Menstrual Symptoms And Keto: What Changes Can I Expect?

The ketogenic diet is a popular eating plan that has been linked to weight loss and other health benefits. However, it can also have an impact on a person's menstrual cycle. Some women who follow the keto diet report irregular periods or even a complete absence of their monthly cycle, a condition called amenorrhea. This side effect is believed to be caused by the rapid weight loss that can occur on a keto diet, which can alter hormone levels and affect ovulation. Additionally, the extreme carbohydrate restriction of the keto diet may also contribute to changes in hormones that regulate the menstrual cycle. While there is limited scientific research on the topic, there are many anecdotal reports of the keto diet affecting menstrual cycles. It is important to note that any dramatic change in diet or weight can impact the menstrual cycle, and individuals should consult a doctor before starting a new diet, especially if they are dealing with a medical issue.

Weight loss and its effect on estrogen levels

Estrogen is one of the primary female sex hormones, playing a role in puberty and the menstrual cycle. The ovaries are mainly responsible for its production, but the adrenal glands and fatty tissue also produce small amounts. Estrogen levels can affect weight, and weight loss can, in turn, affect estrogen levels.

Estrogen and Weight Loss

Estrogen levels naturally decrease during menopause, and this can lead to weight gain, particularly around the midsection. Estrogen helps regulate metabolism and control hunger signals, so lower levels can cause changes in a person's ability to recognize hunger, resulting in overeating.

Weight Loss and Estrogen

Weight loss can also affect estrogen levels. A study found that when participants lost an average of 17 pounds, their levels of estrone and estradiol dropped by 5.7% and nearly 10%, respectively.

Other Factors Affecting Estrogen Levels

In addition to menopause, other factors can cause low estrogen levels, including:

• Ovary removal
• Lactation
• Turner syndrome

Managing Weight Gain

To manage weight gain caused by low estrogen, the underlying cause should be treated. Doctors can advise on treatment plans and general weight maintenance tips, such as:

• Consuming fresh foods
• Staying hydrated
• Getting regular physical activity

Calorie restriction

When following a keto diet, it is important to ensure sufficient calorie intake. This is because keto diets can reduce hunger, making it easy to under-eat. To avoid this, track your food intake and supplement with keto-friendly snacks as needed. Be cautious with fasting, as this increases the risk of calorie restriction.

Additionally, a dramatic drop in carbohydrates can affect thyroid hormone production, which can impact the menstrual cycle. Therefore, it is recommended to gradually ease into carbohydrate restriction if cutting carbs quickly proves problematic.

Stress and cortisol levels

Stress is a well-documented disrupter of the menstrual cycle. The stress hormone cortisol can bind to most cells in the body, including cells that influence reproductive health. Dietary changes can be difficult, and going keto can be uniquely stressful. If you're dealing with keto flu symptoms from carb withdrawal, that's stressful too, even if you know the symptoms are temporary.

Following a keto diet will affect your cortisol levels. This is because limiting your carb intake to the degree that you do on keto causes a starvation response in the body. In an effort to increase energy levels in the face of having less sugar, the body triggers the release of stress hormones like cortisol. The cortisol and other stress hormones will then increase insulin resistance and stimulate gluconeogenesis to help increase blood sugar levels. In other words, the ketogenic diet is stressful for the body at first.

However, when you are finally in ketosis consistently, your cortisol levels will decrease because you will be using alternative fuel sources like ketones and fat and have a greater capacity to spare glycogen (your body's sugar stores). Thus, you will no longer need as much cortisol (and other stress hormones) to promote an increase in blood sugar levels.

Cortisol is one of your body's "fight-or-flight" hormones (adrenaline is the other). When you experience a stressful or frightening situation, your adrenal glands start pumping out cortisol, preparing your body to take immediate action. Cortisol pumps glucose into your bloodstream for fuel, increases heart rate and blood pressure, and shuts off digestive and reproductive function so you have more energy to dedicate to surviving whatever stressor is threatening you.

