Let’s talk about one of the most frustrating challenges anyone can face: trying to lose weight when your thyroid isn’t playing ball. You’ve been eating healthier, trying to move more, and still, the scales don’t budge. Sound familiar? You’re not alone.
Thyroid issues, especially hypothyroidism, can feel like a constant uphill battle when it comes to weight loss. And it’s not just about the numbers on the scale—low thyroid function can leave you feeling tired, sluggish, and often mentally drained, which makes it even harder to stay motivated.
I’ve seen clients struggle with this firsthand, feeling like they’re doing everything right but getting nowhere. The reality is, hypothyroidism isn’t just a bump in the road—it’s like driving with the brakes on. But here’s the good news: while a low thyroid can slow your metabolism, it doesn’t make weight loss impossible. It just means we need to get a little more strategic and a lot more patient.
In this article, we’re going to dive into what’s really going on when you have an underactive thyroid, why typical weight loss advice doesn’t always apply, and what you can do to start seeing real results. So let’s get into it.
What’s Going On with Your Thyroid (And Why It Affects Your Weight)
First, a quick science lesson. Your thyroid is a small, butterfly-shaped gland in your neck that plays a big role in regulating your metabolism—the process your body uses to convert food into energy. When your thyroid is underactive (hypothyroidism), it doesn’t produce enough of the hormones that keep your metabolism running efficiently. This can lead to a whole host of symptoms, including fatigue, weight gain, and feeling cold all the time, among others.
The relationship between your thyroid and your weight isn’t just about calories in and calories out. It’s also about how your body uses those calories. When your thyroid function is low, your metabolism slows down, meaning you burn fewer calories even at rest. You might also experience water retention, which can make you feel bloated and heavier than you actually are.
But it’s not just your metabolism that’s affected—low thyroid function can also mess with your energy levels, mood, and even your digestion, all of which can indirectly affect your ability to lose weight. It’s a perfect storm of physiological and psychological barriers that make the weight loss journey feel like running through treacle.
The Mistakes Most People Make When Trying to Lose Weight with Low Thyroid
- Relying on Calorie Cutting Alone
The classic approach to weight loss—eat less, move more—doesn’t always work if you have a low thyroid. Severely cutting calories can backfire, causing your metabolism to slow even further and making it harder to lose weight. Plus, it can lead to muscle loss, which further reduces your metabolic rate. This can create a cycle of restriction, fatigue, and frustration. - Overdoing Cardio
When it feels like your metabolism is working against you, it’s tempting to try to outrun the problem with endless cardio sessions. But this can lead to burnout, increased stress hormones, and potential muscle loss. For those with thyroid issues, it’s more about finding a balance that supports your body without pushing it too hard. - Neglecting Strength Training
Building muscle is one of the most effective ways to boost your metabolism, especially if you have a low thyroid. Unfortunately, many people overlook strength training, thinking it won’t help with weight loss. But muscle tissue burns more calories than fat, even at rest, making it a crucial part of a sustainable weight loss strategy. - Skipping Medications or Not Managing Them Properly
Managing hypothyroidism effectively often requires medication. But if you’re not taking your medication consistently, or if your dosage isn’t right, it can seriously impact your progress. Regular check-ins with your doctor to ensure your thyroid levels are where they should be can make all the difference. - Ignoring Your Nutrition Beyond Just Calories
What you eat matters just as much as how much you eat. With thyroid issues, it’s not just about calories; it’s about nutrients that support your thyroid function and overall health. Without the right balance of proteins, fats, carbs, and essential vitamins, your body won’t be primed for optimal weight loss.
The Science: Why a Low Thyroid Slows Weight Loss and What You Can Do About It
Studies have shown that hypothyroidism is associated with a lower basal metabolic rate, meaning your body burns fewer calories at rest compared to someone with normal thyroid function (Kong et al., 2016). This doesn’t mean weight loss is impossible—it just means you need a different approach.
Research indicates that resistance training (like weight lifting) can help counteract the drop in metabolism caused by hypothyroidism by preserving and building muscle mass (Villareal et al., 2017). Additionally, balanced nutrition that includes sufficient protein helps support muscle maintenance and can help keep you feeling full longer, making it easier to stick to your eating plan.
There’s also evidence that managing stress and getting adequate sleep can positively impact thyroid function and, by extension, weight management (Chaker et al., 2017). Since stress hormones like cortisol can interfere with thyroid function and promote weight gain, incorporating stress-reducing activities such as yoga, meditation, or simple deep breathing exercises can be beneficial.
