Podcast about health, wellness, autoimmune disease, Hashimoto's, Psoriasis, hormones, adrenals, nutritional therapy, nutrient dense foods and ways to bring wellness back to a body in dis-ease. Holistic and functional medicine ideals.
Six types of thyroid dysfunction. Episode 39.
What are you making for dinner these days? I share some of what I’ve been eating, talk about batch cooking, and the importance of eating enough fats and proteins to keep your body full longer. Also, did you know there are six types of thyroid dysfunction? Let’s take a look at the characteristics and labs for each to try to make sense of it all.
Welcome to Episode 39. I’m so happy you are here.
I spend a good couple hours cooking several things last night so I would have food to eat over the next week or so. I’ve been trying to double up on meals when I cook so we have stuff to freeze for nights I don’t want to cook.
I made two whole chickens on Sunday night so I had leftover meat for making soup and for putting on salads. I made a double batch of chili on Monday and Tuesday was a big batch of Thai Beef Stew, braised cabbage and I tried out a meatless dish of grape tomatoes, garlic, basil, chickpeas and spaghetti squash. If you tolerate legumes it was an okay dish. I was hoping for more flavor from the chickpeas. I just sautéed the tomatoes in olive oil, smashed them, added the garlic and chickpeas and sautéed a bit longer. Then I added the spaghetti squash and basil and mixed it through.
We are having venison chops tonight with sautéed mushrooms and roasted cabbage.
What are you making for dinner these days? Head over to my website and comment on this post to let me know what your cooking. Look for Episode 39.
Today we are talking about the six types of thyroid dysfunction that cause or result in hypothyroidism so let’s get started.
The thyroid gland is super sensitive to any changes in the biochemistry in our body. It’s job is to perceive even the tiniest of changes in the body and make up for that by changing how much thyroid hormone is released in the body.
This is one reason you can see such different lab values over time.
When these changes in our biochemistry become something that is chronic or constantly happening in the body then there begins to be problems with the thyroid gland and the communication between the hypothalamus and the pituitary gland.
Things like constant blood sugar dysregulation, constant or chronic inflammation in the body, deficiencies in nutrients, poor liver function, toxic burden, low stomach acid, intestinal permeability, poor eliminations and even the use of hormones including thyroid hormones can cause thyroid problems.
Hypothyroidism or low thyroid function can fall into six different types. Some of these may occur at the same time, and it may be that only one of these will require permanent hormone replacement.
1.Primary Hypothyroidism.
This is when there is decreased hormone production by the thyroid gland. So it isn’t making enough T4 or T3. One cause and the most common cause in the US is Hashimoto’s. Worldwide the most common cause of Primary Hypothyroidism is iodine deficiency. (ref) It is also caused by removal of the thyroid gland.
This is a dysfunction of the thyroid gland and this is the one type of hypothyroidism that needs to be treated with thyroid hormone replacement.
If you have Hashimoto’s, you may need medication due to the destruction of your thyroid gland but you also need to understand that this condition is an immune system issue first and a thyroid issue second.
If you catch Hashimoto’s before too much damage is done, you might be able to support your thyroid nutritionally. Sadly, for me, I am still in need of medication. If you do not have success bringing TSH down with diet and lifestyle changes, you will likely need hormone replacement.
Your labs might look like this if you have primary hypothyroidism:
high TSH
normal or low Total T4
normal or low Free T4
normal or low Free T3
normal Reverse T3
2. Secondary Hypothyroidism
This deals with your thyroid not putting out enough thyroid hormone due to an issue in the pituitary gland. Remember that the thyroid is regulated by the pituitary gland and the hypothalamus. When these two glands are not communicating and the pituitary doesn’t secrete Thyroid Stimulating Hormone (TSH) like it is supposed to. You may find your TSH at or around 1.8 but still having symptoms of hypothyroidism.
Chronic stress in the body is usually at the heart of this one. Stress fatigues the pituitary and it can cause a failure to signal the thyroid to produce thyroid hormone.
Stress: too busy all the time, not enough sleep, living off of coffee and processed foods, inflammation, viral or bacterial infections. All of these will mess with your adrenal function and your thyroid function and remember those two go hand in hand.
You can also have low thyroid function after pregnancy. This is a stressful time for women who tend to be the ones suffering with most thyroid conditions. Pregnancy in and of itself will put a high demand on the pituitary gland.
