Keto Diet: Stopping Periods Sooner Than You Think

The ketogenic diet has become popular for its weight loss effects and other health benefits. However, it can also affect the regularity of the menstrual cycle. A rapid shift in dietary patterns, such as the low-carb keto diet, can cause period problems. A study published in 2003 reported that 45% of female participants experienced menstrual irregularities or amenorrhea. This is because the female menstrual cycle is very sensitive to extreme dietary changes and weight reduction. A low-calorie keto diet can also lead to stress and affect the secretion of female sex hormones, resulting in irregular or absent periods. However, for women with polycystic ovarian syndrome (PCOS), the ketogenic diet can help restore hormonal balance and induce periods. The relationship between keto and periods is complex and varies for each individual.

Keto can cause amenorrhea

The keto diet can cause amenorrhea, or the absence of a menstrual cycle, in some women. Amenorrhea seems to be one of the main side effects of the keto diet, with 45% of female participants in one study reporting menstrual dysfunction. This is likely due to the rapid weight loss that can occur on the keto diet, as well as the extreme restriction of carbohydrates.

Weight Loss

When someone loses weight rapidly, their estrogen levels can drop, which can impact ovulation and cause irregular or missed periods. This can happen with any diet that involves drastic weight loss, but keto has been shown to lead to quick weight loss. A study published in the Journal of Obesity and Weight Loss Therapy in 2018 noted that keto caused disruption to women's hormonal systems.

Carbohydrate Restriction

Extreme carbohydrate restriction may also lead to changes in the luteinizing hormone, which contributes to regular ovulation. When carbs are restricted, the luteinizing hormone may be compromised, leading to amenorrhea or hypomenorrhea (short, light periods). A drop in carbohydrates can also affect thyroid hormone production, which may impact the menstrual cycle, especially for those with thyroid-related diseases.

Hormonal Changes

The keto diet can lead to hormonal changes that influence the menstrual cycle. The rapid weight loss and extreme carbohydrate restriction associated with keto can affect the release of hormones from the brain, disrupting ovulation and leading to amenorrhea. One of the main hormones involved is gonadotropin-releasing hormone (GnRH), which stimulates the production of other hormones such as estrogen and progesterone. A decrease in GnRH can cause a domino effect, leading to reduced levels of other hormones and disrupting ovulation.

Individual Factors

The impact of the keto diet on the menstrual cycle may also depend on individual factors such as age, ancestry, and insulin resistance. Women over 35 may be less likely to experience amenorrhea on keto, as their ovulatory cycles are more robust. Women with insulin resistance may benefit from a low-carb or keto diet, as it can promote regular ovulation and periods. Additionally, women descended from agrarian ancestors may be more sensitive to carbohydrates as a dietary signal.

Weight loss affects estrogen levels

Weight loss can affect estrogen levels, and estrogen levels can affect weight loss. Estrogen is one of the two primary female sex hormones, and it plays a role in the onset of puberty and the menstrual cycle. Estrogen is responsible for regulating the menstrual cycle, and as weight drops, so do estrogen levels.

The keto diet can lead to rapid weight loss, which can, in turn, alter estrogen levels and cause irregular or absent periods. This can happen with any diet, not just keto, though keto has been shown to lead to drastic weight loss.

Estrogen levels can also be affected by other factors, such as ovary removal, lactation, and Turner syndrome. Estrogen levels remain low after a person has given birth and while breastfeeding or nursing. This hormonal change helps encourage milk production and prevent ovulation and any further conception right away.

A person who has had both of their ovaries surgically removed will go through sudden menopause, and they will no longer produce the same amount of estrogen. Turner syndrome is a genetic condition that affects females, and a person with the condition will usually begin estrogen replacement therapy around the time of puberty, which can help reduce weight gain.

Estrogen has links with how the body controls weight gain, and changes in estrogen levels could then lead to changes in body weight. Estrogen helps regulate metabolism and body weight, so lower levels may lead to weight gain. Estrogen also helps control hunger signals, which may help prevent excess calorie consumption. When estrogen levels reduce, this can cause changes in a person’s ability to recognize hunger, which may result in overeating.

Calorie restriction impacts the menstrual cycle

Calorie restriction can have a significant impact on the menstrual cycle, with excessive or rapid weight loss often leading to hormonal imbalances that disrupt the normal menstrual cycle. This is true for diets like keto, which can lead to rapid weight loss and, in turn, affect estrogen and progesterone levels, causing irregular periods or amenorrhea (absence of periods).

The link between calorie restriction and menstrual irregularities has been observed in several studies. One study found that a calorie deficit of 22-42% resulted in menstrual disturbances in young, previously sedentary women. The disturbances included luteal phase defects, oligomenorrhea (irregular cycles), and anovulatory cycles. Another study showed that a very low-calorie diet could lead to amenorrhea due to anovulation, or lack of ovulation. This occurs when certain hormones in the brain that regulate ovulation drop, preventing or delaying ovulation and leading to menstrual irregularities.

