Polycystic Ovary Syndrome
How Obesity Can Increase the Chances of Polycystic Ovary Syndrome
The endocrine system, a complex web of glands that secrete various hormones into the body, is an extremely complicated network that can become destabilized in many ways which are largely still not understood. What is understood though, that obesity, that is an excess amount of adipose tissue (body-fat), plays a significant role in all of these disorders and is definitely associated with polycystic ovary syndrome. Otherwise known as PCOS, polycystic ovary syndrome is one of the most common endocrine disorders in females, which affects some 5-10% of women who are of reproductive age and is also responsible for most causes of female subfertility. (1) PCOS has many visible and principal features, but the main ones are obesity, anovulation (which results in irregular menstruation), (2) amenorrhea (absence of a menstrual period) (3) as well as acne (resulting from hormone imbalances in the body). (4)
PCOS is characterized by a number of symptoms, but it is named after the appearance of the ovaries in most women who have the disorder - they are enlarged and contain small cysts along the outer edge of each ovary. (5) Infrequency in menstrual periods, excess hair growth, acne and obesity can all take place in women who develop polycystic ovary syndrome. Difficulties in conception and sudden weight gain can also be indicators of the condition (6) If PCOS is diagnosed early on, treatment can be undertaken immediately and the risks of life-threatening complications such as type 2 diabetes, heart disease and stroke can be reduced significantly. (7)
Obesity and PCOS in general
Obesity has been observed in roughly 50% of the women suffering from polycystic ovary syndrome. (8) It was also observed that many conditions of the metabolic syndrome are also present in women who suffer from PCOS. (9) There are a number of factors that need to be taken into consideration in order to understand how obesity can have an effect on the development of PCOS.
The first of these factors is adipose tissue itself. When a person has far more body-fat than they need, then the conditions that can lead to disorders in the metabolism and endocrine system can develop through excessive release from adipose tissue of a hormone known as leptin, which is responsible for regulating appetite. (10) The normal function of leptin is to control and regulate appetite, but this function can be compromised if there is too much leptin in the body. This condition is known as leptin resistance. (11) Leptin resistance has a pretty obvious consequence, because the body can no longer regulate appetite effectively, the overweight person does not know when to stop eating food. They may feel hungry at more frequent intervals and they will never really have that feeling of being full for very long. Meals become more frequent.
Leptin resistance can also lead to insulin resistance. Insulin is primarily released by the pancreas and its main function is to regulate cholesterol and blood sugar levels. (12) When a person’s diet includes more sugar-producing calories than the body needs (carbohydrates, sucrose, glucose) the liver ends up converting this first to triglycerides (blood sugar) and then body fat (sugar converted to store energy). If the liver is too busy regulating the sugar it cannot focus on the more important task of removing toxins from the body and regulating cholesterol. Likewise, because the insulin is too busy with the high blood sugar levels, it cannot focus on the cholesterol either. This is why cholesterol levels in the blood fluctuate in people who are obese and on their way to developing heart disease. The increased activity in the blood results in higher blood pressure and the development of atherosclerosis as well.
Finally, when the metabolism and endocrine system are thrown out of balance by the various hormones in excess in the body (leptin, insulin, triglycerides, cholesterol), the various glands in the brain and in the thyroid also go out of balance and especially in women, the ovaries begin to be affected as they are getting different levels of sex hormones than is normal.
This is the complicated process by which obesity can affect the reproductive system.
