By Hafida Mazoud

Imagine a world in which we have power over our genetics, how they manifest, and how our diet determines our destiny. Epigenetics is the scientific discipline that gave this unreal theory a chance to exist, as well as giving birth to “the epigenetic diet.” However, is this diet a marketing ploy or a genuine scientific revolution?

A gene expression can be simplified to a switched “ON” or “OFF” state, as it may or may not be expressed, and the expression status of specific genes varies depending on cell type, sex or parental origin. Thus, epigenetics focuses on gene expression, specifically how our genes are turned on or off depending on what we encounter, eat, or breathe on a daily basis. Scientists are pursuing this discipline’s latest discoveries to enable us to become masters of our cellular destiny through minor changes in our lifestyles or our diets. This will result in genes modifying their expression to prevent, or even fight, cancers, metabolic disorders and neurodegenerative diseases.

Image by Dr. Peter Dynoodt & Dr. Jasper Wouters

Genes account for only 2% of our DNA, known as coding DNA, and this 2% is what determines who we are (eye colour, height, food intolerances…).This leaves 98% of our DNA (also called “junk DNA”) that is best explained by epigenetics.  This “junk DNA” is directly responsible for the expression of our genes (the 2% encoding DNA).  It is also influenced by our environment and lifestyle. If our DNA were a book, the genes would be the sentences, and epigenetics would be how the reader can interpret them. On a cellular level, RNA polymerase is the enzyme that drives this mechanism gene expression. When it detects a particular chemical, groups called methyls, it stops reading and decides not to express the gene, putting the protein or function encoded by this gene to sleep. However, scientists discovered that methyl groups are kinds of indicators that can be repositioned according to our diet, our environment, and our physical activity and other factors.

As a result of a healthy lifestyle, methyl groups on genes may be better positioned, potentially preventing the emergence of diseases to which a person is predisposed. Dr. Hardy and Dr. Tollefsbol of the University of Alabama at Birmingham have found that various food compounds, such as selenium and alcohol, could modify methylation and susceptibility to cancer in different species of animals. However, Dr. Olivia  Anderson and other researchers from University of Michigan stated that studying the connection between diet and health in human populations is obviously complicated since most people will refuse to be fed the same food every day.

Maintaining some of these epigenetic “markers” requires a constant supply of methyl groups, which can come directly from food rich in methionine, betaine or choline, while some methyl groups are also made from precursor chemicals such as folic acid. Other micronutrients are needed to transport methyl groups through the body and attach them neatly to our DNA. A deficiency in essential molecules such as zinc and vitamin B12 (cobalamin) can affect DNA methylation in the body, as shown in many studies. Dr. Yuasa and his colleagues from Tokyo Medical and Dental University have demonstrated a correlation between methylation of a cancerous gene and the consumption of green tea and cruciferous vegetable in patients with stomach cancer. A recent review by Dr. Yiannakopoulou stated that green tea catechins promote the transcription of tumour suppressor genes through modulating DNA methylation.

Photo by Brooke Lark on Unsplash

According to a quick review of scientific papers, the “Epigenetic Diet” is characterized as a diet rich in bioactive dietary components with epigenetic properties. Compounds present in tea, garlic, grapes, and soy products are used in this diet since they act as epigenetic modulators to prevent multiple tumour growth. If you’re interested in trying this diet, you can try to consume foods that have the building blocks for methylation in your body, such as leafy greens, peas, beans, sunflower seeds, and liver can be excellent sources of folic acid. Anticancer prevention therapy can be achieved using polyphenols in your diets, such as tea and curcumin, while avoiding or reducing alcohol consumption can shield you from its disruptive epigenetic effects.

Until science has a better understanding of the connection between our diet and epigenetics, the best advice is to consume a well-balanced diet rich in green vegetables and limit your alcohol consumption. Simply removing a significant amount of harmful environmental factors, such as smoking or eating an unbalanced diet, could lead to a healthier epigenome.

References

Anderson, O. S., Sant, K. E. and Dolinoy, D. C. (2012) ‘Nutrition and epigenetics: an interplay of dietary methyl donors, one-carbon metabolism and DNA methylation.’ The Journal of nutritional biochemistry, 23(8) 2012/06/27, pp. 853-859.

Occam’s corner, (2014) Epigenetics 101: a beginner’s guide to explaining everything. The Guardian. [Online] [Accessed on 05 June 2021] https://www.theguardian.com/science/occams-corner/2014/apr/25/epigenetics-beginners-guide-to-everything

Hanley, M. P. and Rosenberg, D. W. (2015) ‘One-Carbon Metabolism and Colorectal Cancer: Potential Mechanisms of Chemoprevention.’ Current pharmacology reports, 1(3) pp. 197-205.

Hardy, T. M. and Tollefsbol, T. O. (2011) ‘Epigenetic diet: impact on the epigenome and cancer.’ Epigenomics, 3(4), Aug, 2011/10/25, pp. 503-518.

Yiannakopoulou EC. (2015) Targeting DNA methylation with green tea catechins. Pharmacology. 95 (3-4):111-6. doi: 10.1159/000375503. Epub 2015 Mar 13.

Yuasa, Y., Nagasaki, H., Akiyama, Y., Hashimoto, Y., Takizawa, T., Kojima, K., Kawano, T., Sugihara, K., et al. (2009) ‘DNA methylation status is inversely correlated with green tea intake and physical activity in gastric cancer patients.’ International Journal of Cancer, 124(11), 2009/06/01, pp. 2677-2682.

Zhang, Y. and Kutateladze, T. G. (2018) ‘Diet and the epigenome.’ Nat Commun, 9(1), Aug 28, 2018/08/30, p. 3375.

Hafida Mazoud| Linkedin

SMF Blog Writer

Hafida became interested in food safety and majored in Food Science after experiencing life-threatening food poisoning. She has a Master’s degree in Food Safety and Quality Management as well as a Bachelor’s degree in Food Technologies from the Faculty of Science and Technology in Morocco. She later moved to the United Kingdom, where she pursued a second Master’s degree in Food Science and Innovation from Manchester Metropolitan University.

Hafida’s research focuses on evaluating the influence of sensory attributes such as colour on consumers acceptance of various food products like herbal tea. Hafida is a native Tamazight speaker (North African indigenous language) who also speaks Arabic, English and French. She is eager to write about topics involving food innovation, security and sovereignty.

She is currently a food consultant at the Global Diversity Foundation, where she works with rural food entrepreneurs in the High Atlas region. She is co-founder of Triple E: Educate, Empower, Exchange, an initiative that promotes the right to access information by teaching young Moroccan students how to find and apply for scholarships.

In her spare time, she enjoys spending time with her nephews and niece, going on long walks, playing video games, and cooking while listening to music.