The human body is an amazing piece of machinery. Especially when thinking about our DNA and genes. We all have a basic knowledge of what genes are. We get them from our parents and they decide what we look like, they decide if we are better suited as a powerlifter or marathon runner, and they may even impact how healthy we are.
I think, however, that most people believe our genes are set when we are born and that’s that. We can’t do anything to change our genes, right? That’s sort of accurate. Sure we have the genes we have, but there is another factor to consider called “gene expression.” You see, not all of your genes are active. In other words, only a portion of your genes actually do stuff at any point in time. A recent study in the Nutrition Journal posed the question: just how much can we ourselves impact the genes we have?
Depending on the things you do, genes will activate or deactivate to compensate. Exercise, for example, will activate genes that are necessary for developing strength, size, or endurance. In this study, researchers looked at diets and how they affect gene expression.
Two diets were compared in the study – one the researchers called the “Prudent” dietary pattern and the other called the “Western” dietary pattern. The names seemed a bit biased at the start to me. The diets were characterized by high intakes of fruits, vegetables, and whole grains for the former, and high intakes of refined grains, sugars, and processed meats for the latter.
When they compared the diets of normal people to each diet they discovered the difference in gene expression was huge. Over 2,000 transcripts that determine gene expression were different in men who scored at each end of the Prudent pattern, and over 1,000 were different in women. For the Western pattern, the differences between men and women were smaller, and women actually had a bigger difference in gene expression, with over 1,100 different transcripts compared to just over 1,000 for men.
So simply that there are differences in expression is meaningless. However, the researchers speculate this difference in gene expression probably alters the risk of chronic disease. In other words, and without much controversy, a crappy diet makes you more susceptible to disease. The interesting bit here is that some of that risk may come from the actual activity of your genes.
To critique the study, the part about genes that make disease more likely being activated is not what they studied, but rather the actual numbers of genes between dietary types. Another issue for me was their characterization of the diets. There’s a lot more to nutrition than how many vegetables you eat versus how much sugar you eat. Also, both diets compared a high grain content to a low grain content. Some people avoid grains in their diet altogether, and I’d like to see a similar study looking at a paleo style diet, high in healthy meats and vegetables.
It is interesting that what we do alters how our genes work. And it’s good to know that no matter who our parents are we still have a lot of control over our own health and fitness.
1. Annie Bouchard-Mercie, et. al., “Associations between dietary patterns and gene expression profiles of healthy men and women: a cross-sectional study,” Nutrition Journal 2013, 12:24
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