Low Carb Diets & Your Metabolism/Thyroid

There is a huge amount of often conflicting information available when it comes to how best to look after ourselves in terms of getting the right kind of exercise and nutrition. In this article Holistic Nutritionalist and Wellness Expert Natalie Brady explains in simple terms how weight loss strategies such as low carb diets can affect thyroid functioning and be harmful in the long run if you’re not getting the right balance of carbs, protein and healthy fats for your individual needs.

Natalie also shares her recommendations for food sources when choosing healthy carbs as well as advice on what tests to ask your doctor for if you want an accurate measure of how your whole thyroid is functioning.

Could A Low Carb Diet Be Affecting Your Thyroid Health & Metabolism?

Carbs are not the devil my friends! Carbohydrates are needed for T3 thyroid hormone production! So remember it’s not about having zero carbs in your diet. Yes, research has proven low carb diets are effective at fat loss, but it’s about getting the balance right for YOUR individual body and your exercise levels.

If you’ve been following me for a while you’ll know I am actually a fan of moderate to slightly lower carb intake, when done correctly with moderate-higher protein, moderate fat and an abundance of non starchy fibre rich veggies. Eating this way is also very supportive of more stable blood sugar balance. And when blood sugar is balanced, your body becomes more effective at burning fat.

However, a typical picture I see all the time in clinic is women lowering carbs, increasing exercise, fasting, skipping meals or restricting calories to lose weight for a long period of time. This may work in the short term, but can be harmful in the long run and could even backfire and cause weight plateau or weight gain. It can cause additional stress to the body causing higher cortisol levels which affects thyroid health and prevents your body from burning fat along with causing other hormonal issues.

Long term calorie restriction, fasting or long term low carb diets for some women can mean you are not producing enough of the T3 hormone. This will mean you might find it harder to keep your weight stable or you might struggle with low energy. It’s about getting the balance right. Carbs are still important for our health, particularly if you exercise a lot, and do lots of HIIT.

Thyroid hormones are well known to affect muscle protein synthesis. So low thyroid function could cause a decrease in muscle mass, this makes it a lot harder to build muscle (which is important for weight loss). If you decide to follow a lower carb diet make sure you’re not restricting calories too much (especially if you’re exercising more) and make up for it in other areas by consuming adequate protein and healthy fats. Our body’s still need fuel and enough calories to function optimally. You can always check in with a nutritionist to help you get the balance right and create a personalized plan for you.

When choosing carbs go for wholefood sources, my personal favourites are sweet potato, regular potatoes, pumpkin, quinoa, brown rice, basmati rice, buckwheat, oats and fruit.

When it comes to looking at your thyroid hormones you can go to your doctor and ask to check T3, T4, TSH and thyroid antibodies. Often doctors here in New Zealand only check TSH, however this test alone is not an accurate measure of how your whole thyroid is functioning, you need to take a wider look and look at your whole thyroid picture. When you get your results you can discuss these results with your nutritionist who can assess your results and see if you’re within the ‘optimal health’ range, not just the ‘average health’ range. From there we can help you make specific diet and lifestyle recommendations based on your results if they are low or high.

Natalie is a Registered Clinical Nutritionist, health influencer, blog writer & recipe creator. She believes in a wholefoods approach to good health, focusing on simple strategies for modern, busy people. If you feel you need more support or a personalised lifestyle and nutrition plan to help you get your health on track you can get in touch with Natalie here. She offers consultations via Skype if you are unable to meet in person.