The study – epigenetics and tea consumption
Epigenetic changes and tea consumption
According to a team of researchers who are based at Uppsala University, consuming excessive amounts of tea may result in epigenetic changes within a woman’s body. As a result, this can increase their risk of certain diseases.
It’s not uncommon for there to be epigenetic changes and, in fact, it’s a normal part of human biology. However, there are specific factors which can influence these changes such as unhealthy eating, chemical exposure, and smoking cigarettes.
When an epigenetic change occurs, DNA may be altered regarding accessibility and structure, although your DNA may also be damaged which can lead to health complications in the future.
During this study, researchers discovered that the epigenetic changes which are caused by excessively consuming tea were taking place in genes which are involved in estrogen metabolism and cancer.
In the past, both tea and coffee have been studied by different research teams to determine the benefits and downsides to both, although no pattern between these studies has been found – thus, they are all inconclusive. However, these past studies have discovered that tea and coffee may contribute to preventing (or suppressing) tumours and cancer, as well as decreasing inflammation and positively impacting estrogen metabolism.
Coffee was also found to decrease risks of Type-2 Diabetes, Dementia, Parkinson’s, and Alzheimer’s. However, if consumed excessive amounts, coffee and tea could have the reverse effect and the risk of these diseases may raise, as well as higher blood pressure or myocardial infarction.
Tea, just like coffee, still has a lot of uncertainty surrounding how it affects our health. While the polyphenols which tea contains were previously found to decrease the risk of cancer, diabetes, and heart disease, there have also been studies which show it to be linked to increasing the risk of cardiovascular disease.
The team of researchers behind this study have stated that there has been no extensive research done regarding the analysis of how tea and coffee impact our DNA, and this would be required to say for sure if excessive tea consumption can increase disease risks among women.
Tea and coffee – beneficial or detrimental?
To improve the credibility of this study, a group of 3,096 people were studied. This team had an average age of 56 years old and were primarily used for the meta-analysis process.
After analysing the whole blood count of 421,000 CpG sites (specific DNA regions cytosine nucleotide leads guanine nucleotide, both of which are then separated by a phosphate), the team of researchers discovered that there were two CpG locations which reacted differently to tea consumption.
Specifically, CpG sites TTC17 and DNAJC16 contained genes which were already known for having connections with cancer as well as estradiol metabolism. These occurrences only happened in women – they didn’t occur in men.
That being said, the researchers also found out that women consumed a lot more tea than men did, and men drank a lot more coffee than women did. It’s safe to assume that these differences in preferred beverages could be the reason for the different results that were found.
The research team found no correlation between DNA methylation and drinking coffee in men or women.
Another limitation of this study was, that the majority of the individuals who were focused on were adults and elderly, meaning that the results of the survey wouldn’t apply to younger generations. However, while this is the case, researchers split the results from the female individuals into two groups – older than 50 and younger than 50 – and concluded that their results were identical.
There were four studies which were analysed as a part of this research project. These four studies were:
– Prospective Investigation of the Vasculature in Uppsala Seniors (804 individuals)
– Northern Sweden Population Health Study (723 individuals)
– Dutch Hunger Winter Families Study (948 individuals)
– EnviroGenomarkers Project in Italy (621 individuals)
Each of these studies’ participants were to keep records on their tea and coffee consumption on a monthly basis. During the study, blood samples were gathered from each individual and were analysed for DNA methylation.
Two types of analysis were conducted – stratified and statistical – to take into account for the differences in consumption between men and women.
At the end of this study, the researchers concluded that further extensive research would need to be done in order to account for DNA methylation that could be a result of ageing, smoking, or alcohol.