Endometriosis is a common condition where tissue similar to the lining inside the uterus, known as the endometrium, grows outside the uterus, typically on other pelvic organs. This misplaced tissue responds to monthly hormonal cycles, leading to inflammation, scar tissue, and severe pain. Many people with this condition experience confusing and often contradictory changes in body weight and composition. The relationship between endometriosis and body weight is multifaceted, involving both the symptoms of the disease itself and the effects of medical management. Understanding these separate influences helps explain why some individuals report weight loss, while the more common outcome is weight gain or frustrating fluctuations.
Endometriosis and Appetite Changes
While the disease itself does not typically cause sustained weight loss, the intensity of its symptoms can certainly lead to a temporary reduction in body mass. Severe, persistent pain is a hallmark of endometriosis, and chronic pain is known to suppress hunger signals in the body. When pain is debilitating, the resulting psychological and physical stress can make eating unappealing, reducing caloric intake.
Gastrointestinal symptoms frequently associated with endometriosis also contribute to decreased appetite. Endometriotic growths on the bowel can cause severe nausea, vomiting, or alternating bouts of diarrhea and constipation. These digestive disturbances disrupt normal eating patterns, making it challenging to consume adequate nutrition. For individuals experiencing severe disease flares, this combination can result in unintentional weight loss, which is a consequence of reduced food intake, not a direct metabolic effect of the disease itself.
Understanding Chronic Inflammation and Weight
The systemic nature of endometriosis means that it drives chronic inflammation throughout the body, significantly impacting metabolic health. Inflammatory cytokines released by the lesions disrupt signaling pathways that regulate glucose use and fat storage. This metabolic disturbance can contribute to the development of insulin resistance, making it more difficult for the body to process sugars effectively and promoting fat accumulation.
Pain-related physical inactivity is a major factor promoting weight gain in people with endometriosis. Debilitating pain often prevents regular exercise, leading to a significant reduction in daily energy expenditure. This lack of movement, combined with chronic fatigue, creates an environment where a caloric surplus and subsequent weight gain are likely over time.
The continuous experience of severe pain triggers the body’s natural stress response, resulting in elevated levels of the hormone cortisol. High cortisol levels are strongly associated with changes in fat distribution, specifically promoting the storage of fat around the abdominal area, known as visceral fat. While the characteristic abdominal swelling, often referred to as “endo belly,” is primarily caused by inflammation and fluid retention, these hormonal changes contribute to true fat gain in the midsection.
How Treatment Affects Body Weight
Medical management of endometriosis frequently involves hormonal therapies that can influence body weight independent of the disease’s intrinsic effects. Combined oral contraceptives and progestin-only treatments, such as dienogest or norethindrone, are commonly prescribed to suppress lesion growth. These hormonal medications can increase appetite in some users and may cause fluid retention, which is perceived as weight gain due to fluctuations on the scale and tighter clothing.
Gonadotropin-releasing hormone (GnRH) agonists and antagonists induce a temporary, reversible menopausal state by significantly lowering estrogen levels. While suppressing lesion growth, this hypoestrogenic state slows the body’s metabolic rate, promoting fat storage and making weight loss challenging. Weight gain is a reported consequence of GnRH analogs, particularly the agonists, which are also associated with side effects such as hot flashes and mood changes.
If treatment involves surgery to remove implants, temporary weight changes may occur during recovery due to reduced mobility and postsurgical fluid retention. If a hysterectomy and removal of the ovaries are performed, the resulting surgical menopause further decreases estrogen. This slows metabolism, leading to a shift in body composition and weight gain over the long term.