To burn fat and help lose weight, various studies recommend drinking tea. However, to lose calories, would it perhaps be better to drink it cold? This was the question posed by a team of researchers in the Faculty of Science and Medicine of the University of Fribourg in a study supported by the Swiss Cardiology Foundation.
By comparing the cardiovascular and metabolic responses of young adults to a caffeinated tea made with yerba mate leaves, a tea which is very popular in South America, the researchers at the Laboratory of Integrative Cardiovascular and Metabolic Physiology arrived at the conclusion that the cold tea could be more effective for losing weight.
The subjects drank 500 millilitres of this caffeinated tea (without sugar), over two different days and in random order. It had to be drunk in the space of 5 minutes, either at a temperature of 3 or of 55 degrees. During the following 90 minutes, a number of variables were continually measured: arterial pressure, heart rate and blood flow, as well as oxygen consumption and fat oxidisation. The results were then compared with the same variables measured during the half hour before the subjects drank the tea.
The study was led by Claire Maufrais, Delphine Sarafian, as well as Professors Abdul Dulloo and Jean-Pierre Montani, and demonstrated that the increase in energy expenditure is twice as great with cold tea (+ 8.3%) than with hot tea (+3.7%). Moreover, cold tea promotes fat oxidisation and reduces the metabolic load on the heart. If this result is confirmed when the tea is consumed over a longer time, then drinking cold caffeinated tea could turn out to be useful within a weight loss program.
This study was published in Frontiers in Physiology.