By: Julie C. Shea, MS, RDN, LDN, CPT
During one of your early prenatal appointments, within the general nutrition information most clinics offer, your obstetrician may have encouraged you to stay hydrated – but what does that actually mean? Proper hydration is more than just increasing your intake of plain water and fluids. It’s also about understanding the significance of our body’s increased demand not only for fluids, but also for electrolytes throughout pregnancy and postpartum. There’s no shortage of electrolyte drinks or drink mixes available in today’s sports nutrition market due to the recent buzz around electrolyte supplements. Contrary to the marketing that targets athletes and marathon runners, electrolytes are essential for so many important processes in the body whether you are an athlete or not and especially if you are pregnant and breastfeeding!
What are electrolytes?
At the foundational level, electrolytes are essential minerals that carry an electrical charge and dissolve in water or bodily fluids such as blood, urine, and sweat, as well as cervical and amniotic fluid in pregnancy. These positive or negative electrical charges assist with various chemical reactions throughout the body related to fluid balance and hydration, nerve function, influencing hormone levels and even stabilizing blood sugar. This further supports the idea that adequate intake of electrolytes through the diet should be a priority, especially in pregnancy. The primary electrolytes are calcium, chloride, magnesium, phosphate, potassium, and sodium.
Why are electrolytes important during pregnancy?
It’s no secret that with pregnancy come many significant changes to the body including a substantial increase in blood volume which can start as early as the first trimester! Maternal blood volume increases by roughly 45%, while a 30-50% increase occurs for extracellular fluid volume. With this increase, the American College of Obstetrics and Gynecology (ACOG) recommends 64-96 ounces of water daily during pregnancy. As fluid needs increase, you guessed it, electrolyte needs also increase!
Although more research is needed for conclusive evidence, specific electrolyte minerals have been shown to have a positive impact on maternal health. As previously mentioned, electrolytes are responsible for maintaining fluid balance which can help to mitigate swelling during pregnancy. Electrolytes play an valuable role in muscle function and muscle contractions – pretty important when you think long term to labor and delivery! Let’s not forget about those pesky middle of the night charlie horses which adequate electrolyte balance can help to reduce. Electrolytes may help to lessen or prevent other common pregnancy discomforts such as nausea and fatigue which also happen to be signs of dehydration. Dehydration can lead to vitamin and mineral deficiencies, which during pregnancy can lead to an increased risk of anemia, pregnancy-induced hypertension or pre-eclampsia, fetal growth restriction, and decreased insulin sensitivity.
How do I ensure I’m getting enough?
Luckily, consuming adequate levels of electrolytes during pregnancy is fairly easy to do through a balanced diet, adequate fluid intake and a comprehensive prenatal vitamin. Do your best to prioritize organic, locally sourced, whole food ingredients that have high vitamin and mineral content to maintain electrolyte levels during pregnancy. Despite what the conventional nutrition guidelines suggest, liberally seasoning your food with salt or adding a pinch of salt to your water is an appropriate way to increase your sodium and chloride intake. The key takeaway here is not to consume more highly processed foods, but to consume salt in the context of a whole foods diet. Not only do highly processed foods generally contain low quality salt, they also contain other harmful preservatives, flavors, and additives that are not conducive to a healthy lifestyle. Consider switching to unrefined sea salt or celtic sea salt to benefit from additional trace elements not found in iodized table salt or kosher salt products. Keep in mind salt can also be found in foods such as miso, pickles, olives, and lacto-fermented vegetables like sauerkraut and kimchi which offer additional gut microbiome benefits!
Potassium is an electrolyte that works hand-in-hand with sodium. As sodium intake increases, potassium intake should also increase. Adequate potassium is important for fetal growth, insulin sensitivity, and blood pressure regulation. Focus on potassium rich food sources such as potatoes, citrus, and milk products. Avocados and salmon provide a decent amount of potassium while also providing plenty of healthy fats like omega-3 which are crucial for baby’s health and brain development! Coconut water is another great and refreshing whole food source of potassium – my favorite brands are Harmless Harvest or Coaqua.
Magnesium is responsible for taking part in over 600 enzymatic reactions in the body, yet magnesium deficiency in pregnancy is quite common. It may prove challenging to consume adequate magnesium from food sources alone, however magnesium rich foods include pumpkin seeds, brazil nuts, chia seeds, tahini, leafy greens, and certain types of seafood like cod, halibut and salmon. In addition to regular consumption of these foods, be sure you’re taking a comprehensive prenatal vitamin to supplement your intake.
