Drinking, or better yet digestion and the body’s ability to absorb key elements of green tea, may play a vital role in aiding the brain to fend off the development of Alzheimer’s, and can protect against cancer. Digestion is a vital process which provides our bodies with the nutrients we need to survive. However, just because the food we put into our mouths is generally accepted to contain health-boosting properties, we can’t assume these compounds will ever be used by the body. A new study has been published that hints this ancient Chinese remedy could play a vital role in building defenses against key life threatening conditions.

Dr. Ed Okello of Newcastle University, the executive director of the university’s Medicinal Plant Research Group team and based in the School of Agriculture, Food and Rural Development explains:

“What was really exciting about this study was that we found when green tea is digested by enzymes in the gut, the resulting chemicals are actually more effective against key triggers of Alzheimer’s development than the undigested form of the tea. In addition to this, we also found the digested compounds had anti-cancer properties, significantly slowing down the growth of the tumor cells which we were using in our experiments.”

Green tea is tea made solely with the leaves of Camellia sinensis that have undergone minimal oxidation during processing. Green tea originates from China and has become associated with many cultures in Asia from Japan and South Korea to the Middle East. Recently, it has become more widespread in the West, where black tea is traditionally consumed. Many varieties of green tea have been created in countries where they are grown and these varieties can differ substantially due to variable growing conditions, horticulture, production processing, and harvesting time.

Over the last few decades green tea has been subjected to many scientific and medical studies to determine the extent of its long-purported health benefits, with some evidence suggesting that regular green tea drinkers have lower chances of heart disease and developing certain types of cancer. Although green tea does not raise the metabolic rate enough to produce immediate weight loss, a green tea extract containing polyphenols and caffeine has been shown to induce thermogenesis and stimulate fat oxidation, boosting the metabolic rate 4% without increasing the heart rate.

For this particular study, The Newcastle University team deemed it necessary to analyze the protective properties of the products of digestion, so they worked alongside Dr. Gordon McDougall of the Plant Products and Food Quality Group at the Scottish Crop Research Institute in Dundee, who developed technology which simulates the human digestive system.

Two compounds are known to play a significant role in the development of Alzheimer’s disease (AD); hydrogen peroxide and a protein known as beta-amyloid. Long considered a key player in the development and progression of AD, beta-amyloid has gradually begun to give up many secrets of its importance. Scientists have learned an enormous amount about how beta-amyloid plaques are formed and the toxic effects that these structures as well as the earlier forms of beta-amyloid have on neurons and synapses. These findings have opened up new avenues of investigation and new possibilities for therapeutic targets.

Compounds known as polyphenols, present in green tea, possess neuroprotective properties, binding with the toxic compounds and protecting the brain cells. When ingested, the polyphenols are broken down to produce a mix of compounds. Carrying out the experiments in the lab using a tumor cell model, the Newcastle team exposed the cells to varying concentrations of the different toxins and the digested green tea compounds.

Dr. Okello continues:

“The digested chemicals protected the cells, preventing the toxins from destroying the cells. We also saw them affecting the cancer cells, significantly slowing down their growth. Green tea has been used in Traditional Chinese medicine for centuries and what we have here provides the scientific evidence why it may be effective against some of the key diseases we face today. There are obviously many factors which together have an influence on diseases such as cancer and dementia – a good diet, plenty of exercise and a healthy lifestyle are all important. But I think it’s fair to say that at least one cup of green tea every day may be good for you and I would certainly recommend it.”

Okello’s team has already received funding from the Biotechnology and Biological Sciences Research Council (BBSRC) to discover whether the beneficial compounds are produced during digestion after healthy human volunteers consume tea polyphenols or if they already exist in the unconsumed product.

The full reports can be digested here: “In vitro protective effects of colon-available extract of Camellia sinensis (tea) against hydrogen peroxide and beta-amyloid (A(1-42)) induced cytotoxicity in differentiated PC12 cells.” E J Okello, G J McDougall, S Kumar and C J Seal. Phytomedicine.

Written by Sy Kraft, B.A.