Developmental Biology - Pregnancy Diet|
Mediterranean Diet Improves Pregnancy Health
Nuts and extra virgin olive oil are key to improving health of moms with gestational diabetes...
In a new clinical trial, women who followed a Mediterranean-style diet during pregnancy, including a daily portion of tree nuts (half being walnuts) and extra virgin olive oil, had a 35 percent lower risk of gestational diabetes and on average, gained 2.75 pounds less, as compared to women who received standard prenatal care.
A Mediterranean-style diet had been shown to reduce the risk of heart attack, stroke, and cardiovascular death in adults, following the 2013 landmark PREDIMED study re-released in 2018. Walnuts are a traditional food in the Mediterranean diet with their omega-3 ALA content.
Despite extensive research on the Mediterranean diet, its potential to improve mother and baby outcomes has not been widely evaluated, making this study particularly valuable. Conducted by researchers at Queen Mary University of London and the University of Warwick, this newest study included 1,252 multi-ethnic inner-city pregnant women with metabolic risk factors, including obesity and chronic hypertension.
In addition to receiving folic acid and vitamin D supplementation, pregnant women were randomly assigned to either a Mediterranean-style diet or a control group that received dietary advice as per United Kingdom national recommendations for prenatal care and weight management in pregnancy. Study results are published in the journal PLOS/Medicine.
Those who followed the Mediterranean diet consumed a daily portion of nuts (30g/day; 15g walnuts, 7.5g almonds, 7.5g hazelnuts) and used extra virgin olive oil (0.5L/week) as their main source of cooking fat.
In addition, the diet emphasized fruit, vegetables, non-refined grains and legumes; moderate to high consumption of fish; small to moderate intake of poultry and dairy products; low intake of red meat and processed meat; avoidance of sugary drinks, fast food, and food rich in animal-based fat.
Women received dietary advice at 18, 20, and 28 weeks' gestation to help improve compliance and make sure the diet was made culturally sensitive.
Dietary compliance was measured using self-reported feedback from the women participating, so it's important to point out there could have been human error in their reporting. But, researchers also assessed the effect of the diet on other pregnancy complications such as high blood pressure, preeclampsia, stillbirth, small for gestational age fetal development, or any admission to a neonatal care unit — and did not find any significant associations.
One in four mothers enter pregnancy with pre-existing obesity, chronic hypertension or raised lipid levels, which can lead to pregnancy complications such as long-term risk for diabetes or cardiovascular complications for mothers and their children. So study findings provided additional support for women following a Mediterranean-style diet linked to additional health benefits such as improved brain function.
The discussion surrounding the retraction and republication of the landmark PREDIMED research study is an important reminder that solid science is not based on any single study, but the result of sustained and critically evaluated research by multiple investigators through many studies, over many years.
Pregnant women with metabolic risk factors are at high risk of complications. We aimed to assess whether a Mediterranean-style diet reduces adverse pregnancy outcomes in high-risk women.
Methods and Findings
We conducted a multicentre randomised trial in 5 maternity units (4 in London and 1 in Birmingham) between 12 September 2014 and 29 February 2016. We randomised inner-city pregnant women with metabolic risk factors (obesity, chronic hypertension, or hypertriglyceridaemia) to a Mediterranean-style diet with high intake of nuts, extra virgin olive oil, fruits, vegetables, nonrefined grains, and legumes; moderate to high consumption of fish; low to moderate intake of poultry and dairy products; low intake of red and processed meat; and avoidance of sugary drinks, fast food, and food rich in animal fat versus usual care. Participants received individualised dietary advice at 18, 20, and 28 weeks’ gestation. The primary endpoints were composite maternal (gestational diabetes or preeclampsia) and composite offspring (stillbirth, small for gestational age, or admission to neonatal care unit) outcomes prioritised by a Delphi survey. We used an intention-to-treat (ITT) analysis with multivariable models and identified the stratification variables and prognostic factors a priori.
We screened 7,950 and randomised 1,252 women. Baseline data were available for 593 women in the intervention (93.3% follow-up, 553/593) and 612 in the control (95.6% follow-up, 585/612) groups. Over a quarter of randomised women were primigravida (330/1,205; 27%), 60% (729/1,205) were of Black or Asian ethnicity, and 69% (836/1,205) were obese. Women in the intervention arm consumed more nuts (70.1% versus 22.9%; adjusted odds ratio [aOR] 6.8, 95% confidence interval [CI] 4.3–10.6, p <= 0.001) and extra virgin olive oil (93.2% versus 49.0%; aOR 32.2, 95% CI 16.0–64.6, p <= 0.001) than controls; increased their intake of fish (p < 0.001), white meat (p < 0.001), and pulses (p = 0.05); and reduced their intake of red meat (p < 0.001), butter, margarine, and cream (p < 0.001). There was no significant reduction in the composite maternal (22.8% versus 28.6%; aOR 0.76, 95% CI 0.56–1.03, p = 0.08) or composite offspring (17.3% versus 20.9%; aOR 0.79, 95% CI 0.58–1.08, p = 0.14) outcomes. There was an apparent reduction in the odds of gestational diabetes by 35% (aOR 0.65, 95% CI 0.47–0.91, p = 0.01) but not in other individual components of the composite outcomes. Mothers gained less gestational weight (mean 6.8 versus 8.3 kg; adjusted difference -1.2 Kg, 95% CI -2.2 to -0.2, p = 0.03) with intervention versus control. There was no difference in any of the other maternal and offspring complications between both groups. When we pooled findings from the Effect of Simple, Targeted Diet in Pregnant Women With Metabolic Risk Factors on Pregnancy Outcomes (ESTEEM) trial with similar trials using random effects meta-analysis, we observed a significant reduction in gestational diabetes (odds ratio [OR] 0.67, 95% CI 0.53–0.84, 12 = 0%), with no heterogeneity (2 trials, 2,397 women). The study’s limitations include the use of participant reported tools for adherence to the intervention instead of objective biomarkers.
A simple, individualised, Mediterranean-style diet in pregnancy did not reduce the overall risk of adverse maternal and offspring complications but has the potential to reduce gestational weight gain and the risk of gestational diabetes.
Bassel H. Al Wattar, Julie Dodds, Anna Placzek, Lee Beresford, Eleni Spyreli, Amanda Moore, Francisco J. Gonzalez Carreras, Frances Austin, Nilaani Murugesu, Tessa J. Roseboom, Maira Bes-Rastrollo, Graham A. Hitman, Richard Hooper, Khalid S. Khan and Shakila Thangaratinam.
This study was supported by the University of California, San Francisco, California Preterm Birth Initiative, funded by Marc and Lynne Benioff.
No potential conflict of interest was reported by the authors.
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Aug 16 2019 Fetal Timeline Maternal Timeline News
In a new clinical trial, women who followed a Mediterranean-style diet during pregnancy, including a daily portion of nuts (half being walnuts) and extra virgin olive oil, had a 35 percent lower risk of gestational diabetes and on average, gained 2.75 pounds less, as compared to women who received standard prenatal care. CREDIT ukrnut.com