Wednesday, February 9, 2011

Thinking Twice About Your Diet

In most cases, parents will do whatever it takes to secure a happy and healthy life for their children. Commonly, this involves maintaining a reliable income, providing food and shelter, and giving their children unconditional love. But what if doing everything to benefit the health of the child starts way before that child is even conceived? The idea behind this involves a phenomenon called epigenetics. Epigenetics is the means by which an individual’s genotype combines with environmental exposure and resultantly influences that individual’s phenotype and gene expression. A great and incredibly interesting documentary explaining epigenetics can be viewed here. Whether certain genes are “on” or “off” is a matter of a simple methyl group being attached to the gene, which effectively silences that particular gene. Research has proven that methyl groups can be added or removed from genes in response to environmental triggers. Scientists are now beginning to look at how these altered methylation tags are being inherited from generation to generation. In other words, it is becoming evident that experiences and exposures in one person’s lifetime are occasionally reflected in the gene expression of their future children (or grandchildren). This is especially pertinent to diet and nutrition. In the words of researcher Randy Jirtle, “You’re not only what you eat, but potentially what your mother ate and possibly even what your grandparents ate.” This outlook could certainly lead to revolutionary changes in the way we live life.

One study being done on these sort of inheritance patterns has made advances in looking at the effect obese parents have on the health of their children simply by conceiving them. In this study , which was published in Nature, researchers found that fathers who had been exposed to a fatty diet produced daughters with smaller than normal islets. Islets are the groups of beta cells in the pancreas responsible for producing insulin, which regulates glucose levels. Essentially, these daughters were being sentences to extremely high risks of Type II diabetes before their lives had even begun! Researchers were then able to determine that the cause of the small islets was due to altered expression of over 600 genes with an unchanged sequence in the DNA code. One gene in particular, Il13ra2, was found to have only 25% of the levels of methylation of the control gene.

The reliability of these results and whether or not this study can be applied to humans has been highly debated. For instance, it is unclear if the sensitive period of the fatty diet (of the father) is throughout the individual’s entire lifespan or just before the onset of puberty when sperm is forming. Although this is one of the first findings of a nutritional effect being passed on to offspring in mammals, the need for such studies is vital. With a drastic increase in obese men and women conceiving children, we are directly putting the generations to come at a higher risk for diabetes, kidney disease, birth defects and other things which have been linked to obesity. Not to mention, parents leading unhealthy lifestyles are setting poor examples for their children. With more and more research looking into the science behind obesity, it is very likely that we can one day end this epidemic.

Posted by Brianna Lee (2)


  1. Hey Brianna, this is very fascinating documentary. I have had seen this video in my Nutrition class. It was amazing to know that environmental factors such as our diets and lifestyle can change or shut off the expression of our genes. I thought it was interesting to see the effects of environmental factors on the expression of genes in the experiment that was done on rats. I did not know that father’s intake of nutrients like fatty acids can produce smaller islets of daughter. I heard mother has to take very nutrient rich diets to have a healthy child, however, father’s diet can affect child’s health as well was something interesting to know.

    Posted by Arpita Patel

  2. The discussion is certainly warranted; epigenetics is a fascinating field with many applications in both public health and personalized medicine. That said, I wish more could have been mentioned on the specifics of epigenetics in the article: information such as the discovery of mechanisms such as HDACs, HATs and DNAMT and their relation to histone cores may shed more light on the scientific framework behind such a fascinating article.

    Posted by Alexander Simolaris

  3. Arpita, I had also heard a lot about the importance of a mother's diet for the health of her child which is why I found this article really interesting; it doesn't appear that quite as much research has been done on Dad's contribution to the baby's health. And Alexander, I too would have been interesting in learning about the specific mechanisms involved in this research, but I think the article itself was geared to reach the general public, most of which is probably unfamiliar with those concepts.

    Posted by Brianna Lee