If your blood tests come out normal but your doctor puts you on thyroid medication anyway, it can help you feel better for a couple weeks but then you might start to feel worse. You can develop thyroid hormone resistance at your cells much like insulin resistance.
So your cells are refusing thyroid hormone because there is too much in the blood and you might be given a higher dose making things even worse. You have all this hormone running through your blood so your pituitary gland gets a message it can stop making TSH or it just stops talking to the thyroid altogether.
You might need medication after enough damage has been done between the communication of the pituitary and the thyroid.
If you have Hashimoto’s but it doesn’t get addressed, this can become you.
Your labs might look like this:
1.8 or less TSH
6 or less T4
symptoms of hypothyroidism.
3. Your T4 is not converting to T3
This happens when you have tons of chronic stress and high cortisol. So you are making T4 but your body isn’t converting it to T3 which is what your cells need. When cortisol is high, you will likely have some of this going on.
If your body is dealing with infection or inflammation your cell walls can be damaged by that which also affects T4 to T3 conversion.
You need to damper the inflammation or infection and support your body in dealing with cellular stress (free radicals).
T3 levels won’t affect your TSH so your labs might look like this:
Normal TSH
Normal Total T4
Normal Free T4
Low T3
Low Free T3
Low or normal Reverse T3
4. Your conversion of T4 to T3 is too high.
This would mean you have too much T3 being made and you also have less thyroid binding globulin (TBG).
Too much T3 will overwhelm the cells and you find yourself in thyroid hormone resistance again. It is common in women with insulin resistance and PCOS. It is often caused by too much testosterone in the body. If you have developed Type II Diabetes and are taking insulin for this, you may also find yourself in an over conversion of T4 to T3.
If you are using a testosterone cream you can over convert T4 and T3.
You will have hypo symptoms with this one.
A big help here will be to reverse the insulin resistance to reverse the thyroid hormone resistance and begin to feel better.
You may have labs that look like this:
Normal TSH
High or high normal Free T4
High or high normal Free T3
Normal Reverse T3
5. High Thyroid Binding Globulin
Thyroid Binding Globulin is a protein that carries thyroid hormones to the cells so they can use them. You can develop antibodies to this protein in Hashimoto’s.
You can find yourself in this situation if you take hormonal birth control or estrogen replacement therapy.
If you are on birth control, you may have high levels of estrogen you will make too much TBG and thyroid hormones are carried to the cells on TBG so if you have too many TBG proteins in the blood bound to them, you can have less thyroid hormone getting to your cells.
You have to work to get the excess estrogen out of the body.
Your labs might look like this:
Normal TSH
Low Free T4
Low Free T3
Normal Reverse T3
6. Thyroid Hormone Resistance
Again, similar to insulin resistance with a root cause being stress. Your pituitary gland and thyroid gland may be making just the right amount of hormone but it just isn’t getting into the cells. It feels like hypothyroidism to you and it is the high amount of cortisol in your body that is causing your cells to resist the thyroid hormone.
You absolutely must manage your adrenals with this one.
Your labs might look like this:
Normal TSH
Normal Free T4
Normal Free T3
Normal Reverse T3
You have to make sure your labs are being tested regularly in all cases.
Ok. That’s it for me.
I want to remind you all that I have openings in my practice for a few more clients right now so if you are needing help navigating diet and lifestyle changes head over to Help For Hashimoto’s and fill out the contact form. You can also get my report on Five Things Your Doctor Won’t Tell You About Hypothyroidism.
One last thing, part of the diet and lifestyle changes are to look at what you are putting on your skin. I found Beautycounter to be a trusted source for skin care and make up for me. They ban over 1300 chemicals in their products while the US only has a ban on around 30 ingredients. So, you don’t have to think about safety with their products and I really like that so I became a consultant last year. I don’t work too hard at selling it because my focus is really on nutrition but if you have any interest in checking them out go to beautycounter.com/stephanieewals to shop. I would sure appreciate your support.
I’m still on a social media break and have no desire to get back on anytime soon. I’m checking the Help For Hashimoto’s facebook group once a day. You can join that if you would like but all the action is in the newsletter which you can sign up for on my website.
I’m grateful to you all. Please leave me a rating and review on iTunes so more people can find the show and get help.
Until next time.
