One of the most exciting additions to the world of nutrition is the field of epigenetics. Through this science, we’re learning that the effects of diet are more important and far-reaching than we thought. We used to believe that genetics meant we’re doomed to get the same conditions as our parents. Epigenetics says otherwise. It’s showing us that we can affect how our genes express themselves (whether we get diseases or not) through diet and lifestyle. The mind-blowing part is that many of the changes we make in our gene expression also pass down to our kids (1).
It may seem scary to think of all the ways that diet and lifestyle can lead to problems in our kids. I hope that your takeaway from this is one of empowerment though. You can use diet and lifestyle to improve most genetic conditions in yourself and in your kids. By creating change in the DNA of your kids, their kids can avoid genetic diseases that have plagued your family.
In 1990, scientists from around the globe began working together to map our genes; an endeavor called the Human Genome Project. Ten years later we had a map of all 23 chromosome pairs and which genetic traits were located where. This amazing feat of research is indirectly leading us to revise everything we thought we knew about genetics and health.
The key finding (for our purposes) is that a tiny fraction of our DNA is genes. The rest was called junk DNA, as it didn’t relate to the genes in a way that was understood at the time. Epigenetics is the field of research that takes a deeper look into that so called “junk DNA”, and what it’s finding is fascinating.
All indications are that our DNA is in flux, adapting to it’s environment through “junk DNA”, constantly learning and documenting (2). Before epigenetics, we believed that genetic changes happened randomly and occasionally. We believed that humans adapted to changing environments by chance; the occasional random mutation would give a person an advantage, which would then pass on to his or her children. We should have known that our genes are smarter than that; they’ve had millennia to learn.
I’ll keep the explanations as simple as possible. Think of your computer or phone and the “brightness” setting. By shifting the slider around, you can control the brightness of the screen, optimizing it for whatever environment you’re in. This is much the same way that your DNA works. There are a few things that are relatively fixed (eye color, etc.), located on your genes, but much of the other DNA is like a setting slider, which will get shifted to match the environment that the genes interpret. This allows your body to adapt to changing circumstances, and allows those shifts to pass on to your unborn children, which is a much better survival strategy than counting on random mutations.
Consider how the body builds bones. To build bones, your body needs calcium, vitamin D, vitamin K, vitamin C, phosphorous and other nutrients, which come mostly from your diet. If the body has plenty of these nutrients, it will likely construct strong, sturdy bones. Think of this as your brightness setting cranked all the way up. If any nutrient is missing or is in lower supply, the body adapts by changing the setting slider and building bones that aren’t ideal (3). The bones will likely be weaker, smaller or not shaped in the best way, but it’s the best that your body can do under the circumstances. It’s been shown that bone loss related to osteoporosis is reflected in the DNA itself, differing in identical twins with different lifestyles (4). Think of this as your brightness being on a lower setting. When conception happens, your genes are passed on with the settings as they are when your body made the egg or sperm cells you provide. If your brightness setting is all the way up at conception, that’s where it starts for your child. If it’s all the way down at conception, that’s where it starts for your child. Before you start feeling scared or guilty, remember that all of these settings are adjustable; by feeding your child well, you’re helping their body and their DNA, which passes on to their kids.
Bones are an easy thing to visualize, but it’s only one of many settings that can be shifted. Your body builds and uses around fifty hormones, which moderate every system in the body; digestion, mood, learning, metabolism, circulation, immune function, speech, socialization, growth, puberty, aging, blood sugar, etc. Every hormone requires specific chemicals to be built, which we’ve evolved to recieve through our diets. Every system that uses hormones requires it’s own chemicals to be function correctly. Epigenetic studies like the ones above imply that if the chemicals aren’t there, the body changes its settings and does damage control. As with the example above, these settings are passed on to your kids through your genes. This has been shown to be true for eyesight (5) and metabolism (6, 7), which is the best explanation I’ve seen for kids developing type 2 diabetes as young as 3 years old. These are an example of a principle: most diseases aren’t a function of permanent genetics, but a result of gene expression (8).
Are you getting a sinking feeling reading about all the things you may have unwittingly passed on to your kids? There’s good news here too! Since so much of what we pass on to our kids is the product of environment, we have the power to improve their gene expression. We have the power to give them bodies and minds that perform beautifully. Even those things that we didn’t do before they were born can be improved. Since there are setting sliders for everything related to our bodies and minds, these sliders can be improved directly through diet and lifestyle. This is especially true for your kids.
While some conditions, especially ones that involve structural disfunction, can’t be “fixed” by diet and lifestyle, most can still be improved. The slider settings that lead to those conditions can be adjusted. By doing so before conception, the condition should be avoidable by the next generation.
What epigenetics implies is that even with 100 generations of ancestors with perfectly healthy lungs, you might develop asthma under the wrong conditions. Epigenetics tells us that this will likely be passed on to your kids. Epigenetics also tells us that even if you have 100 generations of ancestors with asthma, you aren’t doomed to have it yourself, nor are your kids. The same goes for almost every condition you can think of. The key is giving your body the nutrients it needs. The best way to do that is through healthy food.
1- Emilsson, V. (2008). Genetics of gene expression and its effect on disease [Abstract]. Genetics of Gene Expression and Its Effect on Disease, 452, 423-428.
2-Gregory, T. R. (1999). The Modulation of DNA Content: Proximate Causes and Ultimate Consequences [Abstract]. Genome Research,9(4), 317-324.
3-Rosen, C. J. (1996). Osteoporosis::diagnostic and therapeutic principles. Totowa, NJ: Humana Press.
4- Peacock, M. (2002). Genetics of Osteoporosis. Endocrine Reviews,23(3), 303-326. doi:10.1210/er.23.3.303
5- Hale, F. (1937). The relation of maternal vitamin A deficiency to microopthalmia in pigs [Abstract]. Texas State Journal of Medicine, 33, 228-232.
6- Li, C. C., Maloney, C. A., Cropley, J. E., & Suter, C. M. (2010). Epigenetic programming by maternal nutrition: Shaping future generations. Epigenomics, 2(4), 539-549. doi:10.2217/epi.10.33
7- Emilsson, V. (2008). Genetics of gene expression and its effect on disease [Abstract]. Genetics of Gene Expression and Its Effect on Disease,452, 423-428.
8- Shoja, M. M., Tubbs, R. S., Ghaffari, A., Loukas, M., & Agutter, P. S. (2012). Rethinking the Origin of Chronic Diseases. BioScience,62(5), 470-478. doi:10.1525/bio.2012.62.5.8