesity epidemic.

Instead, Dr. Winters suggests checking blood work about two weeks after patients agree to begin limiting their sugar intake to help patients see clear benefits for their effort.

“That single change in diet improves metabolic results in less than two weeks. Imagine the power of doing a ‘before and after’ comparison with a patient, so they can see for themselves that their health is improving. Seeing those results, instead of just stepping on a scale, can motivate them to keep going,” Dr. Winters explains.