Polycystic ovary syndrome, or PCOS, affects as many as 18% of all women of childbearing age. The condition occurs when a woman’s body produces too much of a group of hormones called androgens, mainly testosterone. Menstrual irregularity, obesity and even infertility can result.
The first line of treatment is usually hormonal birth control, said UIC nutrition professor Krista Varady. But there can be negative side effects on mood, libido and metabolism, plus an increased risk of stroke in some people, Varady said.
“We’re looking for other ways to lower testosterone levels in these women,” he said. “One of the ways is through weight loss. If someone loses around 5% of their body weight, they can actually help lower testosterone levels and sidestep any kind of medication.”
A new study led by Varady examined how one method of weight loss – intermittent fasting – affects hormones and symptoms in PCOS patients. Published in Natural Medicineresearch shows that restricting eating to a window of six hours a day decreases testosterone without negatively affecting female hormones. Studies have also shown that losing weight by counting calories reduces testosterone.
However, some critics of intermittent fasting have posited that the diet disrupts female hormones, said Varady.
“There is a particular sentiment that intermittent fasting is really bad for women.” This is not true, he said. “This study and several studies published by our lab and others show that intermittent fasting can improve women’s hormone levels, especially in women with PCOS.”
Varady and his colleagues studied a type of intermittent fasting called time-restricted eating. In this method, you only eat for six or eight hours a day. During the remaining 18 or 16 hours, you fast with calorie-free drinks and water until the next day.
Simply put, the strategy helps people eat less, Varady said. As well as counting calories, the method Varady and his colleagues tested with intermittent fasting in the study. But intermittent fasting has some additional benefits.
“It’s a way to reduce energy intake without having to count complicated calories,” he says of intermittent fasting. Varady and others have shown in previous work that eating only during an eight-hour window can cut about 300 to 500 calories a day.
In addition to obesity and insulin resistance, which increase the risk of diabetes and heart disease, PCOS can cause ovarian cysts, acne and facial hair growth.
In a group of 76 pre-menopausal women with PCOS, researchers tested how the results differed after six months between time-limited eating between 1 and 7 pm daily and counting calories. Both diet schemes ended up cutting participants’ intake by about 200 calories per day, the team found, leading to an average weight loss of about 10 pounds for six months.
Both groups also experienced a decrease in testosterone concentration. But only time-restricted eating reduces the free androgen index, the ratio between testosterone and the protein that transports it into the blood, which is a sign of how much active testosterone reaches the body’s tissues. It also raises A1C levels, a risk marker for diabetes, Varady said.
Although intermittent fasting does not reduce other symptoms of PCOS, such as menstrual irregularity, Varady suggests that those symptoms may improve with longer time on the diet and greater weight loss.
About 80% of participants in the occasional diet group said they intended to continue the diet, Varady said.
The study was a team effort among professors of nutrition in the department of kinesiology and nutrition in the College of Applied Health Sciences. Sofia Cienfuegos designed and ran the study with Varady, while Kelsey Gabel, Lisa Tussing-Humphreys and Vanessa Oddo worked as well.
“We all have a strong interest in women’s health, and we designed this together and ran it together,” Varady said. “It’s one of the biggest nutrition department collaborations we’ve ever done.”
Other UIC authors on the study include Sarah Corapi, Mary-Claire Runchey, Jodie Lyons, Maria Alonso de Leon, Vasiliki Pavlou and Mark Ezpeleta from the College of Applied Health Sciences; Julienne Sanchez from the College of Medicine; and Shuhao Lin, formerly of UIC and now with the Mayo Clinic.
Story by Tess Joosse
Disclaimer: AAAS and EurekAlert! is not responsible for the accuracy of news broadcasts posted to EurekAlert! by the contributing agency or to use any information through the EurekAlert system.
Polycystic ovary syndrome, or PCOS, affects as many as 18% of all women of childbearing age. The condition occurs when a woman’s body produces too much of a group of hormones called androgens, mainly testosterone. Menstrual irregularity, obesity and even infertility can result.
The first line of treatment is usually hormonal birth control, said UIC nutrition professor Krista Varady. But there can be negative side effects on mood, libido and metabolism, plus an increased risk of stroke in some people, Varady said.
“We’re looking for other ways to lower testosterone levels in these women,” he said. “One of the ways is through weight loss. If someone loses around 5% of their body weight, they can actually help lower testosterone levels and sidestep any kind of medication.”
A new study led by Varady examined how one method of weight loss – intermittent fasting – affects hormones and symptoms in PCOS patients. Published in Natural Medicineresearch shows that restricting eating to a window of six hours a day decreases testosterone without negatively affecting female hormones. Studies have also shown that losing weight by counting calories reduces testosterone.
However, some critics of intermittent fasting have posited that the diet disrupts female hormones, said Varady.
“There is a particular sentiment that intermittent fasting is really bad for women.” This is not true, he said. “This study and several studies published by our lab and others show that intermittent fasting can improve women’s hormone levels, especially in women with PCOS.”
Varady and his colleagues studied a type of intermittent fasting called time-restricted eating. In this method, you only eat for six or eight hours a day. During the remaining 18 or 16 hours, you fast with calorie-free drinks and water until the next day.
Simply put, the strategy helps people eat less, Varady said. As well as counting calories, the method Varady and his colleagues tested with intermittent fasting in the study. But intermittent fasting has some additional benefits.
“It’s a way to reduce energy intake without having to count complicated calories,” he says of intermittent fasting. Varady and others have shown in previous work that eating only during an eight-hour window can cut about 300 to 500 calories a day.
In addition to obesity and insulin resistance, which increase the risk of diabetes and heart disease, PCOS can cause ovarian cysts, acne and facial hair growth.
In a group of 76 pre-menopausal women with PCOS, researchers tested how the results differed after six months between time-limited eating between 1 and 7 pm daily and counting calories. Both diet schemes ended up cutting participants’ intake by about 200 calories per day, the team found, leading to an average weight loss of about 10 pounds for six months.
Both groups also experienced a decrease in testosterone concentration. But only time-restricted eating reduces the free androgen index, the ratio between testosterone and the protein that transports it into the blood, which is a sign of how much active testosterone reaches the body’s tissues. It also raises A1C levels, a risk marker for diabetes, Varady said.
Although intermittent fasting does not reduce other symptoms of PCOS, such as menstrual irregularity, Varady suggests that those symptoms may improve with longer time on the diet and greater weight loss.
About 80% of participants in the occasional diet group said they intended to continue the diet, Varady said.
The study was a team effort among professors of nutrition in the department of kinesiology and nutrition in the College of Applied Health Sciences. Sofia Cienfuegos designed and ran the study with Varady, while Kelsey Gabel, Lisa Tussing-Humphreys and Vanessa Oddo worked as well.
“We all have a strong interest in women’s health, and we designed this together and ran it together,” Varady said. “It’s one of the biggest nutrition department collaborations we’ve ever done.”
Other UIC authors on the study include Sarah Corapi, Mary-Claire Runchey, Jodie Lyons, Maria Alonso de Leon, Vasiliki Pavlou and Mark Ezpeleta from the College of Applied Health Sciences; Julienne Sanchez from the College of Medicine; and Shuhao Lin, formerly of UIC and now with the Mayo Clinic.
Story by Tess Joosse
Disclaimer: AAAS and EurekAlert! is not responsible for the accuracy of news broadcasts posted to EurekAlert! by the contributing agency or to use any information through the EurekAlert system.