Obesity and estrogen; infertility and PCOS
In women at least, it is also known that adipose tissue can release excess amounts of estrogen, the hormone that is responsible for regulating the female sex drive. (13) In women, “one type of estrogen, known as estrogen receptor alpha or ER-alpha, plays a role in regulating food intake and energy expenditure.” (14) The studies conducted on animals showed that dwindling estrogen levels in the brain had the effect of making the subjects more tolerant to glucose and caused weight gain. Excess weight gain increased the amounts of leptin and estrogen in the body and negatively affected the function of insulin as well. (15) This vicious cycle of weight-gain and insulin resistance coupled with imbalances in estrogen levels and other sex hormones causes both abdominal obesity and the symptoms of PCOS - infertility due to abnormal ovulation in the ovaries. (16)
Infertility is the inability to conceive even after 1 year of unprotected intercourse, which is in a large number of cases (30-40%) mostly due to ovarian factors. (17) The complex web of hormones that are regulated by the endocrine system in which imbalances can lead to PCOS and infertility are “insulin, androgens, estrogen, progesterone, luteinizing hormone, follicle stimulating hormone, adrenal androgens, thyroid hormone, prolactin and many others.” (18)
How to reverse obesity and prevent the onset of PCOS
The key method to reverse this immediate and present danger for obese and overweight women is a lifestyle change that involves serious attempts at weight loss, an appropriate diet and the introduction of regular exercise in a sedentary lifestyle. (19) Even a small amount of weight-reduction can have almost immediate beneficial effects on health, as it is shown that there is a kind of “threshold” effect, observed in patients who lose weight to combat other illnesses related to the metabolic syndrome and obesity, such as sleep apnea. (20) It is only when a healthy lifestyle change fails to address the symptoms of PCOS that medication is usually recommended by doctors.
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(1) Polycystic ovary syndrome, Wikipedia. Retrieved July 26th, 2011, http://en.wikipedia.org/wiki/Polycystic_ovary_syndrome
(2) Anovulation, Wikipedia. Retrieved July 26th, 2011, http://en.wikipedia.org/wiki/Anovulation
(3) Amenorrhea, Wikipedia. Retrieved July 26th, 2011, http://en.wikipedia.org/wiki/Amenorrhea
(4) Hormonal acne, Acne, Wikipedia. Retrieved July 26th, 2011, http://en.wikipedia.org/wiki/Acne_vulgaris#Hormonal
(5) Polycystic ovary syndrome, Mayo Clinic, Dec. 8, 2009. Retrieved July 26th, 2011, http://www.mayoclinic.com/health/polycystic-ovary-syndrome/DS00423
(6) ibid.
(7) ibid.
(8) Obesity and the polycystic ovary syndrome, A Gambineri, C Pelusi, V Vicennati, U Pagotto and R Pasquali, International Journal of Obesity, July 2002, Volume 26, Number 7, Pages 883-896. Retrieved July 26th, 2011, http://www.nature.com/ijo/journal/v26/n7/abs/0801994a.html
(9) ibid.
(10) Leptin, Wikipedia. Retrieved July 26th, 2011, http://en.wikipedia.org/wiki/Leptin
(11) Diet-induced obesity leads to the development of leptin resistance in vagal afferent neurons, Guillaume de Lartigue, Claire Barbier de la Serre, Elvis Espero, Jennifer Lee, and Helen E. Raybould, AJP - Endo July 2011 vol. 301 no. 1 E187-E195. Retrieved July 26th, 2011, http://ajpendo.physiology.org/content/301/1/E187.short
(12) Liver, Wikipedia. Retrieved July 26th, 2011, http://en.wikipedia.org/wiki/Liver
(13) Estrogen, Wikipedia. Retrieved July 26th, 2011, http://en.wikipedia.org/wiki/Estrogen
(14) Revealing Estrogen's Secret Role In Obesity, Science Daily, Aug. 20, 2007. Retrieved July 26th, 2011, http://www.sciencedaily.com/releases/2007/08/070820145348.htm
(15) ibid.
(16) ibid.
(17) Insulin Sensitising Agents In PCOS Related Infertility, Aruna Nigam, Pooja Dwivedi, Pikee Saxena, Indian Journal of Medical Specialties. Retrieved July 26th, 2011, http://www.ijms.in/articles/1/2/insulini-sensitizing-agents-in-pcos-related-infertility.html
(18) ibid.
(19) ibid.
(20) APPENDIX IV. OBESITY AND SLEEP APNEA, The Clinical Guidelines on the Identification, Evaluation, and Treatment of Overweight and Obesity in Adults: The Evidence Report. Retrieved July 25th, 2011, http://www.nhlbi.nih.gov/guidelines/obesity/e_txtbk/appndx/apndx4.htm