The impact of calorie restriction on the menstrual cycle is not limited to extreme diets like keto. Any diet that involves excessive calorie restriction can potentially affect reproductive health. This includes restrictive eating disorders like anorexia nervosa, rapid weight loss, or famine. In these cases, the body may not be getting enough calories to meet energy demands, leading to a disruption in the hormones that regulate the menstrual cycle.

It is important to note that being overweight can also lead to menstrual disruptions or amenorrhea. When the body has too many fat cells, it can produce an excessive amount of estrogen. While there is no ovulation, the uterine wall continues to build up the lining, leading to heavier and longer periods when menstruation does occur.

Overall, the relationship between calorie restriction and the menstrual cycle is complex and influenced by various factors such as weight, diet composition, and individual differences. However, it is clear that excessive calorie restriction can disrupt the normal hormonal balance and lead to menstrual irregularities, including amenorrhea.

Low-carb diets may improve fertility

Low-carb diets have been linked to weight loss, but they can also have an impact on fertility. For women with polycystic ovarian syndrome (PCOS), a hormonal disorder that affects fertility, a low-carb diet may help to restore regular periods and improve fertility.

PCOS is a hormonal disorder that affects around 1 in 10 women. It is characterised by high levels of male hormones (hyperandrogenism) and infrequent ovulation, and it is a leading cause of infertility. While it is possible to get pregnant with PCOS, it can be challenging.

A low-carb diet can help to reduce insulin levels and improve insulin sensitivity, which can lead to a more favourable hormonal balance and improved menstrual function. Additionally, weight loss of as little as 5-10% can improve hormonal imbalances and reduce the risk of miscarriages, further supporting fertility.

For women without PCOS, a low-carb diet may still have benefits for fertility. A review of 14 randomised controlled trials found that women who consumed fewer calories and refined carbs were more likely to become pregnant and also experienced weight loss and improved ovulation.

While a low-carb diet may improve fertility, it is important to note that rapid weight loss can also disrupt the menstrual cycle and lead to irregular periods or amenorrhea (absence of periods). Therefore, it is crucial to ensure that any weight loss is gradual and that calorie intake remains adequate.

Additionally, a low-carb diet may not be suitable for everyone, and it is always advisable to consult a healthcare professional before making significant dietary changes, especially when dealing with a medical issue like infertility.

Keto can help women with PCOS

The keto diet is a high-fat, low-carb approach that has been linked to weight loss and other health benefits. However, it can also affect your period, with some women reporting irregular periods or a complete stop in their cycle. This phenomenon is called amenorrhea and is likely due to rapid weight loss and the subsequent hormonal changes that come with it.

Now, here's how keto can help women with PCOS:

Weight Loss

PCOS is often associated with obesity and weight gain or difficulty losing weight. The keto diet can help women with PCOS lose weight. In one study, participants lost an average of 21 pounds (9 kg) in 45 days. Another study found that participants lost an average of nearly 21 pounds (9 kg) in 12 weeks. Losing weight is recommended for women with PCOS, as it can help improve insulin resistance and promote hormonal balance.

Improved Insulin Sensitivity

PCOS is characterized by insulin resistance, where the body doesn't respond appropriately to the hormone insulin, which helps regulate blood sugar levels and fat storage. The keto diet has been shown to improve insulin sensitivity, which can be beneficial for PCOS management. In several studies, a keto diet resulted in significant improvements in blood sugar and insulin levels, indicating higher insulin sensitivity.

Hormone Balance

PCOS is caused by a hormonal imbalance in women, with elevated levels of testosterone and other androgen hormones. The keto diet can help balance hormones by reducing testosterone levels and improving the balance of sex hormones. In one study, a keto diet led to a significant reduction in the LH/FSH ratio, which is often elevated in women with PCOS. Additionally, the keto diet can help decrease inflammation, which is one of the factors contributing to PCOS.

Normalized Menstrual Cycles

Women with PCOS often experience irregular periods or amenorrhea (absence of periods). The keto diet has been shown to normalize menstrual cycles in women with PCOS. In one study, 12 out of 17 women reported improved regularity in their periods, and 5 women had their periods return after not having one for several years.

Improved Fertility

PCOS is a major cause of infertility in women. However, the keto diet may improve fertility in women with PCOS. In one study, 5 out of 17 women became pregnant after many unsuccessful prior attempts. The keto diet may help restore regular periods and make women more responsive to fertility treatments.

While keto can be beneficial for women with PCOS, it is important to note that it is a very restrictive diet and may be difficult to follow long-term. Larger and longer-term studies are needed to fully understand the effects of keto on PCOS. If you are considering the keto diet to manage your PCOS, be sure to work closely with a healthcare professional.

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