What is Hypothyroidism
Feeling unusually tired, sluggish, struggling with unexplained weight gain, or noticing changes in your hair and skin? These might be subtle signals that your thyroid gland is trying to get your attention. Hypothyroidism is a common condition where your thyroid - a small, butterfly-shaped gland at the base of your neck - doesn't produce enough thyroid hormones.
These hormones play a crucial role in regulating your body's metabolism, influencing everything from your energy levels to digestion, mood, and overall well-being. Think of your thyroid as your body's "engine." When it slows down, many of your body's functions slow down with it.
Causes and Risk Factors
Hypothyroidism can occur for many reasons. Some of the most common causes include:
- Hashimoto's thyroiditis (an autoimmune condition)
- Radioactive iodine (RAI) treatment for hyperthyroidism
- Thyroid surgery or removal
- Radiation therapy around the neck or head
- Certain medications, like lithium or amiodarone
- Pregnancy (postpartum thyroiditis)
You may be at increased risk if you are a woman over 50, have a family history of thyroid disease, or have other autoimmune conditions, such as type 1 diabetes or celiac disease.
Common Symptoms of Hypothyroidism
If you're experiencing several of these symptoms, it could indicate an underactive thyroid:
- Fatigue and tiredness
- Unexplained weight gain or difficulty losing weight
- Feeling cold even when others are warm
- Dry skin and brittle nails
- Thinning hair or hair loss
- Muscle cramping
- Muscle weakness or joint pain
- Depression, moodiness, or brain fog
- Constipation or digestive troubles
- Irregular or heavier-than-normal periods
- Puffy face or swelling around eyes
- Slow heart rate
Symptoms may start subtly and gradually become more noticeable. It's easy to dismiss these as normal fatigue or stress, but if they persist, it's worth discussing with your doctor.
My Experience With Symptoms
It was probably around two months after my RAI treatment that I started to notice a shift. I was gaining weight that wouldn’t budge, and I began experiencing severe muscle cramps (worst I’ve ever felt) – there were other symptoms but those two symptoms were the worst for me at the time.
The cramping was intense and constant. Even something as simple as yawning would cause my face to seize up. I was cramping everywhere - legs, arms, hands, feet, back, neck - you name it, it cramped. It was exhausting and painful.
I was started on a low dose of Levothyroxine Sodium (25 mcg) - known by many as Levoxyl - but the cramping didn’t let up right away. It actually continued for a few more months. Gradually, things improved as my dose was increased and while the cramps are mostly gone, my hands and feet still cramp up occasionally, usually under certain conditions like dehydration or overuse.
Along with the weight gain and cramping, I also started experiencing intense joint pain in my feet. It got so bad at times I couldn’t walk - I’ve never felt anything like it before. I even had to use crutches and borrowed a medical boot from my brother-in-law just to get around. Thankfully, that pain also started to ease as my thyroid medication was adjusted.
How Does Hypothyroidism Feel?
Imagine feeling drained, sluggish, or constantly exhausted - even after a full night's sleep. Perhaps your mind feels foggy or you struggle to concentrate. You may notice unexplained weight gain despite no changes in your diet, or feel chilly even in warm rooms. Emotionally, hypothyroidism can lead to feelings of sadness, anxiety, or irritability. If this resonates, you’re not alone - your thyroid might be trying to communicate with you.
Even if your lab results fall within the "normal range," it doesn’t always mean your thyroid is working optimally for you. Many people still experience weight gain, hair loss, fatigue, and brain fog even when their Free T3 and T4 levels are technically "normal" (this is what I have been experiencing). It’s often about more than just falling within the range - it’s about finding the right balance for your body.
Some people feel best when:
- Free T3 is in the upper third of the normal range
- Free T4 is in the mid-to-upper half
- TSH is between 0.5 and 2.0, especially after RAI therapy
If your TSH is still high, even after being on medication like Levothyroxine (Levoxyl), it might indicate your body still needs more support or that it's not properly converting T4 into active T3. It’s worth asking your doctor to take a closer look, especially if symptoms haven’t improved.
TSH Lab Ranges
Most labs say a "normal" TSH level falls somewhere between 0.4 and 4.1 - and technically, results in that range are not flagged as a problem. But many people (myself included) still feel lousy even when they’re within that range, especially if their TSH is on the higher end.
- Low TSH = hyper (too much thyroid hormone)
- High TSH = hypo (not enough thyroid hormone)
Some doctors and thyroid specialists believe that an "optimal" TSH range is more like 0.5 to 2.0, especially for people already on thyroid medication. So just because your labs look "normal" doesn’t always mean your thyroid is working as well as it should be. If you’re still dealing with symptoms, it might be worth talking to your doctor about whether your TSH is truly in the right range for you.
It’s also important to remember that different labs may use slightly different “normal” ranges. For example, one lab might say 0.4–4.1, while another lists 0.4–5.0.
