Methylation and Exercise
Exercise is linked to the reduction of various diseases, including cancer. But how, exactly, does exercise reduce one’s risk of cancer you may ask? A recent study showed that chronic regular exercise can actually change methylation patterns in your DNA, keeping the watchdog-like tumor suppressor genes on, through methylation.
Methylation and Epigenetics: What You Need to Know
The ability to turn genes on and off, synthesize hormones, and make feel-good neurotransmitters is dependent upon a biological process called methylation. Simply put, methylation is the addition or removal of a methyl group (chemically one carbon atom covalently linked to three hydrogen atoms).
Since our genes are relatively unmodifiable, we really depend on methylation in order to adapt to our environment—to turn genes on or off when needed. The addition of a methyl group to the protective coating of a gene (a histone) silences the gene’s expression. The subtraction of a methyl group and the addition of an acetyl group to the histone expose the gene (region of DNA) and allow it to be read, so proteins like hormones and neurotransmitters can be made.
This, in essence, is epigenetics: the environmental control of gene expression. The foods we eat (or don’t eat), the toxins we’re exposed to, our sleep patterns, and our exercise all influence epigenetics through methylation. For example, various cancers are often linked with increased methylation of protective tumor suppressor genes. Since methylation silences genes, this is problematic because tumor suppressor genes are protective.
Exercise Offers Health Benefits by Altering DNA Methylation Patterns
A scientific review reported that exercise changes methylation patterns, offering health benefits with regard to cancer prevention. Here is a summary of key findings:
Elite Athletes and MTHFR Alleles
The study reported that elite athletes were more likely to be heterozygous for variants in MTHFR, MTR, and MTRR compared to non-elite athletes. 1298A>C was much more common, and it may be that the C allele offers some performance benefits.
High-Intensity Interval Training Changes Mitochondrial DNA Methylation
A short burst of high-intensity exercise changed DNA methylation patterns in many key metabolic enzyme systems related to fat burning in the mitochondria, including PGC-1 alpha, PDK4, and PPAR gamma. After exercise, these genes were hypomethylated, which means they were turned on.
Chronic Moderate Exercise Training Activates Tumor Suppressor Genes
This study reported that six months of high-intensity interval walking increased methylation of DNA regions coding for inflammatory signaling. The control group did not exhibit such changes in their DNA methylation. Thus, it was concluded that exercise can effectively reduce the expression of proinflammatory cytokines.
Exercise Changes Genes Associated with Diabetes Risk
A recent genome-wide methylation study reported that chronic regular exercise changed the methylation patterns of 134 genes in muscle tissue; reducing the methylation of these genes and thus activating them. Key genes involved in the cellular energy production were hypomethylated (a good thing).
The group also looked at exercise-related methylation patterns in fat tissue and reported that of the 7,663 genes in fat tissue measured, 92 percent of them showed increased methylation (suppression of gene signaling—again a good thing).
Conclusion: Practice HIIT (High-Intensity Interval Training)
Get out there and perform some high-intensity interval training (HIIT)! Remember that exercise quality, not quantity, has a greater effect on body weight. Researchers have found that the combination of aerobic and resistance exercise leads to greater fat loss and larger increases in lean muscle mass than simply aerobic exercise alone. HIIT is surfacing as superior to steady-state aerobic training even though it has a lower impact on calorie burn in comparison to traditional aerobic exercise.
HIIT not only helps keep fat off the abdomen and move blood around, but based on this recent review, HIIT training also leads to beneficial changes in the way our genes are read. This helps reduce your risk of cancers and metabolic diseases.
Voisin, S., Eynon, N., Yan, X., & Bishop, D. J. (2014). Exercise training and DNA methylation in humans. Acta Physiologica, n/a–n/a. doi:10.1111/apha.12414