Practical Steps to Lose Weight with a Low Thyroid
So, what can you do if you have hypothyroidism and want to lose weight? Here are some strategies that work—and they’re backed by science, not quick-fix nonsense.
- Optimise Your Medication and Medical Support
This is the foundation. Make sure you’re taking your thyroid medication exactly as prescribed, and keep up with regular blood tests to monitor your levels. If something feels off, don’t hesitate to talk to your doctor—sometimes dosages need to be adjusted over time. - Prioritise Protein in Every Meal
Protein is your best friend when it comes to managing a low thyroid. It helps keep you full, supports muscle maintenance, and has a higher thermic effect than carbs or fats, meaning your body burns more calories digesting it (Paddon-Jones et al., 2008). Aim to include a source of protein with every meal, whether it’s lean meats, fish, eggs, beans, or plant-based options like tofu and lentils. - Incorporate Strength Training Twice a Week
You don’t need to lift like a bodybuilder, but some form of resistance training is crucial. Start with bodyweight exercises like squats, lunges, and push-ups, or use light weights if you’re new to strength training. The goal is to build muscle, which can help counteract the metabolic slowdown of hypothyroidism. - Focus on Fibre for Fullness
Fibre-rich foods like vegetables, fruits, whole grains, and legumes not only help with digestion (which can be sluggish with hypothyroidism) but also keep you full longer. This can help you naturally reduce calorie intake without feeling deprived. - Manage Stress and Prioritise Sleep
Stress and poor sleep are known to affect thyroid function and weight regulation. Make it a habit to wind down before bed with calming activities, aim for at least 7-8 hours of quality sleep, and incorporate stress management techniques like yoga, journaling, or even just a quiet walk in nature. - Stay Hydrated, but Be Cautious with Goitrogens
While staying hydrated is essential for metabolism, it’s also worth noting that certain foods (like raw kale, broccoli, and cauliflower) contain goitrogens that can interfere with thyroid function when consumed in large quantities. You don’t need to avoid them completely, but cooking these vegetables can reduce their goitrogenic effect, making them safer for thyroid health. - Track, But Don’t Obsess
Tracking food intake can be helpful for identifying patterns and staying mindful, but it’s not about perfection. Use it as a tool to understand your eating habits, not as a way to micromanage every bite. The goal is to find a rhythm that feels sustainable and doesn’t add stress to your life.
What I Learned: Finding a New Normal with Hypothyroidism
Getting to a place where you feel comfortable in your own skin while managing hypothyroidism takes time, patience, and a whole lot of self-compassion. It’s not about quick fixes or punishing yourself into losing weight. It’s about understanding your body, working with it rather than against it, and setting realistic expectations.
I’ve seen clients transform their relationship with food, exercise, and their bodies by shifting their mindset from “I have to lose weight” to “I’m learning to care for myself.” That change in perspective makes all the difference.
Remember, progress isn’t just measured by the scale. It’s in the increased energy, the better sleep, the moments of joy you find in movement, and the confidence that grows when you know you’re doing what’s best for your health. Your thyroid might slow you down, but it doesn’t define you or your ability to make positive changes.
Your Path Forward: Start Your Journey Today
Ready to tackle your thyroid challenges head-on? If you’re looking for support that understands the unique hurdles of hypothyroidism, I’m here to help. I’m offering two weeks of free coaching to help you jumpstart your journey. Together, we’ll create a personalised plan that fits your lifestyle, supports your thyroid health, and helps you lose weight in a sustainable way.
Let’s rewrite the story of what’s possible with a low thyroid—because you deserve to feel your best, inside and out.
References:
- Chaker, L., Bianco, A. C., Jonklaas, J., & Peeters, R. P. (2017). Hypothyroidism. The Lancet, 390(10101), 1550-1562.
- Kong, W., Zhang, H., Song, J., Zhang, J., Hu, C., & Ren, Z. (2016). Thyroid hormones and basal metabolic rate in patients with hypothyroidism. Journal of Clinical Endocrinology & Metabolism, 101(4), 1505-1510.
- Paddon-Jones, D., Westman, E., Mattes, R. D., Wolfe, R. R., Astrup, A., & Westerterp-Plantenga, M. (2008). Protein, weight management, and satiety. The American Journal of Clinical Nutrition, 87(5), 1558S-1561S.
- Villareal, D. T., Smith, G. I., Shah, K., Mittendorfer, B., & Schechtman, K. B. (2017). Weight loss, exercise, or both and physical function in obese older adults. New England Journal of Medicine, 376(20), 1943-1955.
Let’s make those changes together—one step at a time!