When your thyroid gland does not produce sufficient hormones, you may develop hypothyroidism, also referred to as an underactive thyroid. According to MayoClinic.com, women older than the age of 50 are most at risk for developing hypothyroidism. Joint pain, obesity, heart disease and infertility are common side effects of the disease if left untreated. Water weight gain and bloating, particularly in your face, can indicate early warning signs of an underactive thyroid.
The more severe your hypothyroidism, the more water weight you may gain. The majority of the weight you gain from an underactive thyroid gland is made of water and salt, according to the American Thyroid Association. Excessive weight gain -- more than 10 lbs. -- usually is not due to your thyroid, however. The average water weight you'll gain from an imbalance of thyroid hormones is 5 to 10 lbs. Any other excess pounds you’re carrying are due to overeating.
While fluid retention is one of the most common symptoms of an underactive thyroid, there are other signs you may have the condition. You may have low energy levels, especially after waking up in the morning. Headaches, cold hands or feet, chronic constipation, brittle nails and dry skin are other symptoms related to hypothyroidism. You may have muscle aches and stiff joints, depression and high cholesterol. Women may experience heavier menstrual cycles than normal.
You will lose the excess water weight once you receive thyroid hormones to treat your condition. The most weight you'll lose however is about 10 percent of your total body weight. Any other weight gain you may have undergone is due to your consumption of more calories than you burn, just like people who don't have hypothyroidism. Hypothyroidism is a condition that develops slowly over a period of time, long after you've established your poor eating habits. According to the American Thyroid Association, if you are obese, you may not experience any significant weight loss after you receive treatment.
Thyroid medications may be used to lose excess water weight even if you don’t have hypothyroidism. The practice is dangerous, however, and can cause additional complications, such as metabolic disorders. According to the American Thyroid Association, while thyroid hormones may increase the amount of weight you lose more so than just by dieting, the water weight usually returns when you stop using the supplements.