Brazil Nuts for Selenium? I’ve Changed My Mind

“Just Eat a Brazil Nut” The Simplest Advice That Doesn’t Hold Up Anymore

If you’ve followed me for a while, you know I’ve been plant-based for years. And like many of us in the vegan and whole foods world, I’ve said this sentence more times than I can count:

“Just eat one Brazil nut a day for your selenium needs.”

Simple. Convenient. Whole food. Job done.

Except… I’ve changed my mind.

Not because I want to. But because I’ve spent time reading the research. And the most recent studies, particularly the one published in European Journal of Nutrition, have made it impossible to keep giving that advice in good faith.

Here’s the study if you want to nerd out.

The Problem With “Just One Nut” Advice

It turns out that the selenium content in Brazil nuts can vary massively, depending on where they’re grown, the soil they’re in, and a bunch of other environmental factors most people never think about while scoffing a handful.

One nut might give you way more than your daily selenium needs.
Another might give you barely anything at all.

And this is where the well-meaning “eat a Brazil nut a day” advice falls apart.

Because it’s not a reliable source of selenium if you don’t know how much selenium you’re actually getting. And unless you’re a soil scientist with a selenium testing kit in your kitchen… you don’t.

What the Study Actually Found

This new study followed a group of vegans and omnivores, comparing how well their selenium levels improved using either Brazil nut butter or a standard selenium supplement.

The results?

Both methods worked. But supplements were far more consistent. The Brazil nut butter group saw a big range in results, some people improved loads, others barely moved the needle.

So yeah… Brazil nuts can work, but they’re unpredictable. And that unpredictability matters if you’re serious about getting this essential nutrient dialled in.

Why Selenium Matters (And Why It’s a Pain in the Ass to Get)

Selenium isn’t just some bonus mineral to chuck on your supplement list for vibes. It plays a role in:

• Thyroid function

• Immune health

• Antioxidant protection

• Cognitive function

And deficiency? That can show up as fatigue, brain fog, weakened immunity, all the symptoms people think is “just normal.”

So it’s important. But as someone on a plant-based diet, it’s also annoying to get consistently without eating animal products. For a long time, Brazil nuts felt like the perfect solution. And for a while, they were. But now, it’s time to be honest about the gaps in that advice.

So What Do I Recommend Now?

I’m not saying throw Brazil nuts in the bin and block them on Instagram.
They’re still nutritious, and for some people, they’ll be enough.

But if you’re relying on one Brazil nut a day and assuming you’ve got selenium sorted for life, you might want to rethink that.

Here’s what I suggest instead:

Eat a Variety of Plant-Based Selenium Sources

While plant sources of selenium are limited and variable, some options include:

• Brown rice

• Sunflower seeds

• Mushrooms (especially shiitake)

• Oats

• Lentils

• Wholewheat bread

But again they will depend heavily on where they’re grown.

Consider a Low-Dose Selenium Supplement

It’s not un-vegan to use a supplement. It’s smart.

I’m not talking about mega-dosing. I’m talking about plugging a potential gap with a simple, low-dose selenium supplement a few times a week.

Cheap. Reliable. No mystery soil testing required.

Don’t Obsess Over One Food

This is the big lesson.

No single food should carry the weight of an entire nutrient. That’s not how nutrition works. That’s not how life works.

It’s not about demonising Brazil nuts, it’s about getting honest with how nutrition plays out in the real world. And in the real world, eating a wide variety of whole foods, keeping your diet diverse, and supplementing when needed is far more effective than clinging to that one-nut-a-day gospel.

Changing Your Mind Isn’t a Weakness. It’s Growth.

The problem with the wellness world, especially in the vegan space is that we hold so tightly to these one-liners:

“Just eat one Brazil nut a day.”
“Just eat plants, and you’ll be fine.”
“Just avoid supplements, they’re unnatural.”

But guess what?

Nutrition is nuanced.
Science evolves.

And admitting when the evidence has changed your mind is a strength, not a weakness.

So no, I don’t hate Brazil nuts.

But I also don’t think they should be our go-to selenium solution anymore.

Take that for what it is. Not fear-mongering, not overreacting, just updated advice based on better information. And I’ll always choose that over blindly repeating what we used to think was true.

Callum