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Thyroid UK
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Fitness and underactive thyroid

I have been taking levothyroxine for over 10 years now and my results are fine (due for another blood test in a couple months so we'll see if they are still ok). I feel good, not tired at all but I do "struggle" with my weight. I can easily put on half a stone on in a very short period but loose it as well within a week or two. At the moment I am 7 stone 9 and 5 foot 3 which I am fine with. However, my body fat percentage is very high (36%), therefore I am looking to loose body fat and gain muscle. I have changed my diet recently, cut down on carbs and sugar and eating more meat and vegetables. I work out 4-5 times a week and trying to walk to work and go cycling as often as I can.

I have been doing some research on protein shakes and come across with something that I didn't know until now. Most protein shakes contain soy protein which is isolated from soy beans. Soy products can interfere with the absorption of levothyroxine from the gut.

Can anybody recomment / suggest protein shakes that will not interfere with the levothyroxine or mess up my hormones? Many thanks in advance.

28 Replies

Probably best to make your own - there must be loads of recipes out there. Are you sure you are optimally treated with T4 ? - Is it converting into the ACTIVE T3 ? How are your levels of B12 - Ferritin - Folate - Iron - VitD ? All these need to be OPTIMAL and could be causing problems if not as it will affect the conversion of T4 into T3....


Hi Marz, thanks for the reply. I will try and bring forward my blood test and make sure I receive a copy of the results. I am normally low on Iron and probably VitD because I have vitiligo so I need to be careful when the sun is out. Is it enough If I ask my GP to test those you mentioned above ( so T4, T3, TSH, Iron, B12, Ferritin, Folate and VitD)? Or should I ask for something else?


I think Vitiligo is auto-immune in response. I too suffered prior to being diagnosed with Hashimotos in 2005. I now live in Crete and have no problem with the sun - in fact I tan better than ever now that my health has improved. Could it be you have Hashimotos - auto-immune thyroid illness - which would explain things a little.

So the Tests are TSH - FT4 - FT3 - Anti-TPO - Anti-Tg for the Thyroid....

B12 - Folate - Iron - Ferritin - VitD for encouraging your wellbeing and improved conversion of T4 into T3. I am suspecting your FT3 will be low and the VitD - also B12. VitD is not just a vitamin but a steroidal pre-hormone and there is a receptor for D on every cell in your body. That is an awful lot of VitD :-) The same for T3....

Let's hope your Doc will do these tests for you - they are all watching their budgets...so lots of charm will be required.... :-)


Will give my GP a call later on today, see what I can achieve ;) Thanks Marz.


...sorry to nag :-) Just know how difficult it is sometimes to have all the pieces of the jigsaw.... Wishing you well....


Appointment is booked for next week so will keep you all updated. (if you want) :)


...that would be good. Just hope he is co-operative... Good luck :-)


Thank you. :)


There are good whey shakes available but you probably don't need them, as Marz says.

Are you lifting weights? Lifting heavy weights is a good way to build muscle and burn fat. If you can, start out at the gym where someone can help you. A good book like "New Rules of Lifting" or "New Rules of Lifting for Women" may be helpful. That's what worked for me in the past anyway :) I probably ought to get back to it!

Of course you should check with your doctor if you have any doubts and be careful if you have any muscular-skeletal issues.

Carolyn x


Hi Carolyn,

I cannot really afford to pay £40+ every month to go to the gym and I probably won't have enough time to use it to make it worthwhile. So I work out at home. :) Have a few Beachbody workouts that I really enjoy. I am planning to start weight lifting but not sure where to start.

My diet has improved but I'm still worred about the fat I have inside me :( I guess I am what you call a "skinny fat" :( x


I know what you mean about the gym! That's why I got the book I mentioned. If you prefer body weight exercises or can't afford the weights, "Convict Conditioning" is another good one. You start easy with many reps and gradually move on to more difficult exercises.


I will look into these thank you. :)


rhetty, if you modify the diet to eliminate sugar and easily digested carbs (more sugar effectively), then it takes months to build muscle and change body fat percentage. Don't go too fast because you will lose muscle mass at the same time and defeat the purpose. How low do you want to go? Women must have a certain amount of body fat of the sex hormones get reduced. Some locations of body fat are extremely resistant: thighs, hips, buttocks.

Why do you want to drink protein shakes as opposed to just eating high protein foods? Your daily protein requirements are somewhere between 70 - 90 grams. Animal protein is well absorbed. Eggs, meat, fish, dairy - all fine. Fish like sole, haddock, cod are all very high in protein, low on fat (depends how you cook them of course.) The body does require fat to function properly so don't go too low fat.


Sorry gabkad, are you suggesting not to cut out carbs and sugar? According to those hand held body fat analysers, my body fat is 36% which is in the "obese" category. Tbh it scared the hell out of me because I thought I had a healthy diet. I think the avarage body fat range for a women is between 25 - 31% so I definitely need to loose some fat to be in the "healthy range".

I do eat eggs, fish, white meat and diary a lot but my protein is only 50-60g daily which is not enough. That why I thought about protein shakes.