Acid blockers, digestion, and elimination. Episode 8.
Terrible heart burn — What helps? Has anybody had any issues with Omeprazole or any acid reducer? Let’s talk about these acid blockers, how hypothyroidism can lead to low stomach acid, and how having less than good digestion is a real big problem for those of us with sluggish thyroids. There are a lot of things you can do to eliminate acid reflux and keep things moving along smoothly. Yes, we talk about poop, too!
Terrible heart burn !!What helps? Has anybody had any issues with Omeprazole or any acid reducer.
OMEPRAZOLE: aka Losec, Prilosec, Prilosec OTC and Zegerid
classified therapeutically as antiulcer agent and pharmacologically as a proton-pump inhibitor
Used for maintenance of healing in erosive esophagitis, duodenal ulcers with or without H.Pylori. Short term treatment of active benign gastric ulcer. The OTC or over the counter is for heart burn occurring more than or equal to 2x a week.
What does it do? it binds to an enzyme on gastric parietal cells in the presence of stomach acid. It diminishes the accumulation of acid in the gastric lumen with lessened gastroesophageal reflux and helps heal duodenal ulcers.
Binds 95% of protein and is metabolized by the liver with a half life of 30 min to an hour. Half life means how long it takes for half of a medication to be eliminated from the blood stream.
It says to use cautiously in liver disease, in geriatric patients due to increased risk of hip fractures in patients on high doses for longer than one year and in pregnancy, lactation or children.
Acid blockers like the ones mentioned and also things like mylanta, maalox, tums alka-seltzer, tagamet, pepcid, zantac etc all will lessen the amount of stomach acid you have in your stomach. So how will you break down your food? That is what it is there for. The acid blockers change the pH of your stomach which is supposed to be very acidic at around 3 I think. This low pH is how we break down our food, especially protein. Protein gets broken down in to amino acids which become neurotransmitter. Stomach acid breaks down our food so we can extract the nutrients we need from it.
Low stomach acid, which happens naturally as we age and most of us with hypothyroidism don’t make enough of it can lead to anemia, candida, fatigue, constipation/diarrhea, tooth decay, hair loss, and a higher risk of developing food sensitivities.
So you have less acid when you take an acid blocker but you also have a deficiency of good bacteria, calcium, coq10, folate, glutathione, iron, magnesium, melatonin, niacin, potassium, B vitamins, selenium, vitamin A, C, D and zinc.
Hypothyroidism can lead to hypochlorhydria or too little stomach acid. This is what often causes acid reflux. When food is not digested well by the acid in your stomach it will putrefy, ferment and become rancid in the stomach. Our small intestine doesn’t like to let undigested or poorly digested food from the stomach enter there so it backs up in to the esophagus, irritating the tissue there and causing heart burn.
Coffee and nicotine reduce the pressure on the esophageal sphincter so you end up with more reflux.
The food is not as acidic as it should be it doesn’t stimulate the gallbladder to secrete bile to emulsify fat and the pancreas doesn’t get signaled to release digestive enzymes to further digest the food. So you have this rotting food moving through the intestines which will eventually cause inflammation, maybe even an infection and likely leaky gut or intestinal permeability.
The fat in the food isn’t being broken down by bile from the gallbladder so your cells are not getting any minerals. Zinc is a mineral which helps us produce enough stomach acid. Having hypothyroidism messes with our gallbladder function and it can cause it to become sluggish and it won’t release enough bile. Combine that with the SAD and you have the perfect storm for gallbladder attacks. When the gallbladder isn’t working well, the liver also becomes sluggish and backed up so it can’t detoxify our hormones, toxins or other things.
So as you can see, having less than good digestion is a real big problem for those of us with sluggish thyroids. Along with zinc, we end up depleted in tyrosine, selenium and vitamin A and D. When it is not working well it plays a role in autoimmune disease as well. Perfect. Look at all we have going for us! We have a large amount of our immune system in our gut- around 60-80%. If our digestive tract is out of wack, inflamed, or if we are dealing with parasites then our adrenal glands will end up depleted. This will make your thyroid sluggish as well.
It just keeps getting better for us.
