14th in Series, What’s Healthy About Tea?

Tea and Diabetes

People who are diagnosed with pre-diabetic or early diabetic symptoms are often advised that they can manage the condition with a healthy diet, weight control and exercise. Tea is one of the foods that can assist in many ways. It can replace less healthy food and drink choices without seeming like a sacrifice. A tea practice can enhance our awareness of the sensory experiences of food, adding to the pleasure of eating healthy foods and not missing the “junk”. But tea (Camellia sinensis) also provides nutritional elements that specifically support someone with the condition. So we can look at a few ways that commonly held beliefs and science both confirm that tea can help manage diabetes.

Let’s begin by saying that, when we talk about drinking tea to support treatment for Diabetes Malitus, it is unsweetened. Assume that we are not only speaking about any forms of sugar, honey, or alternative herbal sweeteners but also artificial chemical alternatives. Many teas have a natural sweetness. And we should add that the beloved high-calorie menu for traditional afternoon tea – scones, butter, jam, lemon curd, Devonshire cream – do not help manage diabetes. But, one of the wonderful things about a simple cup of tea is that it can become an important part of a healthy lifestyle in many ways and pairs with deliciously healthy foods even better than intense carbohydrates.

Blending the Camellia sinensis tea with sweet herbs and spices can produce a cup that can serve as a dessert. It can satsify an afternoon craving. In this way, it has the potential to replace more harmful foods and beverages with a satisfying and healthy alternative. So, developing an unsweetened tea preference at any age can be one element in a larger program to prevent and manage diabetes. This is the common sense aspect to considering the health benefits of tea with many different diseases. But what are some of the scientific aspects that research has considered.

It may help us better understand these benefits if we first review the nature of diabetes.

What is diabetes?

Diabetes is a chronic (long-lasting) health condition that affects how your body turns food into energy. . . . If you have diabetes, your body either doesn’t make enough insulin or can’t use the insulin it makes as well as it should.  . . .  Over time, that can cause serious health problems, such as heart disease, vision loss, and kidney disease. . . . There isn’t a cure yet for diabetes, but losing weight, eating healthy food, and being active can really help. Taking medicine as needed, getting diabetes self-management education and support, and keeping health care appointments can also reduce the impact of diabetes on your life.

Center for Disease Control Website

Can tea prevent diabetes?

Even though there has been some hype about tea and diabetes, there is no scientific evidence that drinking tea can prevent diabetes or any other disease. When we look at the results of studies, there is strong evidence that consuming tea every day can make a significant difference in overall health for many different diseases. It’s important to keep this in mind when we look some of the conclusions reached by these studies. But, in almost all cases, the results should be understood as including tea in your daily diet can help prevent diseases like diabetes. 

A Dutch study from 2009 indicates that drinking three cups of tea (or coffee) cab reduce the risk of developing type 2 diabetes by 40%. In their published results they comment that:

The current management of type 2 diabetes involves a combination of dietary plans, exercise programs, and the use of drugs, such as sulfonylureas and biguanide. Besides these conventional therapies, a growing body of evidence has indicated the role of green tea polyphenols in improving features of metabolic syndrome and subsequent risks for diabetes and its complications.

How does tea help manage diabetes?

Tea is best viewed as one of the tools in a whole-of-body program to deal with diabetes. It should not be limited to simply being a “dose of medicine” or a stand alone treatment. But even on the molecular level, the way in which tea works is providing other benefits. It is the catechin EGCG – the most abundant catechin in tea – at the core of this unseen powerhouse in our teacups. This is a polyphenol inspiring decades of research for its potential to affect human health and disease. Below are just a few of the results of contemporary research. 

Helps maintain healthy glucose levels: “black tea significantly reduces rises in blood glucose levels among both healthy and pre-diabetic adults” (Black tea consumption improves postprandial glycemic control in normal and pre-diabetic subjects: a randomized, double-blind, placebo-controlled crossover study Arisa Butacnum MSc, Rewadee Chongsuwat PhD, Akkarach Bumrungpert PhD)

Activates the insulin signaling pathway: Besides, LiuBao Tea could activate the PI3K-Akt-PPARs-GLUT2 cascade signaling pathway to improve metabolic disorders, thereby alleviating insulin resistance. These results suggest that LBT has excellent potential to become a natural functional food for the prevention of hyperglycemia and insulin resistance.  (Liubao brick tea activates the PI3K-Akt signaling pathway to lower blood glucose, metabolic disorders and insulin resistance via altering the intestinal flora.  JiangxiongZhu, MeirongWu, HuiZhou LizengCheng)

Plays a a similar role to insulin:  Several known compounds found in tea were shown to enhance insulin with the greatest activity due to epigallocatechin gallate followed by epicatechin gallate, tannins, and theaflavins. Caffeine, catechin, and epicatechin displayed insignificant insulin-enhancing activities. (Tea enhances insulin activity by Richard A Anderson 1Marilyn M Polansky)

Has a synergistic effect with certain anti-diabetic drugs:  The combination of green tea extracts, green tea polyphenols or EGCG with acarbose had a synergistic effect on α-amylase and α-glucosidase at low concentrations and the combined effect turned out to be antagonistic at high concentrations according to the Combination Index (CI) values. (Combined effects of green tea extracts, green tea polyphenols or epigallocatechin gallate with acarbose on inhibition against α-amylase and α-glucosidase in vitro.  Junjie Gao 1Ping XuYuefei WangYiqi WangDanielle Hochstetter)

Which type of tea is best to drink to help manage diabetes?

The medical research to date has studied the possible differences between green and black tea. And there have been very few studies comparing the efficacy of treating diabetes.  But studies indicate that there is very little difference between the benefits between comparable quality green and black teas. Though there are studies that show the two teas offering slightly different benefits. And more investigation into how the processing (oxidation) of tea leaves can change the benefits they offer.

Green and black tea leaves in side by side comparison

In conclusion, Diabetes is not only a common and destructive disease but it is also one that is frequently part of a complex situation where the individual is also suffering from additional issues. This can include stress, obesity, cardiac complications and dementia. One of the reasons I wanted to revise the original book, “The Everything Healthy Tea Book” with this series is to better show how tea can support our health even in situations where we struggle with multiple issues.