The Best Foods to Eat with Hashimoto’s – And Why!

I want to talk about the new year again and what that means for you and all the marketing coming your way. Getting excited about your health is great but I want you to know and understand the real secret to getting healthy is not making big promises to yourself about getting healthy and expecting things to go perfectly all the time. The real magic to your health and wellness is not to quit when life gets in the way and consider it a failure.

The real magic happens when you show up for yourself on the daily and making adjustments as you go, no matter what life throws at you. Life stuff is always going to happen, it’s what you do in the midst of it that matters. Maybe you miss a day or two of solid healthy eating- does it mean you should give up all together? Of course not, it means you get back on that horse and keep riding and forgive yourself for the missteps because there will always be a misstep.

No one has the perfect life where things go as planned all the time. You can prevent some missteps by being prepared with stuff in your fridge ready for you as needed. But when you don’t have the fridge stocked- don’t worry about making mistakes. You can do this.

If you have Hashimoto’s, your immune system is attacking your thyroid by mistake. That causes inflammation – a quiet irritation inside your thyroid gland (the butterfly-shaped thing in your neck that controls energy). Over time, this inflammation can make the thyroid bigger (called a goiter – like a puffy lump you might feel or see in your neck) or damage it so it doesn’t work well.

Functional medicine says food is super powerful. The right foods can calm inflammation, heal your gut (which helps stop the immune attack), and give your thyroid the tools it needs to feel better. Many women get more energy, less brain fog, and even lower antibody numbers just from eating this way.

There’s no one perfect diet for everyone, but most people do great starting here.

Let’s break it down: foods to skip (and why), foods to eat a lot of (and why), and easy examples.

Foods to Skip – And Why They Make Things Worse

These foods can stir up more inflammation or confuse your immune system. Think of them like bullies that make the thyroid attack worse.

Gluten (in bread, pasta, wheat stuff)

Why skip? It has proteins that look a lot like your thyroid tissue. Your immune system gets confused and attacks your thyroid more (called molecular mimicry).

Most people with Hashimoto’s feel way better gluten-free.

Dairy (milk, cheese, yogurt, ice cream)

Why skip? Many can’t digest it well, and it can cause gut leaks or extra inflammation. The proteins in dairy can also look similar to gluten and trigger attacks.

Soy (tofu, soy milk, edamame, soy sauce)

Why skip? It has compounds that can block your thyroid from using iodine or mess with hormone levels.

You might wonder why – isn’t soy healthy for some things? Let’s break it down simply. The science is a bit mixed, but I’ll explain both sides from a functional medicine view (which often says “better safe than sorry” and avoid it).

What’s in Soy That Can Cause Trouble?

Soy has natural compounds called isoflavones (like genistein and daidzein). These act like weak plant estrogens and can mess with your thyroid in a few ways:

They can slow down thyroid hormone making. Isoflavones can block an important enzyme called thyroid peroxidase (TPO). TPO helps your thyroid put together T4 and T3 hormones. Lab studies show this blocking happens clearly.

In animals or people low on iodine (a key thyroid nutrient), too much soy can make goiters bigger or thyroid function drop.

It can stir up the autoimmune attack

In Hashimoto’s, your body already attacks TPO. Some experts say soy might make that worse because it blocks TPO and could confuse your immune system more.

It can block your thyroid medicine

Soy can stop levothyroxine (common thyroid pill) from getting absorbed well in your gut. That’s why doctors say wait 3–4 hours after taking your meds before eating soy.

But Wait – Some Studies Say Soy Is Okay?

Yes! Big reviews of human studies (including recent ones up to 2025) show:

Moderate soy (like a serving or two a day) doesn’t usually hurt thyroid hormones in healthy people with enough iodine.

It might cause a tiny rise in TSH (a thyroid signal), but probably not enough to matter for most.

Fermented soy (like tempeh, miso, natto) might be easier on the thyroid than unfermented (like tofu or soy milk), because fermentation lowers the trouble-making compounds.

Why Does Functional Medicine Often Say “Avoid Soy” for Hashimoto’s?

Many functional experts recommend skipping soy completely – at least at first. Here’s why:

• Even if big studies say it’s “safe” on average, some sensitive people (especially with autoimmunity) feel worse with soy – more fatigue, higher antibodies, or thyroid flares.

• Modern soy is often processed, GMO, or high in isoflavones – different from traditional Asian soy eaten in small amounts.

Why risk it when removing soy helps so many feel better and calm inflammation?

Bottom Line for You

If you have Hashimoto’s, trying a soy-free diet for 4–6 weeks is often worth it.

Many women notice more energy and less puffiness. If you love soy and feel great, small amounts of fermented soy might be okay – but separate it from your meds and watch your labs/symptoms.

Everyone’s body is different. Talk to your doctor or a functional practitioner, and listen to how YOU feel.

Processed foods and sugar (fast food, cookies, soda, chips)

Why skip? They’re full of chemicals, bad oils, and sugar that feed inflammation all over your body – like throwing gas on a fire.

Refined grains and bad oils (white rice, fried foods with corn or canola oil)

Why skip? They spike blood sugar and add more inflammation.

Some people go stricter with the Autoimmune Protocol (AIP) for 30–90 days: also skip grains, eggs, nuts/seeds, and nightshades (tomatoes, potatoes, peppers, eggplant).

Why? These are common triggers that can irritate the gut or immune system in sensitive people. It’s like a big reset to calm everything down.

Foods to Eat a Lot – And Why They Help So Much

These are like kind friends that fight inflammation, heal your gut, and support your thyroid.

Lots of vegetables (half your plate!) – Leafy greens, broccoli, cauliflower, carrots, sweet potatoes, zucchini.

