The Two Nutrients Most Breastfeeding Mothers Are Missing (and Why They Matter More Than You Think)

No-one tells you how much of your own health gets parked when you’re breastfeeding. With my first beautiful rainbow baby boy I  thought I was doing everything right. He was thriving & I was so grateful to be able to breastfeed him. Yes, I was exhausted, but isn’t every new mother?

I didn't know then that it wasn’t ‘just’ exhaustion. I was lightheaded more often than I admitted out loud. My nails were so brittle that they peeled when I wore closed shoes. I couldn’t sleep even when the baby slept due to full-blown insomnia, staring at the ceiling at 3am while my body vibrated with exhaustion. And then came the heart palpitations.

Lying in bed at night, feeling my heart race and skip and flutter in my chest. I slept with 999 on the screen of my phone as my partner worked late. It was terrifying. And then one day, I fainted.

I ended up in A&E where they ran tests. Everything came back “normal.” But it wasn’t normal. I was completely depleted.

My body was producing liquid gold for my baby (stem cells, antibodies, live white blood cells, growth factors) and in the process, it was pulling calcium from my bones, iron from my blood, B vitamins, magnesium and omega 3s. Plus two nutrients I’d never even heard of: selenium and choline. This time, I’m doing it differently.

Why Selenium Matters When You’re Breastfeeding

Selenium is a trace mineral with antioxidant and anti-inflammatory properties that plays a pivotal role in thyroid metabolism. Your thyroid gland actually has the highest selenium concentration of all tissues in the body.

I didn’t know back then that research shows that 61-68% of breastfeeding women have selenium intakes below the estimated average requirement and low selenium status has been linked to postpartum depression and thyroid dysfunction. Studies have shown that selenium supplementation during pregnancy and postpartum reduces thyroid inflammatory activity and the incidence of postpartum hypothyroidism. 

Without adequate selenium, your thyroid can’t function properly, which explains the fatigue, the brain fog, the hair loss and even the inability to lose weight postpartum. It’s not just postpartum. It’s depletion.

Why Choline Matters Even More

If selenium was the nutrient I’d never heard of, choline was the one I didn’t know I desperately needed. Choline is present in human milk, and unlike many nutrients that decline after a few months, the supply of choline remains constant across the first year of life, a hint that it’s critically important for infant development.

What choline does for your baby:

Choline is crucial for synapse formation, cellular membrane construction, methylation and the production of acetylcholine, a neurotransmitter essential for memory and cognitive function. Higher maternal choline intake during pregnancy and breastfeeding is associated with better child neurocognition, including improvements in memory, attention and visuospatial learning. Children born to mothers with higher choline levels during pregnancy performed significantly better in tests measuring the brain’s inhibitory function and showed superior behavioural regulation. 

Let that sink in: the choline you consume whilst breastfeeding directly impacts your baby’s brain development, memory and attention span.

What choline does for you:

Your liver is working overtime postpartum, processing hormones, metabolising nutrients and supporting milk production. Choline is essential Choline also supports maternal mental health, improving cognitive function and potentially reducing postpartum depression risk. 

What choline does for your breasts:

Crucially, choline plays a critical role in preventing blocked ducts and mastitis. It is a key component of phosphatidylcholine, which makes up a significant portion of the fat globule membrane in breast milk. This membrane keeps milk fats properly emulsified and flowing smoothly through your milk ducts.

When you’re deficient in choline, the fat in your milk doesn’t flow as well. It becomes thicker, stickier and more likely to cause blockages in your ducts. Those blockages lead to painful blocked ducts, which, if left unresolved, can progress to mastitis.

I didn’t know this with my first baby. I battled recurrent blocked ducts throughout our breastfeeding journey. I thought it was just bad luck or poor latch or too much milk. Again, it was depletion.

Adequate choline intake supports proper milk fat metabolism and keeps your milk flowing freely. It’s not a guarantee against blocked ducts (positioning, latch and frequent feeding still matter), but it’s a foundational piece of the puzzle that most lactation support completely overlooks.

The Problem: Most of Us Aren’t Getting Enough

Studies show only 10% of pregnant women meet the adequate intake for choline, and around 90-95% of pregnant and breastfeeding women have inadequate choline intakes. The recommended amount? 450 mg per day during pregnancy and even more - 550 mg per day - whilst breastfeeding.

For selenium, pregnant and breastfeeding women should aim for 70-80 microgrammes per day, though research suggests a higher intake of 105 microgrammes per day may be optimal during pregnancy. Most antenatal vitamins don’t contain adequate choline. Most postnatal vitamins don’t either. And if you’re moving towards a plant-based diet (as many of us are for health or environmental reasons), your risk of deficiency increases even more.

Where to Get Selenium Naturally

The richest food sources of selenium include Brazil nuts (exceptionally high, just one nut contains about 95 microgrammes, almost twice your daily requirement), seafood like yellowfin tuna and halibut, eggs, lean meats including chicken and beef and whole grains.

A word of caution on Brazil nuts: One Brazil nut contains 68-95 microgrammes of selenium. Doctors suggest taking no more than 400 microgrammes per day to avoid toxicity. Eating Brazil nuts daily can lead to selenium toxicity, so limit intake to a few times per week.

Practical selenium sources:

∙ 1-2 Brazil nuts, 2-3 times per week

∙ 3 oz salmon: ~40 microgrammes

∙ 3 oz chicken breast: ~22 microgrammes

∙ 1 large egg: ~15 microgrammes

∙ 1 cup cooked brown rice: ~14 microgrammes

Where to Get Choline Naturally

The richest dietary sources of choline are eggs (one large egg contains 147 mg, concentrated in the yolk), beef liver (356 mg per 3 oz), chicken liver (246 mg per 3 oz), salmon (187 mg per 3 oz), chicken breast (72 mg per 3 oz) and beef (117 mg per 3 oz).

Plant-based sources include Brussels sprouts (63 mg per cup), broccoli (63 mg per cup), cauliflower (72 mg per cup), kidney beans (54 mg per cup) and wheat germ (153 mg per 3 oz).

The reality: Eggs represent the major source of choline in the UK & US diet. Research shows it is extremely difficult to achieve the adequate intake for choline without consuming eggs or taking a dietary supplement. If you’re eating 2 eggs per day, you’re getting about 294 mg, just over half of what you need whilst breastfeeding.

Why I’m Taking Healthy Mama Happy Baba

I’m 14 weeks pregnant as I wife this and this time I’m not waiting until I’m depleted postpartum to act. Morning sickness (or all-day-sickness) has left me unable to eat eggs at all for months and I am acutely aware that there are nutritional faps in my diet. Healthy Mama Happy Baba contains selenium as seleno-methionine (the most bioavailable form) and choline in their postnatal formula.  Both are included at levels that support breastfeeding mothers without risking toxicity. I’ll be taking their antenatal formula now and I’ll transition to their postnatal formula as soon as this baby arrives. Because breastfeeding shouldn’t mean depleting yourself.

You can nourish your baby and replenish your own body. Your health matters. Your energy matters. Your recovery matters.

Ready to support your body through pregnancy, breastfeeding & beyond? Get 20% off Healthy Mama Happy Baba with code: DANIELLE20.

Let’s normalise mothers actually taking care of ourselves, too.

With love,

Danielle X Healthy Mama Happy Baba

❤️