Alignment of the planetary health diet with pregnancy dietary guidelines: insights from two cohorts

The planetary health diet (PHD) is a mostly plant-based diet that aims to optimise human health while minimising the environmental impact of food production. Limited data exist on whether the PHD fulfils key nutritional requirements during pregnancy. This research aimed to examine the PHD in early pregnancy and how it aligns with daily nutrient intake and European Food Safety Authority (EFSA) dietary guidelines. Pregnant women (n 678) from two Irish cohorts (ROLO and MicrobeMom) were analysed, and PHD index (PHDI) scores were assigned based on data from 3-d food diaries. Women were dichotomised by the median score to create a 'High PHDI' (> 88·99) and a 'Low PHDI' group (≤ 88·99). Differences in nutrient intakes and adherence to dietary guidelines between 'High' and 'Low' PHDI groups were explored. Compared with those with a 'Low' score, those with a 'High' PHDI score reported higher intakes of dietary fibre (g/d) (17·32 (13·39, 21·08) v. 21·74 (18·28, 25·88), P < 0·001), Fe (mg/d) (10·48 (8·48, 12·82) v. 12·06 (9·48, 14·60), P < 0·001), folate (µg dietary folate equivalent per d) (250·73 (193·88, 312·45) v. 279·57 (219·43, 356·81), P < 0·001) and Ca (mg/d) (837·75 (695·36, 1056·72) v. 956·57 (751·84, 1155·03), P < 0·001). A greater proportion of women in the 'High PHDI' group met EFSA recommendations for dietary fibre intake (10·3 % v. 28·9 %, P < 0·001). The PHD may support maternal nutritional adequacy in pregnancy while promoting environmental sustainability. Our findings provide valuable insights that can inform future dietary recommendations for pregnancy, contributing to both maternal health and planetary well-being.