Let’s recall some important information about food and our genes. In a previous post, we learned that every substance we eat, breathe or put on our skin enters our blood or lymph system and washes over our genes. These substances can directly affect our health by turning healthy genes ON and unhealthy genes OFF (or vice versa).
This was a HUGE discovery that proved our health is not necessarily determined by our family health or disease history. And, since the early 1990s, nutrigenomics (the study of how nutrients alter genes) has taught us more and more about nourishing our bodies to live long, healthy lives!
So, which foods can boost your genetic health? Why, fruit and veggies of course!
Growing research has identified many nutrients and natural chemicals in produce that have a positive effect on our genes. One of the best-described examples of food nutrients impacting our genes is the relationship between folate and the methylenetetrahydrofolate reductase gene. This gene contains the DNA code to produce methylenetetrahydrofolate reductase (a.k.a. MTHFR enzyme), a critical enzyme used by the body in many metabolic processes. Stay with me – I know this is science-heavy but it’s super important!
One critical function of the MTHFR enzyme is to convert homocysteine to methionine. Homocysteine is a harmful byproduct of normal metabolic reactions whereas methionine is an essential amino acid critical for healthy digestion, liver function and more. Elevated levels of homocysteine in the blood increase the risk for many health conditions, including vascular disease and premature cognitive decline. Not good!
To properly convert homocysteine to methionine, MTHFR needs folate, an essential vitamin. Folate is found primarily in leafy greens, bananas, oranges and cantaloupe. Without enough dietary folate, MTHFR doesn’t function to the best of its ability in lowering homocysteine levels.
The methylenetetrahydrofolate reductase gene is gaining more and more attention from researchers due to the high number of people carrying a mutated version of it. There are over 40 different mutations, but in essence if you carry a mutated version of the gene your ability to convert homocysteine to methionine is impaired. Now, combine an MTHFR mutation with low intake of dietary folate and you are at risk of having high levels of homocysteine. But there’s good news – people with the MTHFR gene mutation who consume lots of dietary folate and/or an activated form of folate can counteract the problem and keep their homocysteine levels normal. (Astley, pg. 11)
This is just one of the many examples of how nutrients found in fruits and vegetables have a positive effect on our epigenome, or the expression of our genetic material.
Other important natural chemicals that have gene-altering properties are called phytonutrients, which are found in all plant-based foods with the highest levels available in fruits and vegetables. Phytonutrients are the compounds that give fruits and vegetables their colors and protect them from bacteria, viruses and other predators. Commonly talked about phytonutrients include beta-carotene and lypocene.
Science has found that humans use these compounds in the same way plants do – to protect us from illness. We do this by altering gene expression (i.e. turning on and off certain genes). For example, carotenoids like beta-carotene have been shown to minimize the expression of breast cancer-related genes. Similarly, many other phytonutrients have been studied for their ability to inhibit cancer metastasis (the spread of cancer from one organ to another).
These findings are AMAZING and put the power of altering your health in your hands, not the hands of your ancestors.
So, how much produce do we really need to make a positive impact on our health?
I believe in an approach called bio-individuality, which means that every person is unique and requires a diet unique to them. Despite this, I think that the “Harvard My Plate” recommendations for making half of your plate full of fresh fruits and vegetables are a good guideline.
Here are some simple tips to incorporate more gene-altering produce onto your plate:
- Crowd out processed white potatoes (i.e., French fries, tots) with sweet potatoes and winter squashes.
- Serve dinner with two veggies instead of one.
- Mix in leafy greens whenever you can. Add spinach to scrambled eggs or hearty greens to soups and stews.
- Make double batches of veggies so you can snack on the leftovers.
- And lastly, buy enough produce! Five servings per day equals 35 servings per week (times the number of people in your household). Your grocery cart should be full of produce!
Astley, S. B. (2007). An introduction to nutrigenomics developments and trends. Genes & Nutrition, 2(1), 11–13. doi:10.1007/s12263-007-0011-z
Meadows GG. Diet, nutrients, phytochemicals, and cancer metastasis suppressor genes. Cancer Met. Rev. 31(3):441-454, 2012.
Holt, S., Paterson, N. (Producers). (2006). Ghost in your genes (DVD). Boston: WGBH.