Weight loss speeds up a little if your meals contain ginger. Nutritionists at Columbia University will soon publish in Metabolism a human study in which men burned an extra 43 calories after eating a breakfast to which ginger had been added.
The researchers did an experiment with 10 men in their late thirties. They had an average BMI of 27, so were a little overweight. The researchers gave the men a breakfast of muffins and orange juice on two occasions. The breakfast contained 595 calories, of which 85 g were carbohydrates, 25 g fat and 7 g protein.
On one occasion the men drank a glass of hot water with their breakfast, on the other occasion the researchers had dissolved 2 g powdered ginger in the water. The powder wasn't an extract of the sort you find in supplements. It was ordinary McCormick's ginger powder, like the stuff you can buy in the supermarket.
Six hours after the breakfast the researchers measured the men's energy expenditure. The figure below shows that the men burned more energy after the ginger breakfast.
After each meal, energy expenditure rises, but the increase was 43 kcal more after the men had consumed the ginger. If you did this every day – according to a simple calculation, which you aren't really supposed to do on the basis of an experiment like this – you could lose 2 kg in a year.
The powdered ginger also increased the feeling of satiety after the meal, according to the answers the subjects gave to a questionnaire they had to complete. The black bars show the scores after the ginger breakfast.
The researchers are not quite sure how ginger works. They examined the subjects' blood, but found no significant effects on the concentrations of insulin, glucose, TNF-alpha, CRP, interleukine-6, leptin, PYY, adiponectin, GLP-1 or active ghrelin.
Some found the hot water with ginger too spicy. The researchers wonder whether it wouldn't have been better to mix the ginger with a fatty food. This might have made it more palatable, and may have had even more effect: the body absorbs ginger better when combined with fat.
Nevertheless, the researchers conclude: "From a public health perspective, due to the increase in the thermic effect of food observed in this study, the use of ginger may have relevance for weight management. Moreover, effects may be increased with daily consumption."