Clinical symptoms of RED-S may include disordered eating, fatigue, hair loss, cold hands and feet, dry skin, noticeable weight loss, increased healing time from injuries (e.g., lingering bruises), increased incidence of bone fracture and cessation of menses. Affected athletes may also struggle with low self-esteem and depression. Upon physical examination, a physician may also note the following symptoms: elevated carotene in the blood, anemia, orthostatic hypotension, electrolyte irregularities, hypoestrogenism, vaginal atrophy, and bradycardia. An athlete may show signs of restrictive eating, but not meet the clinical criteria for an eating disorder. They may also display subtle menstrual disturbances, such as a change in menstrual cycle length, anovulation, or luteal phase defects, but not yet have developed complete amenorrhea. Likewise, an athlete's bone density may decrease, but may not yet have dropped below her age-matched normal range. These signs can be considered "occult," as no one symptom may be severe enough to seek medical attention, leaving the triad to go unnoticed or untreated. Disordered eating<unk>  availability is defined as<unk>  intake minus<unk>  expended.<unk>  is taken in through food consumption. Our bodies expend<unk>  through normal functioning as well as through exercise. In the case of female athlete triad, low<unk>  availability may be due to eating disorders, but not necessarily so. Athletes may experience low<unk>  availability by exercising more without a concomitant change in eating habits, or they may increase their<unk>  expenditure while also eating less. Disordered eating is defined among this situation due to the low caloric intake or low<unk>  availability. While most athletes do not meet the clinical criteria to be diagnosed with an eating disorder such as anorexia nervosa or bulimia nervosa, many will exhibit disordered eating habits such as fasting, as well as avoiding certain types of food the athlete thinks are "bad" (such as foods containing fat). There are multiple factors that play in encouraging athletes to aim for a more lean body type, such as the culture and the individual. More severe examples of disordered eating habits may include binge-eating; purging; and the use of diet-pills, laxatives, diuretics, and enemas. By restricting their diet, the athlete may worsen their problem of low<unk>  availability. Having low dietary<unk>  from excessive exercise and/or dietary restrictions leaves too little<unk>  for the body to carry out normal functions such as maintaining a regular menstrual cycle or healthy bone density. Amenorrhea Amenorrhea, defined as the cessation of a woman’s menstrual cycle for more than three months, is the second disorder in the triad. Weight fluctuations from dietary restrictions and/or excessive exercise affect the hypothalamus’s output of gonadotropic hormones. Gonadotropic hormones “stimulate growth of the gonads and the secretion of sex hormones.” (e.g. gonadotropin-releasing hormone, lutenizing hormone and follicle stimulating hormone.) These gonadotropic hormones play a role in stimulating estrogen release from the ovaries. Without estrogen release, the menstrual cycle is disrupted. Exercising intensely and not eating enough calories can lead to decreases in estrogen, the hormone that helps to regulate the menstrual cycle. As a result, periods may become irregular or stop altogether. There are two types of amenorrhea. A woman who has been having her period and then stops menstruating for ninety days or more is said to have secondary amenorrhea. In the case of RED-S, the majority of secondary amenorrhea cases are attributed to functional hypothalamic amenorrhea (FHA), an adaptive mechanism to preserve<unk>  for survival and vital processes rather than reproduction when<unk>  balance is low. Primary amenorrhea is characterized by delayed menarche (the onset of menses during puberty). Delayed menarche may be associated with delay of the development of secondary sexual characteristics. Osteoporosis Osteoporosis is defined by the National Institutes of Health as ‘‘a skeletal disorder characterized by compromised bone strength predisposing a person to an increased risk of fracture.’’ Low estrogen levels and poor nutrition, especially low calcium intake, can lead to osteoporosis, the third aspect of the triad. This condition can ruin a female athlete's career because it may lead to stress fractures and other injuries. Patients with female athlete triad get osteoporosis due to hypoestrogenemia, or low estrogen levels. With estrogen<unk> , the osteoclasts live longer and are therefore able to resorb more bone. In response to the increased bone resorption, there is increased bone formation and a high-turnover state develops which leads to bone loss and perforation of the trabecular plates. As osteoclasts break down bone, patients see a loss of bone mineral density. Low bone mineral density renders bones more brittle and hence susceptible to fracture. Because athletes are active and their bones must endure mechanical stress, the likelihood of experiencing bone fracture is particularly high. Additionally, because those suffering with female athlete triad are also restricting their diet, they may also not be consuming sufficient amounts vitamins and minerals which contribute to bone density; not getting enough calcium or vitamin D further exacerbates the problem of weak bones. Bone mass is now thought to peak between the ages of 18-25. Thus, behaviors which result in low bone density in youth could be detrimental to an athlete’s bone health throughout her lifetime. In addition, ovulation is the primary way that females create the hormone progesterone. When an ovum is released from the ovary, the structure that remains develops into the corpus luteum. The corpus luteum emits the hormone progesterone during the 10–16 days of the luteal phase. Without experiencing regular, ovulatory menstrual cycles, the female is not secreting the hormone progesterone during the luteal phase of her cycle. Progesterone directly stimulates osteoblasts to make new bone. Therefore if the woman is not ovulating, she is not creating progesterone, and misses out on this opportunity to stimulate new bone growth.
Relative energy deficiency in sport
Ergogenic use of anabolic steroids
Obesity-associated morbidity
Chronic stress
Benefits of physical activity
Metabolically healthy obesity
Lifestyle causes of type 2 diabetes
Stress hyperglycemia