May is Preeclampsia Awareness Month, and May 22nd marks World Preeclampsia Day.¹ The Preeclampsia Foundation’s theme for 2023 is “Move Preeclampsia Research Forward.” Preeclampsia is a condition during pregnancy that can lead to hypertension and kidney damage, but knowledge on why this happens in some pregnancies remains sparse.
Your patients who are pregnant or are looking to conceive may want to know what research has shown in terms of potential risk factors for developing preeclampsia. Left untreated, the condition can cause significant complications for mother and child alike, including early delivery and mortality.²
One modifiable risk factor your patients may be curious about is diet. As preeclampsia involves an elevation in blood pressure, could a healthy diet play a role in reducing risk? What do we know about a potential link?
Diet and Preeclampsia Risk Factors
While diet is not strictly considered to be a risk factor in preeclampsia development, a number of other risk factors can be exacerbated by an unhealthy diet. Obesity is seen as a moderate preeclampsia risk factor, and there are several conditions that carry even greater risk. These include:²
- Kidney disease
- Chronic high blood pressure
Though these conditions do not guarantee the development of preeclampsia, elevated blood pressure or uncontrolled diabetes prior to pregnancy may significantly increase a patient’s risk.
A 2022 study in BMJ Nutrition, Prevention & Health examined data on preeclampsia and diet in pregnant women and found certain vitamins and nutrients may help mitigate risk.³ The researchers suggested that a high intake of dietary fiber could be protective against preeclampsia, as it can help reduce blood pressure, cholesterol, and inflammation. They also noted that probiotic consumption could have protective effects in late pregnancy, but acknowledged that further research is needed.
Calcium is another nutrient the investigators found may protect against preeclampsia risk. While the researchers found inconsistent evidence as to whether vitamin D is definitively linked to reduced preeclampsia risk, it is still recommended as part of a healthy diet for pregnancy.
The researchers also uncovered data that suggested selenium intake was inversely correlated with preeclampsia risk; patients with a lower concentration of selenium were found to be at greater risk for developing the condition. Pregnant women with lower levels of selenium may benefit from supplementation or an increased intake of foods that contain selenium, such as seafood.
Diets high in certain foods can lead to an increased risk in preeclampsia, in large part due to their effects on blood pressure, cholesterol, inflammation, and diabetes. Diets rich in salt, sugar, and fat were associated with increased preeclampsia risk, as were dietary patterns the researchers defined as “western.” These dietary patterns involved greater consumption of red and processed meats, fried potatoes, white bread, and pickles compared to other diets.
What Diets May Help Preeclampsia Prevention?
The researchers also presented the Mediterranean diet as a healthy option for women who are pregnant or trying to conceive, and other studies have found similar benefits.
Research published in the Journal of the American Heart Association in April 2022 examined how intake of the Mediterranean diet affected preeclampsia risk and found significant benefits.⁴ The Mediterranean diet is defined as a diet high in fruits, vegetables, legumes, and healthy fats that avoids foods high in unhealthy fats, salt, and sugar. Of the 8,507 women included in this study, 848 developed preeclampsia between 1999 and 2014. A lower Mediterranean-style diet score correlated with a higher risk of preeclampsia, as a larger percentage of those in the lowest tertile of scores had preeclampsia than those in the middle and high tertiles.
This study also found the Mediterranean diet to have protective features against preeclampsia in Black women, a significant finding as Black women have a heightened risk of developing preeclampsia due in large part to the disparity in health care resources available to them.
Another diet that has shown promise in reducing preeclampsia risk is the New Nordic Diet.³ This diet is characterized by eating at least 24 meals in a week, consuming cabbage at least twice a week, and drinking at least six times as much water as sugary beverages. Adherence to this diet is associated with a lower risk for preeclampsia.
Generally, the diets recommended for lowering preeclampsia risk are the same as those recommended for anyone trying to eat healthier and lose weight or lower their blood pressure. Avoiding foods high in salt, sugar, and fat and replacing them with fruits, vegetables, and fiber is a good way to lower cholesterol, reduce hypertension, and control diabetes. It is important for patients to do what they can to reduce their risk of preeclampsia; pregnancy can bring symptoms that may make preeclampsia symptoms harder to distinguish.
It’s important to remind your patients that all of these diets may reduce risk, but will not eliminate the possibility entirely. While high blood pressure and diabetes may be risk factors indicative of future preeclampsia, they do not guarantee it, just as not having them prior to pregnancy cannot rule out the possibility of preeclampsia during or after pregnancy.
What Else Can Patients Do to Lessen Preeclampsia Risk?
While preeclampsia risk cannot be 100% mitigated, there are other things that can be done to try and lessen it. One way could be taking low-dose aspirin. In 2021, the US Preventive Services Task Force released a statement in an update to their 2014 recommendation that daily low-dose aspirin intake has a number of benefits during pregnancy.⁵ They recommend 81 mg/d, starting after 12 weeks of gestation to help prevent preeclampsia.
Perhaps the most important thing patients can do to reduce their risk of preeclampsia is to keep up with their regular medical appointments, where they can stay on top of their health and find possible irregularities as early as possible. Preeclampsia can’t always be avoided, but the earlier it is detected the earlier health care professionals can monitor the condition and prescribe appropriate medications. These treatments can include antihypertensive drugs, corticosteroids, and antiseizure medications.⁶
1. May is Preeclampsia Awareness Month. Preeclampsia Foundation. https://www.preeclampsia.org/AwarenessMonth. Updated April 29, 2023. Accessed May 2, 2023.
2. Preeclampsia – Symptoms and causes. Mayo Clinic. https://www.mayoclinic.org/diseases-conditions/preeclampsia/symptoms-causes/syc-20355745. Updated April 15, 2022. Accessed May 3, 2023.
3. Perry A, Stephanou A, Rayman MP. Dietary factors that affect the risk of pre-eclampsia. BMJ Nutr Prev Health. 2022 Jun 6;5(1):118-133. doi: 10.1136/bmjnph-2021-000399. PMID: 35814725; PMCID: PMC9237898.
4. Minhas AS, Hong X, Wang G, et al. Mediterranean‐style diet and risk of preeclampsia by race in the Boston Birth Cohort. J Am Heart Assoc. 2022;11(9). doi:10.1161/jaha.121.022589
5. US Preventive Services Task Force. Aspirin Use to Prevent Preeclampsia and Related Morbidity and Mortality: US Preventive Services Task Force Recommendation Statement. JAMA. 2021;326(12):1186–1191. doi:10.1001/jama.2021.14781
6. Preeclampsia – Diagnosis & treatment. Mayo Clinic. https://www.mayoclinic.org/diseases-conditions/preeclampsia/diagnosis-treatment/drc-20355751. Updated April 15, 2022. Accessed May 3, 2023.