Hormones play a major role in energy usage and storage, metabolism, growth, and fat distribution. When hormone levels shift, unexpected weight gain may occur. Excessive weight gain can increase your risk of weight-related conditions. It’s important to discuss any noticeable weight changes with a healthcare provider and treat underlying conditions.
Besides your diet and physical activity, a group of hormones work together to influence your body weight. Here’s what to know about some of these key hormones.
Estrogen
Estrogen is a female sex hormone that the ovaries primarily secrete. It plays a key role in menstruation and also helps regulate body fat, metabolism, and fat distribution. Decreasing levels of estrogen can result in weight gain, particularly around your abdominal (belly) region.
Insulin
Produced in your pancreas, insulin helps keep your blood sugar in a healthy range. Sometimes, people don’t respond well to the insulin their body produces, a condition called insulin resistance. As a result, the body produces more insulin.
Diabetes occurs either when your body can’t use the insulin it produces (type 2 diabetes) or when your body doesn’t produce insulin at all (type 1 diabetes).
Leptin
Leptin is a hormone that helps maintain your body weight and sends signals to your brain that you are full after eating. Fat cells called adipocytes secrete this hormone.
Because fat cells release this hormone, people who are overweight or obese often have higher leptin levels, but they may not respond well to it.
Cortisol
Cortisol is known as the stress hormone. Your adrenal glands near your kidneys produce this hormone in response to stress. It’s normal for cortisol to increase during acute (short-term) stress. Chronic (long-term) high cortisol levels can lead to inflammation, metabolic changes, muscle weakness, and weight gain.
Ghrelin
Ghrelin is produced mainly by your stomach. Its role is to tell your brain that you’re hungry before meals, increase your food consumption, and regulate your fat storage. Typically, weight gain is associated with lower ghrelin levels.
Several conditions and circumstances may contribute to hormonal weight gain.
Menopause
Menopause is defined as the time when you’ve stopped having periods for 12 months in a row, but the time leading up to menopause (perimenopause) can last several years. People in menopause and perimenopause experience drops in their estrogen levels.
Besides symptoms like irregular periods, mood changes, sleep disturbances, and hot flashes or night sweats, many people notice weight gain and changes in metabolism.
Low Testosterone
People assigned male at birth may naturally experience a gradual drop in testosterone (a male sex hormone) starting in their 30s or 40s. At times, low testosterone can be caused by side effects from medications, injuries to the testicles, testicular cancer, and hypothyroidism (underactive thyroid).
Low testosterone is associated with decreased metabolism and weight gain.
Polycystic Ovarian Syndrome
Polycystic ovarian syndrome (PCOS) is a condition characterized by higher-than-normal levels of androgens (masculinizing hormones, including testosterone) among people assigned female at birth. It’s also characterized by problems with ovulation. Symptoms include increased facial hair, irregular periods, and unwanted weight gain.
People with PCOS also often experience metabolic conditions like insulin resistance, which can contribute to weight gain.
Hypothyroidism
Hypothyroidism is when you produce too little thyroid hormone. This can lead to symptoms like fatigue, weakness, joint pain, thinning hair, depression, irregular periods, and weight gain.
Insulin Resistance
When you have insulin resistance, your body can’t respond properly to the insulin your pancreas secretes. This can cause the glucose (sugar) circulating in your body to build up.
Insulin resistance is thought to be caused by excess weight gain in the abdominal area. It can also make it difficult to lose weight, and it can lead to unintentional weight gain.
Unchecked insulin resistance can lead to type 2 diabetes.
Insomnia
Having trouble falling and staying asleep can lead to weight gain. Researchers are still trying to understand why, but one theory suggests that sleep deprivation alters chemical signals that can impact appetite and the brain’s motivation and reward system.
Symptoms of hormonal weight gain depend partly on which hormones are involved and what condition is causing the hormonal imbalance.
For instance, if perimenopause or menopause is causing weight gain, you may also experience hot flashes and irregular periods. If hypothyroidism is causing weight gain, you may also experience fatigue, weakness, depression, and joint issues.
Hormonal weight gain also tends to occur in the abdominal area rather than other areas of the body.
If you experience weight gain that you think may be related to hormones, consider visiting your healthcare provider.
They will likely do a physical examination and discuss your health history, diet, lifestyle, and any other symptoms you have besides weight gain. They may also ask about the medications you take, if any, as some can lead to weight gain.
A healthcare provider may order blood tests to help them determine whether a medical condition involving hormones is causing your weight gain.
Stopping hormonal weight gain may involve any of these strategies:
Addressing the underlying cause: Treating weight gain may involve treating the underlying cause. For instance, if you have hypothyroidism, taking thyroid medication to rebalance your hormones may help you lose the weight you’ve gained. Hormone replacement therapy may help with conditions like menopause and low testosterone.
Lifestyle choices: It may also help to make balanced diet choices, increase your exercise, get enough sleep, and manage stress. Your healthcare provider can let you know whether specific diets may work best for your hormone needs and whether other lifestyle strategies could help.
Medication or surgery: A healthcare provider may sometimes recommend medication or surgery to treat hormonal weight gain. For example, GLP-1 weight loss medications may help people who live with conditions such as diabetes or insulin resistance lose weight. Surgeries like gastric bypass may be appropriate for some people with hormonal weight gain.
There are many potential causes of weight gain, including hormonal changes and imbalances related to perimenopause, PCOS, hypothyroidism, or insulin resistance.
If you think that you have hormone-related weight gain, talk to a healthcare provider. They can take your history, do a physical exam, and test for possible hormonal causes of weight gain as needed. They can also discuss possible management strategies.