8 Ways Eating Disorders Affect The Menstrual Cycle, Hormones, Infertility, And Pregnancy

Women who live with anorexia nervosa or bulimia nervosa experience profound disruptions in their hormonal health. Here are eight of the most important concerns for endocrine health for women who live with these eating disorders.

When weight falls below 85 percent of normal, menstruation usually stops

Reduced body weight is closely linked to amenorrhea. Regaining body weight to 90 percent of normal usually restores menstruation —but scientists don’t really know why. In some women, it’s not enough to regain body weight. It’s also necessary to regain body fat. In other women, it seems that the body’s ability to produce estrogen and progesterone, luteinizing hormone and follicle stimulating hormone, all of which power the period, somehow atrophies. About 14 percent of women who recover from their eating disorder do not restart their periods. Of course, when women don’t have periods, they don’t get pregnant.

Estrogen replacement therapy or going on the pill can lift anxiety and depression

Many women who suffer anorexia or bulimia also have to deal with crippling anxiety and depression. For women who live with these eating disorders, estrogen replacement therapy or taking high-estrogen contraception relieves anxiety, depression, or both.

Oxytocin levels after a meal are predictive of the severity of anorexia

Oxytocin is a bonding hormone. A woman’s body secretes it after giving birth to make it easier to bond with the baby. Women’s bodies release oxytocin in the presence of family and friends. High levels of oxytocin after a reduced meal, however, predict severe difficulties in managing an eating disorder.

The severity of an eating disorder has more to do with hormone levels than with weight

Two hormones levels can predict how difficult it will be to recover from anorexia or bulimia. One of these hormones is the stress hormone cortisol. The higher the cortisol level, the more severe the eating disorder, regardless of BMI. The other hormone that predicts the severity of an eating disorder is peptide YY, also known as PYY and peptide tyrosine tyrosine (for the two tyrosine groups in its molecular structure). PYY is a hormone secreted by the digestive system shortly after we begin to eat that tells our brains that we are getting full. In eating disorders, there is a greater release of PYY and the brain gets a stronger message that one has eaten enough.

Teenage girls who have anorexia or bulimia become resistant to growth hormone

Growth hormone is essential for continuing development of bones and muscles into early adulthood. Fasting actually increases the body’s production of growth hormone. Teenage girls produce up to 20 times the normal amount of growth hormone, as their bodies attempt to protect muscles and bones from breaking down. However, the extra growth hormone does not result in extra growth, because there aren’t enough active fat cells to generate another hormone called STAT-5 that activates growth hormone where it’s needed. The growth hormone does protect against hypoglycemia and helps fat cells release fatty acids for energy.

Severe weight loss causes variations in thyroid hormone

When the thyroid does not receive the mineral nutrients it needs to make thyroid hormone, the pituitary gland tries to stimulate production anyway by releasing TSH (thyroid stimulating hormone). This form of “hypothyroidism” isn’t really a thyroid problem. It’s a nutrient problem. Levels of active thyroid hormone are low, so the person who is dealing with the eating disorder feels cold and sluggish. Regaining weight usually restores thyroid hormone production.

Women who live with eating disorders often produce too much of an anti-diuretic hormone

Anorectic women and girls often suffer overproduction of a hormone called vasopressin. This hormone binds to the kidneys, so they send more water back into circulation. Fluid levels increase, so the concentrations of sodium and other electrolytes decrease. Low sodium levels can cause seizures without warning. Many antidepressants aggravate this phenomenon. The solution is not to stop the antidepressants. It’s to consume more sodium, under the doctor’s supervision.

Women who live with eating disorders are prone to osteoporosis

Studies have found that up to 86 percent of women who have anorexia or bulimia have decreased bone mineralization at one or more sites in their skeletons. They develop osteoporosis much earlier in life than would otherwise be expected. Sixty percent of teenaged girls who have anorexia have at least one bone fracture. Restoring menstruation helps stop bone mineral loss, but complete recovery of bone health requires several years of recovery from the eating disorder.