Cancer and Green Tea – Sorting Through The Evidence
By now most of us have heard that green tea may have tremendous potential in terms of helping us win the war against cancer. There have been many studies that have shown that green tea has been shown to prevent the development of cancer when it is a significant part of your diet. In addition, there have even been studies that have shown that green tea may even have potential for treating cancer.
But, then occasionally you’ll find a study that makes it sound as though green tea may actually have some negative effects on our health. So, it can be easy to get confused as to whether we really should be adding green tea to our diets for health benefits or not.
Here are a few things that are known for sure.
Anti-oxidants are good for us. They combat the free radicals that are created in our bodies as we process food. When our diet is low in anti-oxidants the free radicals damage our cells and our DNA. Over time this leads to aging and disease.
Tea contains EGCG and polyphenols. These are two of the most potent forms of anti-oxidants, making tea, particularly green tea, because of its lack of fermentation, rich in the substance that protect us from aging and disease.
There are no known side effects to drinking green tea. Green tea is lower in caffeine that coffee or black tea, so it’s a good beverage choice for those who must watch their intake of caffeine. And, it’s completely natural. A simple cup of tea will have no additives, preservatives or processed substances.
Asian cultures drink a large amount of green tea and have a significantly lower than incidence of cancer, heart disease and stroke. Of course, there may be other factors in the Asian lifestyle that affect their lower incidence of disease. However, there are some statistics that are startling. For instance, nearly 75% of all Japanese men smoke, yet their risk of lung cancer and heart disease is significantly lower than that of American men.
It’s true that we still need additional research on humans to gain more conclusive evidence about green tea and its potential in preventing or treating cancer.
Many of the studies that have been conducted have been on mice. Human research takes years of follow up to be conclusive and is more difficult than laboratory research. And, there are many more factors that must be considered during human studies, such as habits and genetics.
One interesting discussion of the studies that have been performed on green tea and their results, both positive and negative, is in the National Library of Medicine. This publication gave an overview of several studies done on green tea and cancer. The breakdown looks like this.
In 5 studies on colon cancer, three concluded that it might prevent cancer, one concluded that green tea might contribute to cancer.
In 4 studies on rectal cancer, one reported that green tea could prevent cancer, but two showed that it might actually contribute to developing the disease.
In 10 studies on stomach cancer, 6 suggested that green tea might prevent cancer and 3 suggested that it might contribute to cancer. The most comprehensive study on stomach cancer reported that green tea is an effective preventer of cancer.
Nearly all studies on pancreatic and esophageal cancer suggest that green tea has a preventative effect, and most lung cancer studies have shown positive results, though there has been at least one study that reported and increased risk associated with green tea.
So, as with many other health research concerns, there is still much work that needs to be done. And, there have been a few studies that have shown a possibility that green tea might actually increase your risk of cancer. However, when you take the research as a whole, it seems probable that you’re better off drinking green tea than avoiding it.
As research continues, we’ll learn more definitive information about the level of protection that green tea can provide, and just exactly how it provides this protection. As we learn more, we’ll be better able to determine how much tea you really need to drink and on which cancers it seems to be most effective.
In spite of the few studies that have shown some negative results, overall researchers believe that green tea shows great promise in the area of cancer prevention and treatment. For centuries, Asians have used green tea to prevent and treat all kinds of illnesses, even before there was scientific research to support it.
In the mean time, there seems to be no reason to avoid green tea. It’s refreshing, has no side effects and can be a great way to lower your intake of caffeine. Keep your eyes out for the new research findings as they emerge – it’s sure to be exciting to find out all the potential that lies in green tea.