Ideal elimination from the time you eat a meal to the time it leaves you in the form of a bowel movement is between 16-24 hours. This is slower with hypothyroidism. Constipation is anything longer than what your normal elimination would be. You can end up with malabsorption issues and toxins and hormones get recycled which add fuel to the fire. There is a good chance you will be growing more of the harmful bacteria putting your good guys at risk for being taken over by the bad guys. Remember that we convert some T4 to T3 in the gut but we won’t do that as well when there is an imbalance of bad to good bacteria. 20% of thyroid function relies on the right balance of bacteria.
Another biggie mentioned briefly earlier is the elimination of hormones, particularly estrogen. I am not a hormone expert but I do know that poor digestion means you can end up with higher amounts of estrogen that can lead to hypothyroidism that doesn’t show up on a blood test. This information came from Why Do I Still Have Thyroid Symptoms from Datis Kharrazian. He says that “excess estrogen binds the thyroid transport proteins so that thyroid hormones cannot get to the cells to do their jobs, causing hypothyroidism symptoms”
There are a lot of things you can do to eliminate acid reflux and keep things moving along smoothly.
Food sensitivities or allergies can cause reflux or silent reflux which often has a cough with it.
Look at your diet. As per usual, gluten free, dairy free and an elimination diet are the first place to start. Remove also, eggs, corn, soy and yeast. This will give your immune system a break. A chance to calm down and your gut can repair itself. These foods should be eliminated for 3-4 weeks. The longer the better. Typical food reactions can look like skin rashes, eczema, acne, fatigue, joint pain, bloating, gas, heartburn, constipation, diarrhea and even nasal congestion. You can have anxiety, irritability, headaches and more.
Manage your blood sugar.
Stress. Don’t eat when you are stressed, take a minute to calm down, sit at the table without a phone, book or anything else. Take a few deep breaths, say grace if you like or whatever. Then take a bite of your food and chew it really well. Like 20-30 times per bite.
Don’t drink a lot of water and avoid anything bubbly with dinner. The phosphorus in pop can put you in to sympathetic or fight or flight which will automatically turn off stomach acid production.
You can take digestive bitters about 20 minutes before dinner and if that is not enough you may need to supplement with stomach acid. Something called Betaine HCl. I like a product called Hydrozyme from Biotics Research. I recommend buying it from a practitioner, not off of Amazon.
To find out how much you need you take a bite of food, chew it well, swallow it and then take an HCl supplement with a small amount of water. Take another bite of food, chew it well and take another pill. Keep doing this until you feel a little burn, kind of like heartburn or like you just took a shot of alcohol. If you felt the burn at 3 pills then you know you only need 2 at each meal. Eventually you can get enough healing of your body done that you will start to make more stomach acid and you won’t need to take as much of the supplement.
You can check in on your digestion by keeping a food journal. Write down everything you eat and drink and how you feel afterward. Keep track of your bowel movements. Look at them. Do you see undigested food in your stools? What shape are they? You can google the Bristol Stool Chart and see where you are at and where you need to be. Your eliminations should be solid, about the length of your forearm from your elbow to your wrist. It should come out with no straining, you should not feel like your elimination wasn’t complete and you should not have much on the toilet paper after you wipe.
If you want to test your transit time you can take some activated charcoal pills, like 5 of them or you can eat about a cup of beets, or take 2 tablespoons of sesame seeds. Take them first thing in the morning, don’t chew the seeds if you use them, just swallow them. You want to be able to see them when they come out. Write down what time you take them and what day you take them. Then keep track of your bowel movements. Write down the first time you see the seeds, beets or charcoal (your stool will be black with charcoal and reddish with beets) and write down the last time you saw them in your stool. The difference between the time you swallowed them and the last time you saw them is your transit time. Remember we are looking for anywhere from 16-24 hours. Also, ideally you might go two times a day.
That is it for me today. If you have any questions about this episode or you would like to submit a question for the podcast, please feel free to leave a comment on my website, www.outofthewoodsnutrition.com or www.helpforhashimotos.com or email me at helpforhashimotos@gmail.com
You can find me on facebook at www.facebook.com/outofthewoodsnutrition or on instagram at stephanieewalsntp.
Thanks so much for listening. I really appreciate it. If you enjoy listening to this and want others to have access to it, I would appreciate it if you left a review on iTunes for me. My goal is to help as many people with thyroid problems and Hashimoto’s or other autoimmune diseases and I can’t do that without your help. Please help spread the word.
The first step to getting your life back is believing that you can!
