I’ve been taking 12.5mcg a day T3 now (raised from 6) for about a month on the keto/carnivore diet. It’s been going well I’ve been exercising and getting back to reading books again which has been nice. Carnivore was quite hard so I transitioned over to keto which seemed to help a bit probably because the 30g of carbs will allow some conversion of T4 to T3. I’ve been eating carbs though the last few days due to some celebrations etc and my heart rate today is through the roof! I must have too much T3 now that I’ve eaten carbs again on top of the 12.5mcg I’ve taken. Should I not take the T3 when I know I’m going to be eating carbs? I’m going on a cruise in May for a week and I will definitely be eating more carbs for sure. I’m thinking maybe just stick to the T4 while I’m away? Any thoughts?
My experience of T3 on keto/carnivore so far - Thyroid UK
My experience of T3 on keto/carnivore so far
Hello, I recently stopped eating low carb ie below 30 to 50 grams of carb a day. I was hoping for better sugar control as my HbA1c kept rising.
I had experienced the pounding heart you mention after eating a high carb meal especially if I drank alcohol at the same meal. My Apple Watch once alarmed in the middle of a dinner party as my heart rate had reached 120 while sitting at the table! It said to go to hospital! Very embarrassing.
I had been happily on T3 only for a few years but started to worry about highish blood sugar levels, which is known to be a problem with T3 only & the occasional high heart rate. I changed to 100 T4 & 10 T3 & had ok levels of both, though still a low TSH.
After 4 months on low carb I was horrified to find on testing that my HbA1c level had jumped up nearly 10 points from the previous year & 5 points in 3 months, the opposite of my expectations. It brought me to 47 so just below diabetes.
Why this happened I don’t know although I did find a medical research paper that says low carb & keto can have this effect on lean people.
I think you should check your HbA1c, you may find they’ll do it at the GPs if you tell them about the racing heart rate after eating carbs.
It might be better to reduce your T3 before your cruise but experiment with food first. If like me it’s the combination of alcohol & sugar that sends your heart racing then you could experiment with eating fats & protein ie nuts before you drink to see if it moderates it. The other thing I do is use a Berberine supplement. It’s extremely good at reducing blood sugar peaks & improving your body’s use of carbs. I use Time Health but it’s an expensive one, there are much cheaper ones available.
I’d be very careful about staying low carb long term as it may do more harm than good. I’m now settled on 100T4 & 20 T3 & eating moderate carbs but no gluten & low levels of sheep yoghurt & cheese, & a gin & tonic every evening after a handful of nuts. Everything has settled down & I no longer get palpitations or a high heart rate level at all. I’ll retest everything in a few months 🤞. I’m hoping that my HbA1c has dropped.
I've found in my experience that big sudden swings in blood sugar can often cause temporary palpitations. I don't think it's to do with T3 though, I think it's the body trim to catch up and deal with it. My husband gets it too and he doesnt take T3.