Keto And Periods: Weight Loss Impact Explained

The keto diet is a popular weight-loss strategy, but it can have some unexpected side effects, particularly for women. One of the less-discussed impacts of keto is its potential to disrupt the menstrual cycle, with some women reporting irregular periods or even a complete halt to their cycle. This phenomenon is known as amenorrhea and is often linked to rapid weight loss, which can alter hormone levels and affect ovulation. However, it's important to note that this isn't exclusive to keto, as very low-calorie diets or excessive exercise can also lead to amenorrhea. Additionally, the keto diet's restriction of carbohydrates may also play a role in menstrual irregularities by affecting the release of hormones like estrogen and luteinizing hormone. While keto can cause these changes, it's also worth noting that it may have benefits for women with polycystic ovarian syndrome (PCOS) by improving insulin function and reproductive health.

Keto can cause a rapid drop in estrogen levels, which can lead to irregular periods

The keto diet can cause a rapid drop in estrogen levels, which can lead to irregular periods. Estrogen is a hormone responsible for regulating the menstrual cycle. When the body enters a state of ketosis, it begins to burn fat instead of carbohydrates for energy. This can result in quick weight loss, which can then lead to a decrease in estrogen levels.

A study found that when participants lost an average of 17 pounds, their levels of the estrogen hormones estrone and estradiol decreased by 5.7% and nearly 10%, respectively. This drop in estrogen can disrupt ovulation and lead to amenorrhea, or the absence of a menstrual period.

Additionally, the keto diet's restriction of carbohydrates may also contribute to irregular periods. Carbohydrate restriction can lead to changes in the luteinizing hormone, which is released by the brain and contributes to regular ovulation. When carb intake is limited, luteinizing hormone levels may be compromised, leading to amenorrhea or hypomenorrhea (short, light periods).

While the keto diet can cause disruptions to the menstrual cycle, it is important to note that any dramatic weight loss or dietary change can have similar effects. Additionally, the impact of the keto diet on the menstrual cycle may vary from person to person. Some women may experience irregular periods or amenorrhea, while others may find that their periods become more regular, especially if they are overweight.

If you are experiencing menstrual irregularities while on the keto diet, it is recommended to consult a doctor, as missed or abnormal periods can be due to various health conditions. Additionally, it is important to ensure you are getting enough calories and nutrients while on the keto diet, as calorie restriction and nutritional deficiencies can also impact the menstrual cycle.

Calorie restriction on keto can interfere with the female reproductive cycle

The keto diet is a high-fat, low-carbohydrate diet that has been linked to weight loss and other health benefits. However, it can also have a strange effect on the menstrual cycle. Some women on the keto diet report irregular periods or even the disappearance of their monthly cycle altogether – a phenomenon called amenorrhea. In fact, amenorrhea seems to be one of the main side effects of the diet, with 45% of female participants in one study reporting menstrual dysfunction.

One reason for this may be rapid weight loss. If someone is cutting too many calories, cycle irregularities can develop. This can happen with any diet, but keto has been shown to lead to drastic weight loss. A previous study found that one year into a low-calorie version of keto, most participants lost at least 10% of their initial body weight. The keto diet can result in quick weight loss because it causes the body to burn fat instead of carbohydrates through a process called ketosis.

Another factor could be the stress associated with dietary change. The stress hormone cortisol can bind to most cells in the body, including cells that influence reproductive health. Dietary change can be difficult, and giving up carbohydrates can be particularly challenging. Additionally, dealing with keto flu symptoms from carb withdrawal can be stressful, even if temporary.

Calorie restriction on keto can also interfere with thyroid function. Disruptions in thyroid hormones are linked to disruptions in menstruation. Thyroid hormones are sensitive not only to calorie restriction but also to carb restriction. That's why both T3 and T4 often decline on low-carb diets. However, it's unclear whether this decline is a cause for concern, as low-carb diets may be therapeutic for certain thyroid disorders.

To maintain a healthy menstrual cycle while on keto, it's important to ensure adequate calorie intake, be cautious with fasting, and prioritise nutritious, whole foods. It's also worth noting that it may take a couple of months for things to stabilise after a dietary change, as hormones adjust. If issues persist, it may be worth trying another menstruation diet plan, such as Paleo or Mediterranean, as keto doesn't work for everyone.

Keto can be stressful, triggering a stress response in the body and affecting hormones

The keto diet can be stressful for the body, triggering a stress response that affects hormones. This is because limiting carbohydrates to a significant degree causes a starvation response. In an effort to increase energy levels, the body triggers the release of stress hormones like cortisol.

