New scientific evidence shows that a woman's diet when pregnant can actually alter the structure of her baby's genes. A study, conducted by the American Diabetes Association, concludes: "Our findings suggest a substantial component of metabolic disease risk has a prenatal developmental basis." What this means in plain English is that, contrary to previous beliefs about the "fixed" nature of DNA, our diet may effect the development of our offspring in fundamental ways.

Epigenetics is the study of how environmental factors, including diet, can affect our DNA. While it has previously been believed that the growing problem of childhood obesity was linked only with the child's diet after birth, this new study reveals that the mother's diet when she is pregnant may actually create epigenetic changes in her offspring that make the child more predisposed towards obesity.

What the Study Found

Researchers in the UK, New Zealand and Singapore studied the epigenetic changes that occurred in 300 babies using tissue from their umbilical cords to measure their rates of change. Then they looked for a correlation between the rate of epigenetic change and the weights of the children when they reached the ages of six to nine.

According to researcher Dr. Peter Gluckman from Auckland University's Liggins Institute, as quoted in the Sydney Morning Herald,  the "correlation was very strong." He went on to say: "We didn't believe it at first, so we replicated it again and again." Dr. Gluckman and his team speculate that the mother's diet during the first trimester (3 months) of pregnancy could be responsible for this. Their working theory is that a developing embryo, when fed a low carbohydrate diet, may alter its metabolism, allowing it to store more fat to use to fuel its body when faced with a perceived food scarcity later in life.

The Significance of the Findings

Studies such as this are changing the way scientists are thinking about DNA and the effects of diet not only on our own bodies, but on future generations. Ever since Darwin proposed his Theory of Evolution, the predominating theory has been that evolution is a very slow process and that current environmental factors did little if anything to change our genetic make-up. This study and others like it in the field of epigenetics are showing that the changes we make in our lifestyles, for better or for worse, can have a profound impact on our genetic make-up, even within a single generation.

In his recent Time article, 'Why Your DNA Isn't Your Destiny', author John Cloud writes, "environmental factors like diet, stress and prenatal nutrition can make an imprint on genes that is passed from one generation to the next." Epigenetics seems to be proving the age old adage, "You are what you eat" is true not only after birth, but even in the embryonic stages of development when the foetus is entirely dependent on its mother's dietary choices.