T Nation

Keto Killing My FT3


For starters, let me give you my stats here:
Female, 19, 120lbs currently (always maintained 100-105), 5ft 1, premed/runner, no pre-existing autoimmune or hormonal conditions

Past diet history: gone from carby vegan of 3 years to zero carb keto overnight (been at it for 3-4 months)

After starting zero carb I started to see problems emerging in the 2nd month. I lost a bunch of hair (Telogen effluvium happens with a diet change so…), my skin got quite dry, my eyes got incredibly dry, eyebrows started to thin out at the sides, major fatigue, depression, cold all the time, very low body temp throughout the day, crazy weight gain… So I realized pretty quickly this sounded a lot like a thyroid issue.

Skip ahead: I got blood work done and everything was completely normal (ft4 and TSH) except for ft3… My ft3 was stunningly low. Now don’t get me wrong, avoiding carbs as we do in keto will lower ft3 because your blood sugar isn’t going crazy. However, my metabolism was botched. Not only was I not losing weight but I was gaining only eating my normal 1100-1300 calories daily (I’m a short girl so I dont need much).

Current position: I’m still researching and seeing a good functional doc to interpret more future blood test. I’m trying to fix the problem with my diet by upping carbs to 50 grams daily and so far my temp and mood has returned to normalcy but I hate the way it makes my brain feel (not as sharp). That being said I know Cytomel is an obvious fix to the low fT3 issue but it won’t cure the root cause, and being that’s it is catabolic in too high of a dosage will only worsen the metabolism if handled improperly.

So my question to you guys: how many carbs should I intake daily to raise my ft3 levels back to normal?


My question is, why didn’t you actually follow the keto diet?


How do you mean? I ate low/zero carb high fat for months whilst focusing on hitting the nutritional milestones (vitamins, minerals, probiotics, fish everyday for omegas, yada yada)


If you want to start adding in more carbs, nobody can tell you how many are right for you. We don’t know your genetics, diet/weight history, stress levels, or training intensity/volume. You may try adding in 25 g/day for week or so, see how you feel, then add another 25 g/day or so. You can be less or more aggressive if you’d like.

This is strictly anecdotal, but what I’ve seen is that keto works really well for some people but is an absolute train wreck for others, especially women.

When something isn’t working for you, it doesn’t mean you need to do that thing harder or stricter. I see this with keto-ers, vegetarians, paleo-ers, vegans, etc. Whatever they are trying isn’t working for them, so they just try to do it more strictly or more intensely.

That said, if you are dead set on keto, you may try checking out Ketogains.


The bare minimum for your stats should be around 2000 calories. Bare minimum. To loose weight.

Again, why didn’t you follow the diet?