Why eat? They’re packed with vitamins, fiber, and antioxidants that lower inflammation and help your body detox. (Cook broccoli/kale to make them easier on the thyroid.)

Quality proteins – Grass-fed beef, chicken, turkey, wild fish like salmon.

Why eat? Protein builds hormones and repairs tissue. Fish has omega-3 fats that calm inflammation big time.

Healthy fats – Avocado, olive oil, coconut oil.

Why eat? Fats help make hormones and keep inflammation low. Your thyroid needs them to work right.

Low-sugar fruits – Berries, apples, lemons (in moderation).

Why eat? They give antioxidants to fight damage from inflammation, without spiking blood sugar.

Gut-healers – Bone broth (homemade from bones), fermented foods like sauerkraut or kimchi (small amounts).

Why eat? They seal a leaky gut, which stops bad stuff from triggering more immune attacks.

Thyroid boosters – 2–3 Brazil nuts a day, a little seaweed or kelp.

Why eat? Brazil nuts give selenium (protects the thyroid and lowers antibodies). Seaweed has natural iodine (thyroid fuel) – but just a bit, too much can backfire.

Let’s dive deeper into why that’s a great idea for Hashimoto’s, what selenium really does for your thyroid, and why you have to be careful not to get too much. I looked into the research, including work by Dr. Fulvio Ursini (he’s an Italian scientist who helped discover some key things about selenium).

Why Brazil Nuts Are Awesome for Selenium

Brazil nuts are like nature’s selenium superstars! Just one single nut can have 68–96 micrograms (mcg) of selenium – that’s often more than your whole daily need.

The usual daily recommendation is about 55 mcg for adults, but for people with Hashimoto’s, many functional medicine experts suggest 100–200 mcg to help calm inflammation and antibodies.

Studies show eating just 2 Brazil nuts a day can give you as much benefit as taking a 100 mcg supplement – and it raises your selenium levels safely.

Why not more? The amount in Brazil nuts can vary a lot depending on the soil they grow in. Some nuts have way more, so sticking to 1–3 a day keeps you safe. Eat them raw or lightly roasted – no salt or oil added.

What Selenium Does for Thyroid Health

Selenium is a tiny mineral, but it’s super important for your thyroid. It gets built into special helper proteins called selenoproteins. These proteins do two big jobs:

Protect your thyroid from damage → When your thyroid makes hormones, it creates some harmful stuff called hydrogen peroxide (like a bleach byproduct). Selenoproteins act like firefighters – they neutralize that peroxide so it doesn’t hurt your thyroid cells.

This is extra important in Hashimoto’s because your immune system is already causing inflammation and oxidative stress.

Help change inactive hormone to active → Selenium helps enzymes (called deiodinases) turn T4 (the storage hormone) into T3 (the active one your body really uses for energy). Low selenium can mean less T3 and more fatigue.

In Hashimoto’s, studies show getting enough selenium can lower thyroid antibodies (like TPO), improve thyroid ultrasound pictures, and sometimes even lower TSH levels.

Dr. Fulvio Ursini’s Research

Dr. Fulvio Ursini is a big name in selenium science! Back in the 1980s, he and his team discovered and studied a key selenoprotein called phospholipid hydroperoxide glutathione peroxidase (PHGPx for short). It’s one of the main ways selenium acts as an antioxidant to protect cells from damage.

He also worked on regular glutathione peroxidase (GPx), which helps clean up harmful peroxides. This research showed why selenium is so crucial for fighting oxidative stress – the kind of cell damage that happens a lot in autoimmune conditions like Hashimoto’s. His discoveries helped explain how selenium protects tissues (including the thyroid) from inflammation and damage.

The Dangers of Too Much Selenium

Selenium is great when you have the right amount – but too much can be harmful (called selenosis or selenium toxicity).

Signs of too much:

• Hair loss or brittle hair

• Nails that break or turn white

• Garlic smell on your breath

• Upset stomach, nausea, or diarrhea

• Feeling shaky or tired in a weird way

• In really bad cases, nerve problems

The safe upper limit is 400 mcg a day for adults. Going over that long-term isn’t good.

That’s why Brazil nuts are tricky – eating a handful could push you way over.

Stick to 2–3 max, or get your levels tested with a blood test first. If you take a supplement, go for 100–200 mcg (like selenomethionine) and only under a doctor’s watch.

Quick Tips for You

• Start with 2 Brazil nuts a day – easy and natural!

• Get your selenium level checked (blood test) to see if you need more or less.

• Pair it with the anti-inflammatory foods we talked about before.

• Selenium from food (like Brazil nuts) is usually safer and better absorbed than pills.

Drink tons of water and enjoy herbal teas!

How to Make It Easy

Start simple:

• Cut gluten, dairy, soy, sugar, and processed stuff for 2–4 weeks. See how you feel!

• After that, add foods back one by one (wait 3 days each) to find your personal triggers.

• Eat balanced: Protein + fat + veggies at every meal to keep energy steady.

• Don’t forget: This works best with your thyroid medicine, good sleep, and low stress.

Super Simple Day of Eating

• Breakfast: Eggs with spinach and avocado (cooked in coconut oil). Or berry smoothie with coconut milk.

• Lunch: Big salad with grilled chicken, tons of veggies, olive oil dressing.

• Dinner: Baked salmon, sweet potato, steamed broccoli.

• Snacks: Carrot sticks, a few berries, or warm bone broth.

You don’t have to be perfect – just better most days. Lots of women feel amazing on this. Talk to a functional medicine doctor to make it perfect for you.

You’ve got this!

Food can help turn down the inflammation and give you your energy back. One meal at a time.