Want to Lose Weight? Lose the Fructose
Consumption of fructose has skyrocketed for most Americans in recent decades. So, too, have obesity and overweight. And it’s becoming increasingly hard to deny there’s a link between the two. Of course the high fructose corn syrup (HFCS) industry vigorously denies there’s any such connection. But mounting evidence—generated through careful, objective research—begs to differ.
Most recently, scientists at the Beckman Institute for Advanced Science and Industry published research that should alarm anyone who continues to consume HFCS—and anyone listening to the propaganda routinely spewed by the HFCS industry.
Simply put, when compared calorie-for-calorie against simple glucose, fructose leads to weight gain, physical inactivity, and fat deposition. Anyone concerned about their body weight—or indeed, their health in general—would do well to avoid this stuff. According to experts, fructose now accounts for about 10% of most Americans’ daily calories. That’s primarily due to consumption of prepared baked goods and other foods, and soft drinks. Among male teenagers, the proportion of calories obtained from fructose often reaches 20% or more.
Of course, Americans are consuming more calories in general, in addition to more calories from fructose. So that’s made it more difficult to argue that the obesity epidemic is linked to fructose consumption specifically. But new research would appear to put that argument to rest. Investigators did a simple experiment. They fed two groups of identical mice two different diets. All received the same number of calories overall, but one group got 18% of their calories from glucose, while the other got an equal percentage of calories from fructose. Investigators chose 18% because it’s roughly equal to the amount of sugar being consumed by the average adolescent boy in America.
Fructose-fed mice experienced significantly greater body mass, fattier livers, and more body fat, than their glucose-fed peers. Fructose-fed animals were also less active. "The important thing to note is that animals in both experimental groups had the usual intake of calories for a mouse," said researcher, Catarina Rendeiro. “They were not eating more than they should, and both groups had exactly the same amount of calories deriving from sugar, the only difference was the type of sugar, either fructose or glucose.”
Justin Rhodes led the research team. “We don't know why animals move less when [on] the fructose diet," said Rhodes. "However, we estimated that the reduction in physical activity could account for most of the weight gain.” Investigators suspect it has to do with how the body handles the two different sugars. “Biochemical factors could also come into play in how the mice respond to the high fructose diet,” explained Jonathan Mun, another author on the study. “We know that contrary to glucose, fructose bypasses certain metabolic steps that result in an increase in fat formation, especially in [fatty] tissue and liver.”
Catarina Rendeiro, Ashley M. Masnik, Jonathan G. Mun, Kristy Du, Diana Clark, Ryan N. Dilger, Anna C. Dilger, Justin S. Rhodes. Fructose decreases physical activity and increases body fat without affecting hippocampal neurogenesis and learning relative to an isocaloric glucose diet. Scientific Reports, 2015; 5: 9589 DOI: 10.1038/srep09589