"Food for thought" - On dietary intake, gene expression and physiology

There is a whole array of literature covering dietary habits and how they are or can be linked to gene expression and physiological characteristics; although scientists try their utmost to associate our everyday mundane activities to the well-managed physiological chaos that ensues within us, the fact of the matter is that these associations are very poorly understood and aren’t as simple and straightforward as they may seem when they are reported.

I recently read an article about how the smallest difference in dietary intake can make large differences in gene expression.

A couple of papers published in Cell based on research at the University of Massachusetts Medical School (UMMS) went in-depth about how subtle changes in the diet can trigger changes in metabolism and physiological characteristics. The study was carried out using model organisms, C. Elegans worms and the findings showed that there are regulatory pathways in existence that have strong communication networks that enable them to know what the external conditions are (a.k.a, small changes in food intake). This knowledge can alter the expression of these upstream regulatory factors and therefore lead to solid differences in gene expression. 

Reading this immediately reminded me of an article that I read around this time last year and for obvious reasons was immediately fond of.  It talked about how indulging in a carb-rich diet can ultimately lead to more weight loss, suggesting people have chocolate cakes for breakfast. 

Now, understandably, the two studies actually tackled different questions and attempted to answer them in different ways. Whilst one focused on gene expression and transcription factor regulatory networks which are autonomous within our own bodies (surely we have more important things to worry about than being responsible for switching on and off our own regulatory proteins with our conscious brain), the other study was mainly about experimenting with diets of human participants and had a psychological aspect involved at a much larger context. But surely these studies are interrelated at some level. 

I wondered, if small changes in diet and food intake sets off regulatory networks triggering different sets of genes being expressed, then surely the switch occurs despite the initial dietary change being made for breakfast, dinner or lunch? Why then, would it be okay to have carb-rich foods, even for breakfast?

Ultimately the fact is, as Dr Walhout, team leader of the studies that took place in UMMS put it, “It's very hard to answer questions about the complex interaction between diet, gene expression and physiology”.