The short version: making milk takes a lot of water and electrolytes are an important part of that process. More than most of us realize, and more than most of us are replacing.
Here's what's actually going on in your body, why plain water sometimes doesn't seem to do the trick, and what nursing moms have found genuinely helps.
Breastfeeding is a hydration event
Breastmilk is about 87% water [1]. Most moms produce somewhere between 25 and 32 ounces of milk a day once supply is established [2], which means your body is moving roughly a quart of water out of you, every day, on top of everything else it's already doing.
The general recommendation for total water intake jumps from about 11 cups a day for women to around 16 cups a day for nursing moms [3]. That's a 45% increase — and it's a baseline, not a goal. If you're in a hot climate, exercising, or running on three hours of sleep and a lot of postpartum sweating, your needs are higher.
Most nursing moms aren't hitting that number. It's not for lack of trying — between feeds, diaper changes, and barely remembering to eat lunch, hydration is one of the first things to slip through the cracks.
Why you might feel "off" even when you're drinking water
Here's the part that surprises a lot of moms: you can drink water all day and still feel dehydrated.
That's because hydration isn't just about water — it's about the balance of water and electrolytes in your body. Electrolytes are minerals like sodium, potassium, and magnesium. They're what allow your cells to actually absorb and hold onto the water you're drinking, and they're what keep your nerves firing and your muscles working properly.
When you breastfeed, you don't just lose water. You lose electrolytes too — sodium, potassium, and magnesium, are all measurable components of breastmilk [4]. Add in postpartum sweating and hormonal shifts, and the math gets steeper. If you're only replacing the water, your body is essentially trying to rehydrate with an incomplete toolkit.
That's why some moms report feeling foggy, fatigued, or crampy even when they're drinking what feels like an ocean of water. The water is there. The minerals to put it to work aren't.
Signs you might be under-hydrated
A few things to watch for, especially in the first few months postpartum:
- Constant thirst that water alone doesn't seem to satisfy
- Dark yellow urine (pale straw color is the goal)
- Headaches, especially in the afternoon
- Dizziness when you stand up quickly
- Dry mouth or chapped lips that won't go away
- Muscle cramps, particularly in your calves at night
- A noticeable dip in milk supply on hot days or after long stretches without drinking
None of these are diagnoses on their own. But if a few of them sound familiar, it's worth taking a closer look at how — and what — you're drinking.
What electrolytes actually do for nursing moms
When you pair water with electrolytes, three things happen that matter for breastfeeding:
You absorb water more efficiently. Sodium and glucose work together to pull water into your cells faster than water alone — a mechanism called sodium-glucose cotransport. It's the same principle behind the oral rehydration solutions used by the WHO in clinical settings worldwide [5].
You replace what milk-making takes out. Sodium, potassium, and magnesium are all present in breastmilk [4]. Your body has to source those minerals from somewhere, and if you're not getting them from food and drink, it pulls them from your own stores.
You feel more like yourself. Many moms describe the difference as feeling "less foggy" or "less wiped out" after meals and feeds. We can't promise that, and individual experiences vary — but the underlying biology is well-established.
A note on what electrolytes don't do: they aren't a treatment, and they aren't going to dramatically change your milk supply on their own. Hydration can boost milk supply, but supply is influenced by many things — frequency of nursing, latch, rest, hormones, and more. Anyone telling you a single drink will fix your supply is overpromising.
Where Hera fits in
We made Hera Hydration because we couldn't find a clean, no-nonsense hydration drink designed specifically for the demands of motherhood. Most electrolyte drinks on the market are built for athletes — high in sugar, full of artificial flavors, and not formulated with nursing moms in mind.
Hera is built around the electrolyte profile your body needs for hydration, with no artificial sweeteners, no dyes, and ingredients you can pronounce. It's designed to support a healthy milk supply by helping you stay properly hydrated.
If you've been chugging water all day and still feeling depleted, this is probably what your body has been asking for.
Sources
-
Kim, S.Y., & Yi, D.Y. (2020). Components of human breast milk: from macronutrient to microbiome and microRNA. Clinical and Experimental Pediatrics. (Confirms breastmilk is approximately 87% water.)
-
Institute of Medicine (US) Subcommittee on Nutrition During Lactation. Milk Volume — Nutrition During Lactation. National Academies Press. (Average established milk production of 25–35 oz / 750–1,000 mL per day.)
-
Institute of Medicine. (2005). Dietary Reference Intakes for Water, Potassium, Sodium, Chloride, and Sulfate. National Academies Press. (Adequate Intake for total water: 2.7 L/day for adult women, 3.8 L/day for lactating women — roughly 11 vs 16 cups.)
-
Keenan, B.S., et al. (1997). Electrolyte composition of human breast milk beyond the early postpartum period. Nutrition. See also: Bauer, J. & Gerss, J. (2011). Electrolyte and mineral composition of term donor human milk. (Documents sodium, potassium, magnesium, and chloride in breastmilk.)
-
Atia, A.N., & Buchman, A.L. (2009). Oral rehydration solutions in non-cholera diarrhea: a review. See also the WHO ORS guidance. (Sodium-glucose cotransport drives more efficient water absorption than plain water.)
This article is for informational purposes and isn't a substitute for medical advice. If you have concerns about your hydration, milk supply, or postpartum recovery, talk to your OB, midwife, or lactation consultant.
Tags: breastfeeding, hydration, electrolytes, postpartum, nursing moms, milk supply
0 comments