Hypothyroidism After Radioactive Iodine (RAI) Treatment
Sometimes hypothyroidism develops after receiving radioactive iodine (RAI) therapy, typically used to treat hyperthyroidism (an overactive thyroid). RAI therapy intentionally reduces thyroid hormone production, often leading to a permanently underactive thyroid gland.
Symptoms following RAI induced hypothyroidism are identical to naturally occurring hypothyroidism, but there are some key points to consider:
- Hypothyroidism can develop gradually, sometimes weeks or months after treatment.
- Lifelong thyroid hormone replacement medication (usually Levothyroxine) is typically necessary.
- Regular blood tests and doctor visits are essential to monitor and adjust hormone levels as needed.
After RAI, your thyroid is no longer functioning, so every bit of thyroid hormone has to come from your medication. This can make finding the right dose more difficult (my doctor and I are currently struggling to find the right dose). Sometimes, the body also struggles to convert T4 (the inactive form) into T3 (the active form). If this is the case, your provider may consider a combination treatment or adding liothyronine (T3) to your regimen.
Additionally, factors like gut health and nutrient absorption (especially low iron or magnesium, or taking your medication too close to coffee or supplements) can interfere with how well you absorb and use your thyroid medication.
The good news is that supportive measures like dietary changes, lifestyle adjustments, and natural remedies are equally beneficial for managing hypothyroidism after RAI therapy.
How Is Hypothyroidism Diagnosed?
Diagnosing hypothyroidism is straightforward and involves:
- Discussing symptoms and reviewing your medical history with your healthcare provider.
- Blood tests measuring levels of TSH (thyroid-stimulating hormone) and T4 (thyroxine) to confirm the diagnosis.
Most diagnoses start with TSH and T4 bloodwork, but if symptoms persist, even with medication, it’s helpful to go beyond the basics. Think about asking your doctor to check:
- Free T3 and Reverse T3
- Ferritin (stored iron)
- Vitamin D, B12, magnesium, and zinc
- Cortisol and estrogen (especially if you’re dealing with fatigue or hot flashes)
These extra labs give a broader picture of what’s happening in your body and can help tailor your treatment more effectively.
Early diagnosis means faster treatment and relief from symptoms.
A Note on Biotin and Thyroid Tests
If you take biotin (often found in hair, skin, and nail supplements), it can interfere with the lab results with thyroid blood tests. Biotin doesn’t actually change your thyroid levels, but it can make the lab results look misleading - TSH may appear falsely low, while free T4 and T3 may look higher than they really are.
I think it was around my third blood test when it showed that I had severe hypothyroidism. Around that same time, I started noticing my hair was falling out more. I had always shed some hair when washing or rinsing, but now it was coming out faster and my hair was thinning a lot. To try and help, I started taking biotin on a daily basis and I was taking at least 2,500 mcg a day. What I didn’t realize then was that biotin could throw off my thyroid labs - and it did. I was suddenly back on the hyperthyroid side, which made things more confusing - and sent me digging into more research, which is when I finally found the information on biotin.
This matters for hypothyroidism because your medication dose is usually adjusted based on these results. If the labs are skewed, it might look like you’re taking too much thyroid medicine when you’re not. Studies show this happens most often with higher-dose biotin supplements (like 5,000–10,000 mcg or more, often marketed for hair and nail growth). In one study, people taking 10 mg daily for a week had thyroid results that looked abnormal, but their numbers returned to normal within 2–3 days after stopping biotin.
The American Thyroid Association recommends stopping biotin for at least 48–72 hours before thyroid bloodwork so your results reflect your true thyroid function.
This just goes to show how important it is to tell your doctor about all the supplements and medications you’re taking - even something as simple as a hair and nail vitamin.
Can Hypothyroidism Affect Vision?
While not everyone with hypothyroidism experiences eye symptoms, the condition can subtly affect vision and eye comfort in several ways:
- Dry eyes: Reduced tear production is common, which can lead to eye strain, irritation, and blurred vision.
- Puffy eyelids or facial swelling: Fluid retention can affect the tissues around the eyes and even cause pressure that affects vision.
- Slowed metabolism: Can affect the nerves and muscles controlling the eyes, leading to fatigue and difficulty focusing.
- Eyebrow thinning: While not vision-related, this is a classic sign and may accompany other subtle eye changes.
- Visual fatigue: Because of general fatigue and brain fog, your eyes may feel more tired or strained when reading or using screens.
Less Common Eye Issues
- Myxedema (severe untreated hypothyroidism) can cause swelling around the eyes and even optic nerve problems, but this is rare.
