A growing body of research is shedding light on the link between diet and children’s mental health. Poor diet is thought to increase the risk of “internalizing” disorders, such as depression and anxiety, as well as “externalizing” disorders like conduct disorder, oppositional defiant disorder, and attention deficit/hyperactivity disorder. Both a woman’s prenatal diet and a child’s diet in the first few years of life, as well as later on, can impact the child’s mental health as early as between 18 months and 5 years of age, as well as later on. This is thought to be due to the fact that the prenatal period and the first few years of life are critical times for a child’s brain development.
The most recent study looked at the dietary habits of over 23,000 pregnant Norwegian women and their children. Pregnant women were given diaries to record their food and beverage intake. In order to rule out the potential effects of these factors, the team also assessed the women’s socioeconomic status, level of educational attainment, whether or not they smoked, and whether or not they were depressed both during the first 4-5 months of pregnancy and when their children were 1.5 and 3 years old. The children’s mood and behavior were evaluated via the Child Behavior Checklist at 1.5, 3, and 5 years.
The researchers noted that two major dietary patterns emerged for the mothers, namely, a “healthy” pattern characterized by a high intake of vegetables, fruit, high-fiber cereals, and vegetable oils, and an “unhealthy” pattern characterized by high intake of processed meat products, refined cereals, sweetened drinks, and salty snacks.
The women also filled out questionnaires about their child’s diet when they were 18 months and 3 years old. Again, two patterns of eating emerged: The “unhealthy” one described a pattern of eating characterized by consumption of chips, buns, cakes, waffles, chocolate, cookies, sweets, soda, ice cream, popsicles, bread with jam or honey, pizza, and soda with artificial sweeteners. The “healthy” one was characterized by consumption of white fish, oily fish, boiled vegetables, raw vegetables, fruit, bread with fish products, eggs, bread with meat, Norwegian brown cheese, and fish products.
The team found that higher intake of unhealthy foods in pregnant women predicted more externalizing problems in their children – independently of the contribution made by the child’s diet post-natally. Furthermore, children’s poor diet, as defined by increased intake of unhealthy foods and decreased intake of healthy foods, predicted both internalizing and externalizing problems in young children. These results were independent of the mental health or socioeconomic status of the mothers.
Although these findings are preliminary, there are biological explanations for why maternal and early childhood diets would influence children’s mental health. Among them are that deficiencies of certain nutrients may result in irreversible changes to the developing brain, including to the neurotransmitter systems (neurotransmitters are chemicals that regulate mood, among other aspects of mental health). In other research, rodents given a typical “western” high-fat, high-sugar diet were more likely to have offspring who showed increased sympathetic nervous system activity and hyperactivity. Mice who were deficient in other nutrients, such as omega-3 fatty acids, have had offspring who exhibited anxiety. Other research has established that maternal famine is a risk factor for major depression in offspring.
The take home message from this research is that diet is one factor over which most people have some degree of control, food preferences, morning sickness, and allergies aside. Although pregnancy can present challenges with regard to food aversions, cravings, and for some, fears of gaining weight, aiming for a healthy diet pre and post natally is an essential part of providing good care for one’s child. The good news is that even in families were mood and other issues are prevalent, consuming a healthy diet may buffer those effects.
Jacka FN, Ystrom, E., Brantsaeter, A.L., Karevold, E., Roth, C., & Haugen, M., et al. (2013). Maternal and early postnatal nutrition and mental health of offspring by age 5 years: a prospective cohort study. Journal Of The American Academy Of Child And Adolescent Psychiatry,52 (10), 1038-47.
The American College of Obstetricians and Gynecologists, “Nutrition During Pregnancy.” http://www.acog.org/~/media/For%20Patients/faq001.pdf?dmc=1&ts=20131015T1738251321
The Academy of Nutrition and Dietetics, “Children’s Health.” http://www.eatright.org/Public/landing.aspx?TaxID=6442451994