Healthy Habits: Maternal Diet and Fetal Health

Sarah Comstock, Ph.D. (Portland State University) is an assistant professor of biology at Corban University. Over the past 15 years she has done extensive research on maternal obesity and fetal development and is well-published in this area. One of her most cited publications, “High-Fat Diet Consumption During Pregnancy and the Early Post-Natal Period Leads to Decreased A Cell Plasticity in the Nonhuman Primate” (Molecular Metabolism, 2012), can be found at http://go.corban.edu/Comstock.

I had a chance to interview her to learn about how maternal diet affects fetal health.

How much does a mother’s diet effect the health of her unborn child?

My research is focused on Developmental Origins of Health and Disease, known as DOHad for those in the scientific community. Many scientists in this field have shown that the environment during fetal life, infancy and childhood, can cause changes in a person that have lasting impact on their health in later life. When you are pregnant, you are “eating for two.” While this may seem like an excuse to indulge, we also must consider that what we eat is what the child is eating. At first, overeating and indulging may seem harmless, but in fact, what a woman puts in her body during pregnancy may impact the health of the child for a lifetime.

As mothers, we have long known that alcohol and tobacco consumption during pregnancy can have a long-lasting, negative impact on the baby, but now research is showing us that our diet and body weight can also lead to major health consequences for our children. This research has demonstrated that a western diet and obesity during pregnancy can lead to long term effects which can pre-dispose the child to develop obesity, diabetes, and cardiovascular disease later in life.

A “western diet” in one that is high in refined sugar, salt and unhealthy fats (mostly fats from processed foods). This type of diet has become prevalent in the United States over the last 30 years and it also coincides with the rise in obesity rates in our nation. In 1985 only about 1 in 10 Americans were obese, whereas now 1 in 3 adults in the US are obese. Obesity during pregnancy can be especially harmful. It increases the risk of miscarriage and, if the pregnancy does go to term, obesity makes it more likely that the mother will develop preeclampsia, infections, gestational diabetes or require a C-section.

And are the effects short-term or long-term?

DOHaD researchers have shown that these effects can be both short and long-term. A child, born to a mother who is obese during pregnancy is at increased risk of being born early or are more likely to have excessive birth weight, respiratory problems or neural tube defects. The long-term effects, as I mentioned earlier, include an increased risk that the child will develop obesity, diabetes, and cardiovascular disease in their adult life (or before). 

Childhood obesity has also been steadily rising and researchers have found that the main factors associated this rise is maternal obesity and western diet consumption. The field is complex and studies in this area are sophisticated. Yet, to simplify things, poor food choices and obesity during pregnancy changes the biology of the baby, so that they crave unhealthy foods and their body does not function as “healthily” as one born to a mother who consumes a healthy diet.  Likewise, a mother who eats poorly during pregnancy consumes these foods as part of a lifestyle and will likely feed her children the same types of foods that she herself eats, perpetuating the cycle of unhealthy food choices. 

To protect her unborn child, how should a pregnant mother eat?

First, I should point out that I am a biologist, not a physician. So, when considering any lifestyle or dietary changes, especially during pregnancy, you should consult a physician. In fact, if you are pregnant, you should be consulting your physician about your diet anyway. A healthy, balanced diet that contains enough vitamins, minerals and macronutrients (fats, protein and carbohydrates) is essential. If you are consuming the “western diet” talk to your physician about how you can transition to eating foods that are better for you and your baby.

If you are obese, meaning you have a body mass index (BMI) before pregnancy of 30 or greater, there may be an increased risk to the baby, but all is not lost! There are some things you can do. One of the major recommendations is to work on pre-pregnancy weight loss. This is not easy, believe me, I know! Talk to a doctor or a certified nutritionist for help. However, if you are pregnant and you are just now finding out about how your weight and diet can affect your child, you may still be able to alleviate some of the risks. Weight loss and restrictive dieting is not recommended during pregnancy. The best thing to do is to avoid those refined sugars and processed foods that are typical of the western diet and start eating a healthy diet under the supervision of your physician. In fact, in my research, we have found that many of the detrimental effects of maternal obesity on the fetus can be reversed if the mother eats a healthy diet, even if the mother doesn’t lose weight.

So, to summarize, what you eat during pregnancy is what your baby eats. Just like you take care to avoid alcohol and tobacco during pregnancy, you should also be wary of the foods you eat. Consult a physician and she or he will help you make the right food choices for your child.