Recent studies are challenging the accuracy of the long-held practice of counting calories to lose weight, but there may not be much of a difference after all.
Rob Dunn, an assistant professor in the Department of Biological Sciences, publicized these studies in an article he wrote for the Sept. 2013 issue of Scientific American.
In the article, some researchers proposed that foods not digested contain fewer calories than what consumers may read on food labels because the body does not absorb those foods’ nutrients.
But according to Jim Croom, a professor of comparative nutrition and physiology, a majority of these foods are plant-based and high in fiber because stool forms when people do not digest the food they eat and need to remove it as waste.
Studies referenced in the article also suggested that raw food contains fewer calories than cooked food, especially food heavily processed in factories, because cooking it changes the structure of the product.
Bacteria living in our intestines also affect how the body absorbs calories, Dunn wrote in the article. Higher populations of firmicutes, a type of bacteria, may contribute to obesity because they help break down the food, thereby releasing its calories.
Sarah Ash, a professor and coordinator of the undergraduate nutrition program, said the theory is interesting, but less compelling as a significant cause for obesity when compared to the reasoning that obese people consume too many calories and don’t expend enough of them.
“The question is, does that matter?” Ash said.
Ash said the differences in bacterial populations could result from obesity, or they might contribute to obesity.
National Public Radio published an article Wednesday that explored the relationship between diet and microbial populations in the gut. In the article, though, researchers based the connection on an “inflammatory response,” not calories, Ash said.
Ash said she questions how much of an effect intestinal bacteria has on weight because one of the studies cited in the article pointed to an association between a lack of diverse bacteria and an increased risk of Type 2 diabetes, heart disease and cancer.
Researchers could not find eight crucial types of bacteria in subjects who lacked sufficient microbes, but the future creation of a supplement may replenish the bacteria, according to the NPR report.
Regardless, the findings should not change how people eat, Ash said.
“A supplement cannot replace a proper diet because the bacteria might not succeed in an environment without the food they thrive on,” Ash said.
She said the research on counting calories should not affect diets either.
“It does not change anything that we would recommend to people,” Ash said, as plant-based foods like fruits and vegetables as well as fiber-rich foods are already considered important to a healthy diet.
Even so, the importance of calories cannot be left out of the equation for losing weight.
“Overall, there is a direct correlation between burning calories and a given weight,” Croom said.
People need to be more aware of the calorie content found in the foods they are eating, Ash said.
“I think a lot of people really are clueless about this,” Ash said. “It’s amazing we aren’t bigger than we are because it’s so easy to consume calories.”
Diet alone, though, is not enough to lose weight, Croom said.
“The body senses the decrease in food intake and lowers its metabolic rate,” Croom said. “A lot of people get really discouraged from that.”
To combat this effect, people need to change their exercise routines as well as eat a healthy diet, according to Croom
Other important aspects of the weight-loss process include portion control, choice of food and how much water people drink, Croom said.
Environmental factors, such as those who have a genetic predisposition to obesity, and the consumption of drugs like antidepressants, make the task of losing weight even harder, Croom said.
“It’s a huge, huge challenge, and everyone is different,” Ash said.
Dunn declined to comment on this article.