Cortisol and other stress hormones will then increase insulin resistance and stimulate gluconeogenesis to help increase blood sugar levels. This can lead to an increase in cortisol, the "stress" hormone, as confirmed by hormonal naturopathic doctor Natasha Turner, ND. Turner states that:

> "According to the keto rules, followers are [usually] only allowed 30 grams of carbs a day from green vegetables. No starchy carbs. No fruit... This puts stress on the body, which raises cortisol levels."

This increase in cortisol can lead to weight gain, as stressed bodies can burn protein for energy instead of fat or carbs, spiking cortisol levels. This can also cause problems like acne and worsen conditions like endometriosis or PCOS.

Furthermore, a high-fat diet can lead to increased estrogen production, which is also linked to weight gain. Higher estrogen levels suppress the thyroid, which controls the metabolic process, including weight management. Thus, keto can be a "triple whammy", as Turner describes it:

> "One [effect] is that it increases your risk of having high cortisol because of the carbohydrate restriction. Two, it’s going to increase the production of estrogen because of the high-fat diet. And three, these two changes—the high cortisol and high estrogen—suppress your thyroid and make you more prone to weight gain."

Therefore, while keto may lead to weight loss, it can also be stressful for the body, triggering a stress response and affecting hormones, which can, in turn, lead to weight gain and other health issues.

A drop in carbohydrates can affect thyroid hormone production, which is linked to disruptions in menstruation

The keto diet is a low-carb, high-fat, and moderate-protein diet that aims to put your body in a metabolic state called ketosis, where it burns fat instead of carbohydrates for energy. While the keto diet is often associated with weight loss, it can also affect thyroid function and menstrual cycles.

Thyroid hormones play a crucial role in maintaining and regulating energy metabolism. The thyroid gland produces thyroid-stimulating hormones (TSH) that are partly made up of glucose molecules. When carb intake is drastically reduced, as in the keto diet, the conversion of the inactive thyroid hormone thyroxine (T4) to the active form triiodothyronine (T3) declines. This decrease in T3 can impact thyroid function, as T3 is the active thyroid hormone necessary for metabolism.

Additionally, the keto diet's restriction of carbohydrates can lead to changes in the luteinizing hormone (LH), which contributes to regular ovulation. When carb intake is limited, LH may be compromised, leading to amenorrhea (absence of periods) or hypomenorrhea (short and light periods).

The disruption in thyroid function caused by a drop in carbohydrate intake can have a ripple effect on menstrual cycles. Studies have shown that both hypothyroid and hyperthyroid women experience a greater prevalence of menstrual disturbances compared to euthyroid women. Specifically, hypothyroid women may suffer from oligomenorrhea (infrequent cycles) and menorrhagia (heavy menstrual bleeding), while hyperthyroid women are more likely to experience hypomenorrhea.

In summary, a decrease in carbohydrate intake, as seen in the keto diet, can affect thyroid hormone production by reducing the conversion of T4 to T3. This, in turn, can lead to disruptions in menstruation, such as amenorrhea or changes in the luteinizing hormone, ultimately affecting ovulation and menstrual regularity.

Keto can be beneficial for women with polycystic ovarian syndrome (PCOS) by improving insulin function and reducing insulin resistance

The keto diet can be beneficial for women with polycystic ovarian syndrome (PCOS) by improving insulin function and reducing insulin resistance. PCOS is a common hormonal condition that affects around one in ten women during their childbearing years. It is caused by insulin resistance, which means the body does not respond appropriately to the hormone insulin, leading to elevated blood sugar and insulin levels. This can result in excess weight and body fat, particularly dangerous visceral fat in the lower abdomen.

The keto diet is a low-carb, high-fat diet that significantly reduces carbohydrate intake, forcing the body to burn fat for energy instead of carbohydrates. This reduction in carbohydrates can help improve insulin sensitivity and decrease insulin resistance, which is beneficial for managing PCOS. Several studies have found that the keto diet improves insulin sensitivity and reduces insulin levels in women with PCOS.

In addition to improving insulin function, the keto diet can also help with weight loss in people with obesity and PCOS. Weight loss is recommended for women with PCOS as it can help improve insulin resistance and promote hormonal balance. The keto diet's dual effect on insulin and weight loss makes it a promising approach for managing PCOS.

Furthermore, the keto diet has been found to reduce excess androgens, which are male sex hormones that can be elevated in women with PCOS due to insulin resistance. By reducing insulin resistance, the keto diet can help lower androgen levels and restore normal ovarian function, which can improve fertility.

While the keto diet shows potential for managing PCOS, it is essential to consult with a healthcare professional before starting this or any other dietary intervention. Additionally, larger and longer-term studies are needed to fully understand the long-term effects of the keto diet on PCOS.

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