Thanks again. See you next time.
Will going gluten free help Hashimoto’s? Episode 2.
In this second episode, we talk about how our immune system is affected by gluten and why it is important to avoid it to ensure our thyroid can stay healthy. We discuss how to go gluten free, how I went gluten free, and where to find hidden sources of gluten.
In this second episode, we talk about how our immune system is affected by gluten and why it is important to avoid it to ensure our thyroid can stay healthy. We discuss how to go gluten free, how I went gluten free and where to find hidden sources of gluten.
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I have Hashimotos and I’m hypo.
I’m tired of feeling bad everyday. I wake up and go to bed feeling bad. I have no energy throughout the day and I have 3 children to take care of. I’m unable to work due to my anxiety and depression. I have no support at home.
I haven’t my house in 3 days. I feed my children whatever is quick and something I don’t have to stand over the stove and cook. I’m tired of being this way. I’m tired of being tired. It feels like I don’t belong here. I need help—-
LITTLE BY LITTLE, A LITTLE BECOMES A LOT. I have been there. When I was first diagnosed I had a 2 year old and a baby. I remember my tongue feeling heavy and it felt really hard to talk. I remember writing a check and feeling like it was so much effort to move the pen across the paper.
My first best guess is that you are either not on the right dose of medication or you are not able to convert the T4 in your medication to the form your cells need which is free t3.
If you can, search for a doctor willing to test more than TSH which is a test looking at what your brain is telling your thyroid to do. Thyroid Stimulating Hormone is coming from the pituitary gland. When the amount of thyroid hormone in your blood is low, it is stimulated to send a message to the thyroid to make more hormone. When there is too much thyroid hormone in the blood it is stimulated to tell the thyroid to make less. So when you have a high TSH (mine was 150 when I was first diagnosed and then the doctor was happy with it around 5 despite the fact that I still felt terrible) it means you are in a hypothyroid state or your thyroid has been told to slow down. When your TSH is really low that means you are in a hyperthyroid state and your thyroid has been told to speed up. The reason why your number is what it is, is dependent upon your bioindividuality. TSH can vary from day to day as well so when you go in, you are getting a picture of how things are working at that moment. This is true of many blood tests. The other problem here is the way the lab ranges were made. The “normal” range was set based on a group of healthy and sick patients. Some with thyroid conditions, and some without so the range is not necessarily based on healthy people. Most healthy folks have a range at or around 2.5. Personally, I am feeling much better at just below one. I am on compounded medication though and so that makes the TSH test result lower than normal. The problem is your doctor may have a lab range that shows 8 as normal which for most people will make you feel sluggish, tired when you wake up or need to sleep 10-12 hours or more, gain weight, lose hair, feel cold and generally not feel well. This is why it is so important to find a practitioner who will treat you based on your symptoms and not just on your labs. Take note that a normal or low TSH number doesn’t mean you don’t have low thyroid function.
Free T3 and Free T4 measure the levels of the active hormone in your body. Free T3 is a more accurate indication that your thyroid is working properly. The free in these means they are available for your body to use.
Depression is really common in people who are on T4 only medications. If that is the case for you, switching to a Natural Desiccated Thyroid Hormone Medication could help you out a lot. Before you even do that though, you really should take a look at your diet. If you body is not nourished it can’t do what it needs to do because certain biochemical processes in the body need certain nutrients to do their job. For example, the enzyme that makes T3 free for the cells to take up is very sensitive to things like malnutrition, inflammation and toxicity in the body and will not work as well.
The major nutrients needed to make our thyroid work well are: iron, B12, vitamin A, vitamin D, magnesium, selenium, zinc and iodine.
TPO Antibodies (Thyroid peroxidase)- this is an enzyme that is needed to produce thyroid hormone.
TG Antibodies (antithyroglobulin)- this is a protein carrier for your thyroid hormone.
These two mean your immune system has produced antibodies to attack because they perceive a problem. When these are present, it can make using the other labs useless because an unmanaged autoimmune condition can cause you to swing between hyper and hypo.
What are your symptoms?
