The Thyroids Role in Weight Loss … and Weight Gain!

99.99% of the time people do not think about their thyroid. I bet if I did a random poll, most people wouldn’t even know what it was or what it did! But when it goes array, our waist line sees it and we start to pay attention.

The thyroid is a small gland in our neck that releases hormones into our body. Most of the time it goes unnoticed and underappreciated. The reason why the thyroid gets linked to our waistline is because the hormones it releases affect our metabolic rate, or how many calories we burn. The higher our metabolic rate is, the more calories we burn in a given day and therefore the easier it is to keep our weight under control.

The thyroid releases two hormones, T3 and T4. Issues with the thyroid are generally classified two ways.

Hyper-thyroidism: Too much thyroid hormones
Hypo-thyroidism: Too little thyroid hormones.

The relationship with your weight put simplistically looks something like this…

Too much thyroid hormones = Metabolism goes up = Weight loss
Too little thyroid hormones = Metabolism goes down = Weight gain

Now this is a very simple relationship of a very complex hormone system but that is the generalizable take away. Hypothyroidism is more common that hyper, affecting as many as 10 million Americans (I’m not sure of the Canadians stats) so we will be focusing on hypothyroidism.

The Chicken or the Egg?

Now many people believe that it was their hypothyroidism that led to their weight gain … and this can be true! But the relationship isn’t one sided. Being overweight can cause you to have issues with your thyroid AND having issues with your thyroid can cause you to become overweight. One can feed on the other.

That being said, if you are experiencing a sudden weight gain with no changes in your activity level or food consumption, your thyroid may be the culprit. A simple blood test can figure out your thyroid levels and see if there is an issue.

Add Stress into the Mix

Another piece of the weight gain puzzle may be your stress levels. High stress can act very similarly to a low thyroid in that it can drop your metabolism and lead to weight gain. It also acts on the thyroid and brings your hormone levels down. Working on stress management techniques which could be exercise, walking, meditation, time with family or other ways will work to improve your thyroid levels.

Working with your doctor to get your thyroid levels up to where they should be, is going to be an important part of the process if you are trying to lose weight. Medications are available that help give your thyroid the boost it needs!

A low thyroid level doesn’t make weight loss impossible! It is important to realize that the loss will likely be slightly slower and to take that into consideration when you are mapping our your weight loss goals.


Pearce, E. N. (2012). Thyroid hormone and obesity. Current Opinion in Endocrinology, Diabetes, and Obesity, 19(5), 408-413. doi:10.1097/MED.0b013e328355cd6c [doi]

Sanyal, D., & Raychaudhuri, M. (2016). Hypothyroidism and obesity: An intriguing link. Indian Journal of Endocrinology and Metabolism, 20(4), 554-557. doi:10.4103/2230-8210.183454 [doi]

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Christina Prevett

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