The 19 obese participants ate the same number of calories on both diet plans - but lost slightly more weight on the low-carb diet - but most likely because they lost more water. However, the low-fat diet helped shed more of the body fat that damages health.
In fact, almost twice as much body fat melted away on the low-fat diet, the journal Cell Metabolism reports.
Researcher Kevin Hall, of the National Institute of Diabetes and Digestive and Kidney Diseases, said "not all calories are created equal when it comes to body fat loss". "While people may have been more excited to see greater weight loss with the carb restricted diet, most of this weight was from water, not fat," he added.
He cautioned against making "sweeping conclusions" about how to slim and Dr Hall simply advises slimmers to find a diet that suits them.
Susan Jebb, professor of diet and population health at Oxford University, said: "The best diet for weight loss is the diet you can stick to."
... and try high-protein breakfast
A breakfast packed with protein can stop chubby teenagers putting on more weight and reduce their hunger pangs, say experts.
Researchers found that a meal with 35g of milk, eggs, lean meats or Greek yoghurt also stopped them overeating later in the day and curbed the blood sugars that can lead to diabetes. University of Missouri scientists say the findings are important for youngsters who would normally skip the first meal of the day.
Teenagers were found to put on weight after a "normal-protein" breakfast of milk and cereal, according to the study published in the Journal of Obesity and the Journal of International Obesity.
- Daily Mail