A new US study has discovered that following a Mediterranean diet whilst pregnant can reduce the risk of preeclampsia, potentially illustrating how dietary interventions can help to prevent the condition.
The research, published in the Journal of the American Heart Association, found that eating a Mediterranean diet was associated with a reduced risk of developing preeclampsia, with the most significant risk reduction demonstrated among Black women.
Previous studies signified that a Mediterranean diet, which includes mainly vegetables, fruits, legumes, nuts, olive oil, whole grains, and fish, can lower the risk of heart disease; this novel study suggests the diet may have beneficial effects on a range of conditions.
What is preeclampsia?
Preeclampsia is a condition that occurs during pregnancy, with symptoms including high blood pressure and liver or kidney damage. Preeclampsia is a major cause of pregnancy complications and death for the mother and their unborn child.
Moreover, preeclampsia more than doubles a woman’s risk of developing heart disease such as high blood pressure, heart attack, stroke, or heart failure later in life. Additionally, women with preeclampsia have an elevated risk of giving birth before week 37 of gestation – preterm delivery – or babies with low birth weight. Children born to mothers with preeclampsia are also more likely to develop high blood pressure or heart disease.
Studies suggest that Black women are at a higher risk of preeclampsia, and treatments for high-risk women are limited. To combat this, the team examined whether dietary changes can mitigate the condition, analysing the effects of a Mediterranean diet in a large group of ethnically and racially diverse women who have a high preeclampsia risk.
Anum S. Minhas, MD, M.H.S., chief cardiology fellow and a cardio-obstetrics and advanced imaging fellow at Johns Hopkins University, commented: “The US has the highest maternal mortality rate among developed countries, and preeclampsia contributes to it. Given these health hazards to both mothers and their children, it is important to identify modifiable factors to prevent the development of preeclampsia, especially among Black women who are at the highest risk of this serious pregnancy complication.”
Can following a Mediterranean diet reduce preeclampsia risk?
The investigation included data from over 8,500 women who were enrolled between 1998 and 2016 in the Boston Birth Cohort. The median age of the participants was 25, and they were recruited from Boston Medical Center, which usually serves a mainly urban, low-income, underrepresented racial and ethnic population.
Of the participants, 47% were Black women, 28% were Hispanic women, and the remaining were either White or ‘other race’, according to self-reported data on a postpartum questionnaire. Subsequently, the team designed a Mediterranean diet score based on the individuals’ responses to food frequency interviews and surveys performed within three days of giving birth.
The analysis revealed that 10% of the participants developed preeclampsia, and women who had any diabetes or obesity before pregnancy were twice as likely to develop preeclampsia than women without these conditions. The study also found that women who followed the Mediterranean diet were more than 20% less likely to develop preeclampsia. Furthermore, Black women with the lowest Mediterranean diet scores had the highest risk for preeclampsia (&*%) compared to all other non-Black women who followed the diet more closely.
Minhas concluded: “We were surprised that women who more frequently ate foods in the Mediterranean-style diet were significantly less likely to develop preeclampsia, with Black women experiencing the greatest reduction in risk. This is remarkable because there are very few interventions during pregnancy that are found to produce any meaningful benefit, and medical treatments during pregnancy must be approached cautiously to ensure the benefits outweigh the potential risks to the mother and the unborn child.
“Women should be encouraged to follow a healthy lifestyle, including a nutritious diet and regular exercise, at all stages in life. Eating healthy foods regularly, including vegetables, fruits and legumes, is especially important for women during pregnancy. Their health during pregnancy affects their future cardiovascular health and also impacts their baby’s health.”
The researchers noted some limitations of their study, such as the food frequency interviews only being performed once after the pregnancy and relying on self-reported information about which foods were consumed and in what quantity.