Myth Buster: You are what you eat!

By Charlotte Foster BSc (Hons), MSc, RD.

How many times have we heard “You are what you eat”?

To an extent, there is some truth in this – most of us have the ability to make food and lifestyle choices that impact our bodies and health.  However, when we look at the evidence base, we start to see a different message emerge.

There is a hypothesis known as the “thrifty phenotype hypothesis” which has been studied in several populations (1) but has been subject to rigorous questioning and debate (1).

The concept of a thrifty phenotype was devised by Hales and Barker who suggested that if a mother has suboptimal nutrition the foetus will undergo adaptions to metabolic tissues e.g. the liver and pancreas (2).


These adaptions appear to become permanent.  If the baby is born into an environment where food is scarce, having this adaption can be a very advantageous as they will be able to cope better in a nutritionally deprived environment compared with those without this thrifty adaption.

However, if babies carrying this thrifty adaptation are born into an environment where food is abundant (which is the case for many of us in the west), complications can arise as they are most likely to develop diseases associated with over consumption of nutrients e.g. obesity, diabetes and heart disease etc.

There has also been research looking at pregnancy and an excess of nutrients where mothers are overweight/obese which has demonstrated negative effects to the offspring’s health giving them an increased risk of diet-health related diseases (3). However, as obesity has multifactorial causes and therefore difficult to isolate one causative factor.

But all is not lost! What we do know is that partaking in diet modifications and exercise can help with maintaining a healthy weight and reducing the risk of diseases and complications associated with obesity.

So folks, listen up! If you’re of childbearing age and trying for babies your maternal and paternal health matters! It seems that the evidence would say that “you are what your mother ate”, reinforcing the importance of healthy eating throughout conception, pregnancy and beyond!


(1): Wells., J.C.K. (2009) Thrift: a guide to thrifty genes, thrifty phenotypes and thrifty norms. International Journal of Obesity 33; 1331–1338.

(2): Hales., C.N. and Barker., D.J. (2001). The thrifty phenotype hypothesis. British Medical Bulletin 60; 5-20.

(3): Ruager-Martin., R., Hyde M.J. and Modi N. (2010) Maternal obesity and infant outcomes. Early Human Development 86; 715-722.

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