What I am seeing here for your symptoms are no energy, basically tired all the time, and anxiety and depression. You also state you have no support at home. I’m sorry. That makes it especially hard and I get how you feel. I didn’t have a lot of support in the beginning either. I suffered for years and my family suffered because I suffered. My kids, between toddler and early teenage years had a mom who had zero energy. who was angry all the time, who didn’t sleep at night and therefore was totally crabby. Everyone felt like they had to walk on eggshells around me and I have a lot of guilt over that. It took changing my diet without support for me to really see a change in my mood and my energy. Figuring out which foods were sucking the life out of me helped a lot.
So, diet first. You can manage the autoimmune portion of the thyroid (the hashimoto’s) with nutrition. Start with gluten free, then dairy free and then you would want to consider an autoimmune protocol diet/elimination diet. You probably will find that the changes in diet will be life changing for you.
You may need to take some supplements as well. Get your vitamin D checked to see if it is low and if you supplement with it, monitor your levels to make sure you don’t over do it.
A lot of us will have iron deficiency as well. Get a full iron panel, especially ferritin. You need a ferritin level of around 75 for T4 to convert to T3. If you have a ton of inflammation you might have high levels of ferritin so as you change your diet, and reduce inflammation in the body, you should have this checked as well.
Almost all of us are magnesium deficient. It does a lot of stuff in the body.
We need selenium for enzyme systems in the body that help the thyroid work well. Chelated selenium is recommended at a dose of 100-200mcg a day.
Zinc- important for us to make enough HCl to digest our food but also important in T4 to T3 conversion as well.
It is also very important to manage your blood sugar. This can be done with diet and I often find people need support to do this but if you can do it on your own, great.
You may need fish oil and a B complex as well but I recommend working with someone to figure out just what your body needs.
Best of luck to you on your journey.
NEXT Q
Hi. My insomnia, fatigue, and short term memory problems have been really bad lately. I don't know what to do. My newest endo wants me to chase down a whole bunch of other possible reasons for my symptoms. I suppose there's always a possibility that I've developed another autoimmune disease that causes the same symptoms. But, I'm exhausted. I feel like I'm being sent down a rabbit trail that I'll never get off of. I need something that works. Tell me honestly, how much better did those symptoms in particular improve with diet and exercise? I hate always feeling this way.
Does anyone ever have issues controlling the temperature of your body? Like being too hot or too cold? Is this part of Hashi’s?
I was diagnosed with hashimotos after my daughter was born a little less than 3 years ago. My whole life I was a size 5 and now I’m a size 14 and can’t seem to lose weight. My levels seem to like to jump around a bit but currently are level.
What I want to know is what do you do about the lack of energy? I have no energy. I don’t even know where to start with diets or what to do. What are diets that have helped? Anything!!! My energy is so low that I can barely get up some days. Also all I have currently is a family doctor. Should I be trying to get connected with another kind?
Diet- yes diet helps. AIP, Paleo, gf/df, sugar free, managing blood sugar. Find a practitioner to help you.
Diet will help with weight and energy
Temperature issues can be related to the kind of medication you are on. Natural Desiccated Thyroid hormone can help with this. Either way you are probably not on the right dose of medication and/or it can be that your have low iron. Eating meat and liver especially is a great way to get liver from diet. Low iron is a big deal for us. I said earlier that ferritin is super important here but a full iron panel is very helpful. TIBC or total iron binding capacity is measuring the ability of transferrin to bring iron to parts of your body. This will be high when your total iron stores are too low. Serum iron measures what is circulating in blood on transferrin. Next you want to look at the percent of saturation. If this is low, supplementation may be needed. If you need to take a supplement of iron you should be monitored by your doctor as you can get too much.
Another option here is that you could have an issue with your hypothalamus/pituitary axis. Working on your thyroid and adrenal health will help this a lot. Our adrenals are directly related to the HPA axis, play a big role in managing our blood sugar and also help us respond to stress. If you have any amount of chronic stress at all and consume the standard american diet then you likely will have an issue with this. Diet, again is so important here.
I see so many people struggle with making diet changes and I just want to say that you can do it. YOu have to want to be well more than you want to be sick. You have to want to let go of what is a crutch for some of us- we are not our disease, it doesn’t have us. We can manage it.
Pork Patties with sweet potatoes recipe
Chicken Hashbrown recipe from The Healing Kitchen
Hidden Sources of Gluten in The Paleo Approach
Introduction: Help For Hashimoto's Podcast. Episode 1.
In this episode I introduce myself and we talk about the thyroid gland. What it does and why it is so important.