The findings – published in Molecular Nutrition and Food Research – reveal that epigallocatechin-3-gallate (EGCG) found in green tea help to reduce blood sugar spikes in mice fed a high starch diet.
Led by Dr Joshua Lambert from Penn State University, USA, the research team found mice fed EGCG had significant reductions of blood sugar spikes after a starchy food when compared to mice that were not fed the compound.
"The spike in blood glucose level is about 50 percent lower than the increase in the blood glucose level of mice that were not fed EGCG," explained Lambert – who added that the findings could lead to new diet strategies for people.
Lambert, who noted that the dose of EGCG fed to the mice was equivalent to about one and a half cups of green tea for a human, said EGCG was most effective when the compound was fed to the mice simultaneously with the starchy food (in this case corn starch).
For humans, he suggested that this may mean that green tea could help control the typical blood sugar increases that are brought on when people eat starchy foods, like breads and bagels that are often a part of typical breakfasts.
"If what you are eating with your tea has starch in it then you might see that beneficial effect," Lambert said. "So, for example, if you have green tea with your bagel for breakfast, it may reduce the spike in blood glucose levels that you would normally get from that food."