Matcha, a powdered green tea, ameliorates the progression of renal and hepatic damage in type 2 diabetic OLETF rats.

Yamabe N1, Kang KS, Hur JM, Yokozawa T.

2009 Aug, 12

Abstract

Matcha, a powdered green tea produced by grinding with a stone mill, has been popularly used in the traditional tea ceremony and foods in Japan. Matcha is well known to be richer in some nutritional elements and epigallocatechin 3-O-gallate than other green teas. In our previous study, epigallocatechin 3-O-gallate exhibited protective effects against renal damage in a rat model of diabetic nephropathy. In the present study, we investigated the preventive effects of Matcha (50, 100, or 200 mg/kg/day) on the progression of hepatic and renal damage in type 2 diabetic Otsuka Long-Evans Tokushima Fatty (OLETF) rats. OLETF rats were orally administered Matcha for 16 weeks, and we assessed biochemical parameters in the serum, liver, and kidney and expression levels of major products of advanced glycation end products (AGEs), N(6)-(carboxylmethyl)lysine (CML) and N(6)-(carboxylethyl)lysine (CEL), receptor for AGE (RAGE), and sterol regulatory element binding proteins (SREBPs)-1 and -2. Serum total protein levels were significantly increased by Matcha administration, whereas the serum albumin and glycosylated protein levels as well as the renal glucose and triglyceride levels were only slightly or not at all affected. However, Matcha treatment significantly lowered the glucose, triglyceride, and total cholesterol levels in the serum and liver, renal AGE levels, and the serum thiobarbituric acid-reactive substances levels. In addition, Matcha supplementation resulted in decreases in the renal CML, CEL, and RAGE expressions as well as an increase in hepatic SREBP-2 expression, but not that of SREBP-1. These results suggest that Matcha protects against hepatic and renal damage through the suppression of renal AGE accumulation, by decreases in hepatic glucose, triglyceride, and total cholesterol levels, and by its antioxidant activities.

Reference

https://www.ncbi.nlm.nih.gov/pubmed/19735169

Green Tea and Diabetes Management

Medically reviewed by Peggy Pletcher, MS, RD, LD, CDE on February 29, 2016 — Written by Anna Schaefer

green tea and diabetes

Nearly 10 percent of people in the United States have diabetes, according to the American Diabetes Foundation.

When you have diabetes, life becomes all about regulating your blood sugar to stay healthy. And while many must turn to medication and insulin injections, there is evidence to suggest that drinking green tea could make diabetes management easier.

Several studies have pointed to green tea as a potentially effective method of controlling diabetes, and even improving insulin sensitivity. Just how it works isn’t completely clear, but it’s believed catechins within the tea — also responsible for its anticancer and heart health benefits — may be responsible.

How Diabetes Works

When you eat foods with carbohydrates, they are digested into sugar. In response, the pancreas releases insulin to help cells absorb glucose to be used as fuel. However, when you have diabetes, the process is hindered.

People with type 2 diabetes have cells that are desensitized to insulin, which is known as insulin resistance. This, and the fact that the pancreas often stops releasing enough insulin, makes their blood sugar levels difficult to control.

Type 1 diabetes is an autoimmune disease; the cells of the pancreas that produce insulin are attacked and killed by the body’s immune system, and simply do not produce insulin at all.

Most studies on the effects of green tea in people with diabetes have focused on type 2 diabetes, as it is more common, accounting for 90 to 95 percent of the diabetes seen in the United States.

Green Tea and Diabetes Prevention

There are indications that green tea can reduce the risk of developing diabetes. According to one study in Japan, people who drank six or more cups of green tea daily were 33 percent less likely to develop type 2 diabetes than people who drank just one cup per week.

Another study found that people who drank green tea consistently for a period of 10 years had smaller waist circumferences and lower body fat levels, showing that the tea may play a role in reducing obesity risk.

Green Tea and Diabetes Management

But tea’s benefits don’t stop at prevention. For people already diagnosed with diabetes, green tea may be able to help manage blood sugar levels.

According to a comprehensive review, green tea consumption is associated with decreased fasting glucose levels and A1C levels, as well as reduced fasting insulin levels, which are a measurement of diabetes health. While not all studies have shown these positive results, green tea has still been shown to be beneficial in other ways.

The Pacific College of Oriental Medicine suggests that the antioxidant activity of polyphenols and polysaccharides are to credit for these benefits. These same antioxidants are credited with anticancer, cholesterol lowering, and blood pressure management benefits.

Making the Most of Green Tea

If you have diabetes and want to reap the potential benefits of green tea, steer clear of additions 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 Chinese tea ceremonies. It is 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.

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