If you're experiencing persistent eye strain or blurry vision and have hypothyroidism, it's worth checking:
- If your thyroid hormone levels are well controlled
- If you also have dry eyes or another eye condition
- Whether any medications (like gabapentin, which I'm taking for a chronic cough) might be adding to the issue
I’m not sure if my eye issues are directly related to hypothyroidism, but I didn’t start having problems until after my RAI therapy, when I turned hypo. I had already been taking gabapentin before that, so I don’t think that’s the cause but I honestly don’t know? Since turning hypo, my eyes have felt tired, gritty, and blurry - even after getting them checked and being told nothing had changed from my last exam. I wear glasses and readers, but my vision still feels off and right now I’m not seeing clearly.
Can You Manage Hypothyroidism Naturally?
While medication is usually required to manage hypothyroidism effectively, supportive natural approaches can complement medical treatments, enhance well-being, and help you feel your best. These can be discussed with your doctor.
Diet and Nutrition
Eating foods rich in nutrients beneficial to thyroid health can support your overall wellness:
- Iodine-rich foods (seaweed, eggs, fish, dairy products)
- Selenium-rich foods (Brazil nuts, sunflower seeds, lean meats, fish)
- Foods high in zinc (nuts, legumes, pumpkin seeds, whole grains)
- Anti-inflammatory foods (berries, turmeric, ginger, leafy greens, healthy fats like avocados and olive oil)
Reducing processed foods, refined sugars, and gluten may also help, as these can negatively affect thyroid health for some individuals.
Lifestyle and Self-care
Simple daily habits can significantly support thyroid function:
- Stay active with gentle, consistent exercise to boost metabolism and mood.
- Manage stress through yoga, meditation, or deep breathing exercises, all beneficial to hormone balance.
- Prioritize restful sleep to naturally regulate hormones and replenish your energy.
- Time your medication properly: Take your thyroid medication first thing in the morning, on an empty stomach, with water only. Avoid food, coffee, or supplements for 45 to 60 minutes. I keep my prescription on my bedside table and when I get up around 5am to pee, I take my pill then.
- Be mindful of supplement timing: Iron, calcium, magnesium, and multivitamins can interfere with how well thyroid medication is absorbed. Wait at least 4 hours after taking your thyroid pill before taking these supplements. I take a lot of supplements and this is one reason I now take my levoxyl when I get up to pee.
Herbal and Home Remedies
Many find herbal remedies beneficial (always discuss these with your healthcare provider first):
- Ashwagandha: An adaptogenic herb from Ayurvedic medicine that may help balance thyroid function.
- Bladderwrack (seaweed): Rich in iodine, potentially aiding hormone production - use with care, as excess iodine can be harmful.
- Ginger tea: Helps reduce inflammation and gently boosts energy levels.
Homeopathic Remedies
Homeopathy is another supportive approach, frequently used alongside traditional treatments. Remedies include:
- Calcarea Carbonica: For sluggishness, fatigue, cold sensitivity, and weight gain.
- Sepia: For thyroid-related menstrual issues, fatigue, or mood swings.
- Graphites: Recommended for sluggish digestion, dry skin, and thyroid-related weight gain.
Always consult a qualified homeopath before starting homeopathic treatment.
Complications If Hypothyroidism Goes Untreated
Ignoring hypothyroidism symptoms or delaying treatment can lead to significant health issues:
- Heart problems: Elevated cholesterol, slow heart rate, or heart failure.
- Mental health issues: Depression, anxiety, cognitive impairment, or memory loss.
- Infertility or pregnancy complications: Irregular menstrual cycles or increased risks during pregnancy.
- Peripheral neuropathy: Pain, numbness, or tingling in your hands and feet.
- Goiter: Enlargement of the thyroid gland causing neck discomfort or difficulty swallowing.
- Myxedema: A rare but potentially life-threatening condition marked by extreme fatigue, low body temperature, and confusion or coma.
Fortunately, these complications are typically preventable with early diagnosis and proper medical management.
When to See a Doctor
If you're experiencing symptoms of hypothyroidism - especially after radioactive iodine treatment - reach out to your doctor promptly. Simple blood tests can quickly determine if your thyroid is functioning correctly. Your healthcare provider will help you choose the most effective course of action, which often includes medication, lifestyle changes, and supportive treatments.
If you’re doing all the right things - taking your medication, eating well, staying active - but still feeling off, believe me, you’re not alone - it might be time to talk to your doctor about:
- Optimizing your Free T3 and Free T4 levels, not just aiming for "normal"
- Checking Reverse T3 and other key nutrients
- Reviewing whether your current dose or timing of medication is ideal for you
- Exploring a T4/T3 combination therapy if you’re not responding well to Levothyroxine Sodium alone
Having hypothyroidism doesn't mean you can't feel vibrant, energized, and healthy again. Whether your hypothyroidism developed naturally or following RAI therapy, being proactive and informed about your health empowers you to thrive. Listen to your body, trust your instincts, and don’t hesitate to seek support.
Related Articles
NIH - How Biotin Induces Misleading Results in Thyroid Bioassays
American Thyroid Association - Thyroid Function Tests and Biotin
