The International Atomic Energy Agency (IAEA) has released useful new data from its dual-labeled water (DLW) database, which provides insight into the effectiveness of exercise in encouraging weight loss.
The results are not as straightforward as you might think.
“When they sign up for weight loss training programs, most people lose a little, some people lose a lot, but a few unlucky people actually gain weight,” said John Speakman, chairman of the DLW Database Management Group and one of the study’s authors. .
According to the study, the body of people with a normal body mass index of between 18.5 and 24.9 will offset calories burned during exercise by 28 percent – meaning that only 72 percent of the calories will be lost during the day.
But with age and weight, this ratio decreases, and those with the highest body mass index will only lose 51 percent of the calories burned in exercise.
The study confirms that individuals differ in the way their bodies budget for energy expenditure, and people living with obesity may have difficulty losing weight as their bodies are effective at sticking to their fat storage.
© UNHCR / Benjamin Loyseau
More than just exercise
“There are many health benefits that can be gained by being more active and exercising, but relying on exercise alone will not help you lose weight., ”Said Alexia Alford, an IAEA nutritionist and co-author.
Guidelines for weight loss do not take into account the reduction of calories burned through other common life functions, as the body compensates for the calories burned during exercise.
“If you increase your activity, your body will compensate for it in other areas and cut down on the calories burned by breathing, digestion, tumbling and generally the body’s maintenance and function,” she explained. “This can actually make up quite a lot”.
Combining a healthy diet with a more balanced lifestyle is key to maintain a calorie deficit for weight loss, according to the co-author.
Using DLW to study a body’s total energy consumption is not new, but the high cost of oxygen-18 and the machines to measure it have kept the studies on a small scale so far.
In 2018, the IAEA was contacted by a group of DLW investigators who wanted to make their data sets more widely available, and the IAEA DLW database was developed.
Today, the database has DLW data from over 7,600 people, making it the world’s largest collection.
Free and available for researchers with defined management-approved questions, IAEA DLW Database contains information on various cases, ranging from athletes to cancer patients and people with cerebral palsy.
As most of the data comes from studies conducted in Western countries, such as the United States and the Netherlands, the IAEA seeks to expand the data set further to include Asia, Africa and Latin America.
Next year, it will launch a coordinated research project to add more countries with lower income data.
“Our database is an invaluable asset for a better understanding of how the human body works. This exercise study is a good example; whereas most DLW studies generally involve around 30 subjects, the exercise study had over 1,600, making the data very robust”, said Ms. Alford.
“The data in the IAEA DLW database is an untapped treasury, and we encourage researchers to contact us to access its contents and contribute their own datasets.”