Hypothyroidism, Metformin & Weight Loss

Metformin, sold under the brand name Glucophage, is a diabetes drug that can improve insulin sensitivity and promote weight loss by helping lower glucose levels and prevent hunger. It works as a weight-loss aid, but may not be suitable for people with hypothyroidism because it can interact with levothyroxine -- thyroid replacement hormone -- and lead to high blood sugars.


Your thyroid gland is located at the base of your throat, in front of your vocal chords. Part of your endocrine system, your thyroid produces T4 and T3 hormones which control the speed your body uses oxygen and energy -- your metabolism. Low thyroid function results in a slower metabolism; one of the first signs of hypothyroidism is weight gain. Other symptoms include brittle or weak nails and hair, fatigue and a sensitivity to cold. Hypothyroidism is treated with supplemental thyroid hormone; which your body can also convert to T3 hormone. Rarely do you need to supplement both hormones. Levothyroxine is the most common treatment and replaces T4 hormone, boosting metabolism

Weight Loss and Hypothyroidism

Weight Loss and Synthroid

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Until your hypothyroidism is controlled and your metabolic function returns to normal, it will be difficult for you to lose weight. It can take three months or longer to find the correct dose of levothyroxine and buildup enough thyroid hormone in your body. You can try to boost your metabolism by changing your body composition and increasing muscle mass. The more muscle tissue you have in comparison to fat, the higher your metabolism will be -- and the more calories you will burn, even at rest. Weight loss requires you to burn more calories than your consume, so that your body will break down stored fat to use for energy.

Metformin and Levothyroxine

Metformin decreases the amount of glucose your body can absorb from the food you eat while simultaneously increasing the sensitivity of your cells to insulin. Metformin is only used by Type 2 diabetics; those with Type 1 diabetes do not produce insulin and can not control the amount of glucose in their bloodstream. Levothyroxine can affect blood sugar and cause hyperglycemia -- elevated glucose levels. People with diabetes must pay close attention to glucose levels when using levothyroxine. Because levothyroxine can affect metformin and make it less effective, these two drugs should not be used together.

Healthy Weight Loss

L-Carnitine & Hypothyroidism

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Losing weight with both diabetes and hypothyroidism can be challenging. A combination of a healthy, calorie-reduced diet and exercise should help you lose weight at a slow and steady pace -- about 1 to 2 pounds per week. Work with your doctor and dietitian to find an eating plan that can help control your diabetes and support your thyroid health. It takes a calorie-deficit of 3,500 calories to lose 1 pound of body fat -- reducing your current caloric consumption by 500 calories daily should result in losing 1 pound a week.