Cortisol also helps to control your sleep-wake cycle. It increases in the morning, waking your body up and making you alert enough to start your day. It also counteracts melatonin, a hormone that makes you sleepy, to help you wake up in the morning or stay awake during an emergency.

Chronic stress throws off your cortisol rhythm, resulting in either high or low cortisol levels. Both can wreak havoc on your blood sugar, cause high blood pressure, compromise immune function, disrupt sleep, and impact other vital aspects of your health — including mental health. High chronic stress levels have also been linked in studies to cortisol dysregulation.

If you're stressed out day-to-day and spend a lot of time in a fight-or-flight state, you probably have high cortisol levels. Your health habits, diet, environment, and even your thoughts influence your cortisol levels. Too much or too little cortisol can have a negative impact on your blood pressure, blood sugar levels, immune system, sleep, mood, memory, and more.

If you have high cortisol levels, starting a keto diet is a wise choice to lower your baseline cortisol.

Thyroid function

The thyroid gland is a small, butterfly-shaped gland located at the base of the neck. It plays an essential role in reproductive health by directly affecting the ovaries and interacting with sex hormone-binding globulin (SHBG), a protein that allows reproductive hormones to be carried throughout the body. Thyroid function can, therefore, have a significant impact on the menstrual cycle.

Thyroid problems can result in menstrual irregularities. Women with hypothyroidism (an underactive thyroid gland) may experience heavy menstrual bleeding, frequent menstrual periods, infrequent cycles, or absent menstrual cycles. They may also struggle to become or stay pregnant and have a higher risk of miscarriage. On the other hand, women with hyperthyroidism (an overactive thyroid gland) may experience absent or infrequent periods, light and short periods, and decreased fertility.

The keto diet may affect thyroid function. A drop in carbohydrate intake can potentially affect thyroid hormone production, which in turn can impact the menstrual cycle. However, the relationship between thyroid function and the menstrual cycle is complex, and more research is needed to fully understand the intricacies of this relationship.

It is important to note that not all women will experience menstrual cycle disruptions on the keto diet. Some women may even find that their reproductive health improves. Additionally, the keto diet can be beneficial for those with polycystic ovary syndrome (PCOS), a common cause of female infertility and menstrual irregularities.

If you are experiencing unusual menstrual symptoms, it is recommended to consult a healthcare professional to evaluate your thyroid function and overall health.

Insulin resistance

The keto diet is a high-fat, very low-carb approach that has been linked to weight loss and other health benefits. However, it can also affect the menstrual cycle, with some women reporting irregular periods or a complete halt in their cycle (amenorrhea). This is likely due to the rapid weight loss that can occur on the keto diet, which can alter hormone levels and affect ovulation.

The menstrual cycle is regulated by several hormones, including follicle-stimulating hormone (FSH), luteinizing hormone (LH), oestradiol (a form of estrogen), and progesterone. These hormones work together to release an egg from the ovaries (ovulation) and prepare the body for a possible pregnancy. When the body is in a state of insulin resistance, it can disrupt the delicate balance of these hormones, leading to menstrual irregularities.

During the first half of the menstrual cycle, or the follicular phase, FSH, LH, and estrogen levels are typically high. After ovulation, during the luteal phase, estrogen levels dip and progesterone levels rise. However, when the body is insulin resistant, it becomes less able to properly metabolize carbohydrates for energy during this second phase, leading to increased blood sugar, insulin levels, and fat storage.

The keto diet provides an alternative metabolic pathway to combat insulin resistance. By reducing carbohydrate intake, the body can bypass the impaired glucose uptake and help to balance blood sugar and hormones. This can be particularly beneficial during the luteal phase of the menstrual cycle when insulin resistance is typically higher.

While the keto diet can help to improve insulin resistance and regulate the menstrual cycle in some women, it is important to note that it may not work for everyone. Some women may experience continued menstrual irregularities or other side effects while on the keto diet. It is always recommended to consult with a doctor before starting any new diet, especially when dealing with a medical condition like PCOS.

Frequently asked questions