While many people living with diabetes need oral medications and/or insulin injections, there is evidence to suggest that drinking green tea may be helpful as part of your diabetes management plan.

According to the American Diabetes Association, a little over 11 percent of people in the United States have diabetes.

Several studies have pointed to green tea as a potentially effective complement to a health-promoting eating plan that may help improve insulin sensitivity.

How green tea may work to support insulin sensitivity is not completely clear. Older studies suggest catechins within the tea — also responsible for its anticancer and heart health benefits — may be responsible.

When you eat foods with carbohydrates, they’re digested and broken down into sugar, or glucose. In response to this process, the pancreas releases insulin to help cells absorb glucose to be used as cellular fuel. When you have diabetes, this process is hindered.

People with type 2 diabetes have cells that are not responsive to insulin, a process known as insulin resistance. This, and the fact that the pancreas often stops releasing enough insulin, makes their blood sugar levels difficult to manage.

Type 1 diabetes is an autoimmune disease. With this condition, the body’s immune system attacks and kills the pancreatic cells that produce insulin. Also, these specific cells in the pancreas do not produce any insulin.

Most studies on the effects of green tea in people with diabetes have focused on type 2 diabetes, as it’s more common, accounting for 90–95% of diabetes diagnoses in the United States, per the Centers for Disease Control and Prevention (CDC).

Research indicates that including green tea as part of a Mediterranean-type eating plan may be helpful in preventing type 2 diabetes. Drinking green tea as a replacement for other sugary beverages may also reduce the risk of developing type 2 diabetes.

A recent literature review suggests that green tea may be helpful for weight loss as part of a healthy eating plan, but more well-controlled human studies are needed.

According to a comprehensive research review published in 2017, studies show some green tea benefits for those with diabetes, but the results were mixed.

The inconsistent results were possibly due to genetics, a mix of male and female participants, the type of tea leaves used, and the bioavailability of the active ingredients in the green tea leaves. The review involved analyzing global research that included human and animal participants.

For instance, research published in 2023 involving over 2,200 Chinese adults found that consuming tea resulted in reduced insulin secretion and worse insulin resistance. The research was conducted over a 5-year period.

More well-controlled human studies are needed to reach a definitive conclusion about the benefits of green tea for diabetes.

While not all studies have shown positive results regarding diabetes, green tea has still been shown to be beneficial in other ways. For example, in an unsweetened form, green tea remains preferable to sugar-sweetened beverages.

If you have diabetes and want to maximize the potential benefits of green tea, it’s important to avoid adding substances that can cause blood glucose changes. It’s best to drink the mild-tasting tea plain, instead of diluting it with milk or sweetening it with sugar.

Teabags are just fine (loose leaf is best), but if you want to enjoy a fresher, green flavor, you can buy traditional matcha green tea online and in specialty shops.

Matcha is a green tea powder, traditionally used in Japanese tea ceremonies. It’s prepared with a small bowl and bamboo whisk, though a spoon or wire whisk can work in a pinch. Because the tea is more concentrated in a matcha powder, you may reap additional benefits over bagged green tea.