No, I agree, cut out empty nutritionless calories. Definitely. They just displace nutrients in the diet. I guess your 'serving' sizes for protein containing foods is low then. The adrenal support diet (which I followed but it was useless when the thyroid level was inadequate) suggests eating protein all three meals per day.

There's these 'whey' based shakes but I haven't kept track of whatever controversies there are about them. The body builders use them. I don't know enough up to date information though.

Even though the accessible protein in pulses is not high, they do provide a complex carbohydrate source of food and prevent blood sugar bounces. (of course not the tinned stuff in the sugary tomato sauce). Helps with pooing too.

A big salad with lettuce, seedless cucumber, spring onion, mini tomatoes, a tin of tuna (in olive oil) plus half a tin of chickpeas and lemon juice is a pretty decent source of vegetables, fibre, slow burn carbs and protein. You can even add capers, olives and hard boiled eggs..........yum. That's my 'go to' supper when cooking is 'off the menu'. I mix it up in a big bowl and chow down.


Thanks gabkad. :) I seriously cut down on carbs and sugar in the last couple of weeks and trying to eat 5 or 6 times a day. I eat bread max 2 times a week, allow myself 1 small bag of crisps a week (used to be 1 a day for lunch), I only eat brown rice and wholegrain pasta probably once a week. The rest is veg and meat. Oh and I eat loads of eggs and nuts (almonds, walnuts, pecan nuts). 1 fruit a day. No fruit juice (or maybe on occasion). I don't smoke and I very rarely drink alcohol so I don't understand why my body fat is so high. :(

ah well, I see my Gp next week so will ask him to do a body fat test :(


Have you considered weight/resistance training?


I am seriously thinking about starting weight training but not sure where to start ie. what weight. Any advice?


Get 2x2 pounds weights and do repetitions of 10-12 to work your biceps, triceps and shoulders muscles. Do few lunges and squats. stretch afterwards. Start with 5-10 minutes. Work on muscles movements and be careful not to just lift with momentum.

Alternative is resistance bands. They come with different stiffness/resistance. Start with medium strength.

There are some exercise videos on YouTube. Seek what fits best with your needs.

Eliminating wheat, grains, and sugar, totally, is giving good results for many people who have far more weight to lose than you. Give it a go, too??

I have read "Wheat Belly" and "Grain and both talk about the importance of eliminating all of these to gain lots of benefits. Weight loss is one of the benefits.

You can do it!


Thanks Melanie. I don't really want to loose weight, just body fat. Tbh I could do with a little more in weight but first of all, I would like to be healthy and fit. :)

I read wheat belly too, that's why I cut down on bread, rice, pasta and potatoes.

I will invest some money into weights ;) I have plenty of exercise videos luckely. :)


Excellent, you'll be fit with toned muscles in just few weeks.

I have bought the 2 kgs x 2 weights and 4 kgs. I shouldn't have skipped the 3kg :-)

Great choices on Amazon and there were no additional charges for postage. Have a look at these to start with



I use Neoprene



Thanks Melanie.

I am doing PiYo 4/5 times a week at the moment (Pilates & Yoga combination by Beachbody). It's great but not enough. I will get a couple weights :) how often should I do it?


Start with every other day for 10-15 minutes until you build some strength. Increase repetitions and time by an increment of 5 minutes each week sticking with one day rest between sessions. See how you feel after 3 weeks.

I go for a brisk walk of 30 minutes followed by weights. I have build up the weights to 20 minutes 4-5 days/week.

On the days that I feel I am not up to it, I simply do as much as I can with a rule of 5 minutes as a minimum :-)


Cool, I will give it a try :) x

Do you take any supplements at all? ie. protein shakes etc.


I take lots of supplements. I have checked out the protein shakes etc and decided not to use them.

Supplements: b12, b6, b1, iodine, iron, selenium, zinc, magnesium, vitamin A, fish oil, EPO,, astaxanthin, vitamin c and I have added b-complex recently taking into consideration the maximum limit of B1 and B6.


Hi Rhetty,

If you have some Beachbody workouts then have you heard of Shakeology? The Vegan is soy-free. I take it everyday for breakfast because it is quick and has a ton of nutrients in it. I am not a coach, so I am not trying to sell you anything. I have noticed an improvement in my energy and in my junk food cravings since starting it 4 months ago. I also do Piyo for strength. It uses your own body weight to build muscle. Any of the other workouts (and I have them all) exhaust me for days. I am not at optimal dosage on my thyroid meds, but I am hoping once I reach optimal I will be able to go back to doing the aerobic programs. I agree that you should have your T4, T3, TSH, Iron, B12, Ferritin, Folate and Vit D checked to make sure that your body is not working against you.


I thought shakeo wasn't available in the UK. Where do you buy yours and how much for, if you don't mind me asking?


Sorry, I forget that in some countries it is harder to get things than here in the U.S. I had no idea that it was not sold all over the world. I see on their website that they are working on the approval process for the U.K.


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