Title: The Link Between Thyroid Hormones and Weight
Headings: The Relationship Between Thyroid Hormones, Metabolism, and Weight
The Relationship Between Thyroid Hormones, Metabolism, and Weight
How the Thyroid Gland Works
The Role of Metabolism
The Role of Thyroid Hormones
Research
Hypothyroidism and Weight
Weight Loss With Treatment
The More Medication Myth
Hyperthyroidism and Weight
The Weight Loss Challenge
Low T3 Levels
Hormone Resistance
Leptin Resistance
Insulin Resistance
A Word From Verywell

Content: A lot of this weight is excess water and salt. Typically, the more severe the hypothyroidism, the greater the weight gain, but usually it's between five and 10 pounds. 5 ﻿
Somewhere between 10% and 60% of obese adults also have autoimmune hypothyroidism. 2 ﻿ Some studies have concluded that even mild hypothyroidism can lead to weight changes and may be a risk factor for weight gain and changes in BMI. Verywell / Emily Roberts
Weight Loss With Treatment
There aren't many scientific studies regarding how much weight is gained or lost once hypothyroid people are treated with the synthetic thyroid hormone levothyroxine, but the limited evidence that is available indicates that not everyone loses weight with treatment and in the ones who do, it's limited. Once your hormone levels are within the normal range, you may lose a small amount of weight that mainly consists of the extra water and salt your body has built up. However, weight gain has multiple factors and yours is more than likely not all due to your thyroid's slowdown. One way to tell is if treatment has helped all of your other thyroid symptoms but not your weight. This indicates that your thyroid very likely isn't the only factor behind your gain. The More Medication Myth
You may have heard that thyroid hormones can be used to lose weight, even in people without thyroid disease.