Your growing baby's short-term and long-term health critically depend on your nutritional status both before and during pregnancy. A healthy pregnancy diet should reflect a combination of macronutrients -- fats, proteins, and carbohydrates --- with a focus on several important micronutrients including -- essential fatty acids, and folate. Otherwise, without making conscious, informed choices about your nutrition your baby is susceptible to a variety of diseases and complications including low birth rate, diabetes, heart disease and hypertension, and even cancer.
Heart Disease and Hypertension
A popular epidemiological study from 1945 revealed alarming data showing babies who were born during famine where their mothers were only eating 400 to 800 total calories per day later developed heart disease and hypertension. It is theorized that after undergoing malnutrition during gestation babies undergo fetal adaptation where they essentially enter a catch-up period after birth in order to adapt to a diet that the body is designed to consume. In other words, a lack of nutrition in utero can lead to the overconsumption of calories after birth and ultimately result in cardiovascular disease, hypertension, and diabetes during adulthood. (Resource 1) Because energy is the chief component contributing to fetal weight gain, the American Dietetic Association recommends a general daily caloric intake of 2,200 to 2,900 per day after the first trimester of pregnancy. (Resource 2)
Neural Tube Defects and Low IQ
Folic acid and essential fatty acids are critical during pregnancy in order to prevent neural tube defects and poor brain development, respectively.