Although calcium needs do not increase during pregnancy, calcium absorption doubles in pregnancy meaning you will take in more of the calcium from the foods you are eating. Adequate calcium intake can be met through consumption of cheese and milk products, sesame seeds, chia seeds, tahini and fish canned with the bones.
What about electrolyte supplements?
As mentioned at the beginning of this article, there are plenty of electrolyte supplements available in today’s market. Unfortunately, few provide the appropriate balance of electrolytes without unnecessary added sugar, preservatives, and artificial colors and flavors – I’m looking at you Gatorade! Processed and added sugars have been shown to increase cravings and insulin resistance (a natural occurrence in pregnancy already) and are a sneaky ingredient in many processed items on the shelves, including electrolyte supplements. Artificial sweeteners aren’t any better as they have been shown to alter the gut microbiome and may cause laxative effects. As always, consult with your doctor before starting any new supplements, but the following are registered dietitian approved: Just Ingredients Electrolytes, Nectar Hydration Packets, Seeking Health Optimal Electrolyte and Needed Hydration Support. Each of these brands use real food ingredients, no artificial flavors or colors, and offer an ideal balance of sodium, potassium, magnesium and chloride. If you’re not in the market for another supplement to worry about taking, you can have fun at home creating your very own electrolyte drink with whole food ingredients you probably already have on hand! Visit the BumptUp instagram for an easy watermelon electrolyte refresher recipe, perfect for any trimester or postpartum!
In summary, consuming adequate electrolytes during pregnancy is important for you and your baby’s health. Within the research that is available, many of the electrolyte minerals have been shown to have beneficial effects on maternal and fetal health outcomes. Growing a baby is no easy task and your body is working overtime to nurture both you and your little one. Make sure you remember to nourish it well so you can feel your best during pregnancy, labor, delivery and beyond! Consider your daily sources of electrolyte intake and utilize the BumptUp app’s ‘Ask an Expert’ feature to speak with our dietitian for more tailored guidance and suggestions – happy hydrating!
- MedlinePlus [Internet]. Bethesda (MD): National Library of Medicine (US); [updated 2024 May 16]. Fluid and Electrolyte Balance; [updated 2024 May 16; cited 2024 Jul 11]. Available from: https://medlineplus.gov/fluidandelectrolytebalance.html
- Grzeszczak, Konrad et al. “Calcium, Potassium, Sodium, and Magnesium Concentrations in the Placenta, Umbilical Cord, and Fetal Membrane from Women with Multiple Pregnancies.” Life (Basel, Switzerland) vol. 13,1 153. 5 Jan. 2023, doi:10.3390/life13010153
- Soma-Pillay, Priya et al. “Physiological changes in pregnancy.” Cardiovascular journal of Africa vol. 27,2 (2016): 89-94. doi:10.5830/CVJA-2016-021
- Khayat, Samira et al. “Minerals in Pregnancy and Lactation: A Review Article.” Journal of clinical and diagnostic research : JCDR vol. 11,9 (2017): QE01-QE05. doi:10.7860/JCDR/2017/28485.10626
- How much water should I drink during pregnancy? ACOG. Reviewed October 2020. https://www.acog.org/womens-health/experts-and-stories/ask-acog/how-much-water-should-i-drink-during-pregnancy
- Zhang, Na et al. “Associations between hydration state and pregnancy complications, maternal-infant outcomes: protocol of a prospective observational cohort study.” BMC pregnancy and childbirth vol. 20,1 82. 7 Feb. 2020, doi:10.1186/s12884-020-2765-x
- Nichols, Lily. “Electrolytes & Pregnancy: Why These Minerals are Crucial and How to Get Enough.” Cited 2024 Jul 11. Available from: https://lilynicholsrdn.com/electrolytes-pregnancy/
- Ruiz-Ojeda, Francisco Javier et al. “Effects of Sweeteners on the Gut Microbiota: A Review of Experimental Studies and Clinical Trials.” Advances in nutrition (Bethesda, Md.) vol. 10,suppl_1 (2019): S31-S48. doi:10.1093/advances/nmy037
