Committed to delivering pharmacist-focused education, Pharmacy Magazine recently hosted a webinar in partnership with Inova navigating micronutrient interactions in pregnancy. The following article is based on the presentation.
With over 25 years of experience and a deep passion for the first 1000 days, speaker Kath Megaw (clinical paediatric dietitian) drew on current evidence to explore how micronutrients interact, influence one another's absorption, and ultimately shape maternal and foetal outcomes.
Megaw framed pregnancy nutrition as an interacting biological system. “Prenatal supplements may contain up to 20 different nutrients, but the body does not process those nutrients as 20 separate ingredients,” she explained. Micronutrient adequacy, she stressed, is the combined result of availability, interaction, absorption, utilisation and timing, not simply intake.
Three interaction patterns were discussed: synergy, where one nutrient enhances another's function; antagonism, where one reduces another's absorption or effect; and conditional interaction, where the outcome depends on dose, timing, form and clinical context. “An interaction does not automatically mean nutrients must never be taken together, but it does mean that formulation, dose, timing and clinical context always needs to be considered,” Megaw said.
Food matrix emerged as a central theme. Megaw stressed that nutrient content on a label is only the starting point, and that “nutrient content is not the same as nutrient delivery”. Vitamin C-rich foods enhance non-haem iron absorption, while tea, coffee, and phytates inhibit it. Preparation methods such as soaking, sprouting, and fermenting improve mineral delivery from plant foods, and fat-soluble vitamins require dietary fat for optimal uptake.
On mineral competition, Megaw discussed the shared-traffic problem of iron, zinc and copper, warning that high-dose single minerals may correct one biomarker while altering another's status. She cited a Tanzanian trial where prenatal zinc and vitamin A reduced some expected benefits of iron supplementation, demonstrating that combined formulations do not always produce simple additive effects.
Megaw also explored the calcium-magnesium-vitamin D triad, the iodine-selenium thyroid partnership, and the role of folate, B12, and B6 in the methylation cycle. She highlighted that environmental exposures, including toxic metals, form part of the micronutrient picture and should be considered alongside nutritional assessment.
The webinar concluded with a precision framework: assess diet, supplements and exposure risks; identify deficiencies, duplications and poor timing; design a food-first plan with targeted supplementation; and review labs, symptoms and adherence. “Precision nutrition in pregnancy is not about adding the greatest number of nutrients. It is about creating the right nutrient relationship in the right women at the right time,” Megaw said.
An interactive Q&A session followed, covering the bioavailability of commercially available micronutrients, water-soluble vitamin safety, folate in oral contraceptives, pregnancy cravings and microplastic exposure.
To watch the replay, click here.
To download presentation, click here.
