When leptin was first identified in the mid-1990s, scientists thought its greatest contribution would be to help people lose weight. That’s because the hormone is highly involved in regulating your body weight. But after more research, leptin was discovered to play a role in other body functions, including ovulation, menstruation and reproduction. If recent research is confirmed, your doctor may be able to one day treat your lack of a period with synthetic leptin.
Leptin is a protein hormone that is released from your fat cells while you sleep. It became known as the “satisfaction” hormone because the substance binds with receptors in your brain and makes you push the plate away, signaling that you’ve had enough. It’s one of many substances in your body that play a role in body weight. Leptin, however, proved far more complex than previously understood, according to a 2009 article published by the "LA Times." In subsequent research, scientists learned it also plays a role in other biological processes, including immune function and reproduction.
Amenorrhea refers to the absence of a woman’s menstrual cycle, or to missing at least three consecutive periods. Young women who reach age 16 without having a period are also considered to have amenorrhea. Pregnancy, breast-feeding and menopause are natural causes of the condition, but birth control and other medications can also cause it. MayoClinic.com reports that lifestyle issues such as excessive stress as well as health issues such as hormonal imbalances can also cause amenorrhea.
Low Body Fat and Menstrual Cycles
Having excessively low body weight can interfere with the development and functioning of your hormones. Low body weight can stop you from ovulating altogether. Women who are professional athletes or dancers, exercise too much or have eating disorders often experience amenorrhea. according to MayoClinic.com. That’s because they tend to lose more body fat and use more energy than they consume. As a consequence, they tend to have low levels of estrogen and abnormal thyroid hormone levels. A common thread among these women is an energy deficiency, according to a 2004 study published in the “New England Journal of Medicine.” They studied a group of women suffering hypothalamic amenorrhea due to their low body weight or over-exercising. In addition to leading to infertility, this form of amenorrhea can lead to osteoporosis.
Leptin Can Restore Periods
Energy deficiencies also lead to hypoleptinemia, or low levels of leptin, according to 2011 Harvard research published in the “Proceedings of the National Academy of Sciences of the United States.” Researchers demonstrated that leptin plays a role in the development of amenorrhea. In addition, they found that replacing the hormone and bringing participants’ leptin levels to normal “may prove to be a safe and effective therapy for women with” hypothalamic amenorrhea.
How It Works
In animal studies, leptin administration increased luteinizing hormone, which is secreted by the pituitary glands. In women, luteinizing hormone also causes ovulation. Leptin also increases the weight of the uterus. Leptin levels rise and fall by a predictable pattern during the menstrual cycle of most healthy women, peaking at mid-cycle when luteinizing hormone is released, says MedlinePlus. Scientists don’t fully understand why leptin levels are highest at this stage of the menstrual cycle, but they suspect that another reproductive hormone, progesterone, stimulates the release of leptin from fat cells after it has been primed by estrogen. In any case, it appears a dangerous shift in your energy levels — by how much you eat and how many calories you burn — presents a cascading set of results that can ultimately result in missing your periods.
- Harvard Gazette"; Obesity: Reviving the Promise of Leptin; Nancy Fliesler; Jan. 6, 2009
- "Los Angeles Times"; The Waning Promise of Leptin in the Obesity Fight; Elena Conis; Aug. 9, 2010
- "New England Journal of Medicine"; Recombinant Human Leptin in Women with Hypothalamic Amenorrhea; Corrine K. Welt et al.; Sept. 2, 2004
- “Proceedings of the National Academy of Sciences of the United States"; Leptin Is an Effective Treatment for Hypothalamic Amenorrhea; Sharon H. Chou et al.; April 19, 2011
- "Human Reproduction Update"; Leptin in Human Reproduction; Ioannis Messinis and Sypros Milingos; 1999