Synthroid vs. the iron in Huel?


First thing, which is unrelated to the actual topic – Huel has been AMAZING for me so far in terms of binge eating. I had a theory that I would binge because my body wasn’t getting what it needed. A few days of plugging in my meal prepped meals on confirmed that I was lacking a LOT. I plugged Huel in and got everything I need – and I’ve already lost 9lbs, binge free.

So Huel is a keeper for me. With that in mind, I am concerned about the iron with my synthroid.

I take synthroid in the morning, and I’m already supposed to wait an hour after taking it before I eat. However, there is also a warning not to take an iron supplement within 4 hours of taking synthroid.

Huel does have a lot of iron (which I’m thrilled about, because I’m constantly low), but since I have it for breakfast, is this an issue?

Can anyone speak to this? I can’t see the doctor for another 2 months, so that’s why I’ve come here.


I just did a bit of reading about sythroid, which I hope you have also done… right?

So it looks like the suggestion is to wait 1-2 hours after the sythroid for it to get far ahead of your food so it can be absorbed in intestines. Regular breakfast then spends some time in the stomach before it moves into the intestines and hopefully the sythroid would be mostly absorbed by then.

I also read that synthroid would rather attach itself to minerals like iron than to be absorbed, which would make it much harder for the body to use it (or even impossible)

Now I wonder if the 4 hour time recommendation between synthroid and iron supplements is due to how available the iron supplement would be (considering that it would be a huge amount in either pill or liquid forms) compared to the availability of iron in Huel. Huel has extra iron because they compensate for phytic acid from oats that might otherwise combine with iron (it turns out a lot of things like to grab onto iron, locking it up in molecular bonds)

So, I don’t know if you can go 4 hours from wakeup+meds to wait for breakfast or if you can do only 2 hours, counting on Huel as more like food than an iron supplement - but you probably know how you feel with and without the full and proper effects of the synthroid… are you noticing that you might be adversely affecting absorption?

You will definitely want to discuss your numbers with your doctor if you are getting better nutrition than you used to get. A metabolic panel might show a very different picture after 2 months using Huel to get nutrition you might not have been getting from your diet last time you saw the doctor.

I hope this helped. I’m not a doctor and I can’t really give any sort of official doctor-y opinion. I am curious though what your doctor says, so please do post an update then. :slight_smile:


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Many clinics/doctors offices have ways for you to ask questions of your doctor without seeing them, often through an Internet portal, but you could also probably call and leave a message with the doctor’s nurse who will get back to you with the answer.

Just be sure to let them know how much Iron is in the amount of Huel you will be consuming and how soon you will be taking it after your meds. I except you will be able to get a preliminary answer this way, though (and I’m only speculating) Huel itself may raise questions and become something you discuss in an appointment.

If really get a hold of you doctor, this seems like the sort of question you could ask of your pharmacist.


Thank you for bringing this up…I had no idea as I was never educated on my diet while taking synthroid. I will have to change my dosing habits. I use Heul for breakfast and lunch, with a regular meal for dinner. Thinking I will have to switch to taking my meds before bed.

Again, thanks for the heads up!


Funnily enough, I cannot for the life of me figure out how to sign back in. The email updates for the thread keep coming, but it isn’t letting me sign in via Facebook and it says my email address (the one Huel forum is sending the thread updates to) is not in their system?

So anyway – it says I can reply to the thread by replying to the email. This may be my last reply if I can’t figure out how to log back in, though.

Yes, I switched my Synthroid to bedtime, not eating after 6pm and taking the Synthroid somewhere between 11 and 12. I couldn’t have waited four hours in the morning for my morning Huel.

Thanks for all your responses and advice! Fingers crossed for the next labs, hoping to have a lot better numbers going forward!

So glad I found Huel.

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Been a hospital pharmacist for 17 years now. I just looked at the Huel nutritional information. A single serving has only 5 mg of elemental Iron in it. In my opinion, taking the levothyroxine an hour before consuming Huel should probably be good enough. 5 mg of Iron is about the same as what you’d find in many typical breakfasts.

Iron supplements, such as Ferrous Sulfate 325 mg, contains 65 mg of elemental iron per tablet. For example, an anemic patient might be on Ferrous Sulfate 325 mg twice or thrice daily, taking 130 to 195 mg of elemental iron each day. This is almost 8 to 10 times the amount of the recommended daily allowance for the general public. So, iron supplements are much much higher than what you get from food and/or Huel.

Remember than any poly-valent cat-ion such as Magnesium, Calcium, and Iron can actually bind levothyroxine in the gut. But unless you are taking a specific supplement that has high amounts of these, taking the Levothyroxine 1hr ahead of a meal is fine for food or food powders. In the hospital, all levothyroxine orders have a standard administration time of 1 hour before the breakfast time for that corresponding floor.


Hi @Deron!
Thanks so much! I was worried about this topic once it was pointed out. I just called my Dr on Friday. After reading the label to him, he basically told me the same thing you just did. :slight_smile: Very helpful, thanks again.


Excellent. Yeah, the labeling for Synthroid advises to separate administration time from “iron supplements”, but it doesn’t really clarify or elaborate on what it considers an iron supplement.

If you look at the labeling for a typical cereal such as Special K, it contains about the same amount of elemental iron as one serving of Huel. Since you wouldn’t necessarily separate Synthroid by 4 hours from your Special K breakfast, in the same light it’s not necessary to separate Synthroid from Huel by 4 hours. One hour should be good enough.


@Lauren_ready I also had this issue. Apparently there are two forums, one is and the other is I signed up for one and then got confused when I couldn’t log into the other, not knowing it was a different one altogether. I made an identical account in both. Not sure if that is what is happening to you. But I Hope that helps.

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Hi @Lauren_Reaney

This article is not yet on the US website (I’m working on it). It only applies to the EU formula, however, there is some useful info there. To view it, you may need to click the UK flag icon (don’t forget to go back to the US flag afterwards!)

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Hi, just an idea…I take my thyroid meds before bed…then I don’t have to wait for food or vitamin reactions :two_hearts:

For anyone else with this issue who is considering taking their pill at night and doesn’t realize the interactions thyroid medication has…

Just as you would do in the morning, take it on an empty stomach including foods, drinks, supplements, vitamins, and meds.

Thank you for this thread. This was one of my concerns as well. I’m looking forward to getting my first delivery!