The ketogenic diet has become popular because of its numerous health benefits. However, the most notable effect of the ketogenic diet which has led to its massive popularity amongst bloggers and celebrities is its weight loss effect.
If you're a woman and are thinking about starting this popular low-carb diet, you might be wondering about the effect of keto on the menstrual cycle.
So, is there any relationship between keto and periods? This article explores the impact of keto on your period in detail.
Unfortunately, yes. There is some evidence to suggest a negative impact of keto on periods. Ketogenic diets can influence the regularity of your menstrual cycle. A study published in 2003 reported menstrual irregularity as one of the most common side effects of the ketogenic diet in adolescent females.1
When on keto, period problems were reported in 45% of the female participants. This is because the female menstrual cycle is very sensitive to extreme dietary changes and weight reduction.2
A rapid and sudden shift in dietary patterns can affect the regularity of your periods. So when on keto, period problems might be a common occurrence.
However, one thing to be kept in mind is that the effect of keto on the menstrual cycle varies for each individual woman.
Women with polycystic ovarian syndrome (PCOS) have irregular periods, impaired fertility, and frequently suffer from obesity. Research indicates a positive impact of keto on the period in women with PCOS. Women who were initiated on a ketogenic diet reported regular periods shortly after initiating the diet, and two women were able to conceive naturally. Therefore, by inducing weight loss, the ketogenic diet was able to restore menstruation and fertility in women with PCOS.3
A healthy body weight is necessary for normal periods. Excessive weight reduction and low body mass index can impair the regularity of your period.4 Therefore, it is necessary to avoid dramatic and excessive weight loss. So when on keto, period problems can be avoided by being on the lookout for drastic weight changes.
So what's the link between keto, periods and ketosis? Ketosis occurs when there are low carbohydrates for metabolism and the body breaks down fats for metabolism.
During the later phase of the menstrual cycle, progesterone dominates. As progesterone prepares the body for pregnancy, it stimulates fat deposition as more energy reserves are required for the maintenance of pregnancy.
As a result, achieving ketosis might hypothetically become difficult during the period because of high progesterone levels. There is no available research that has documented the effect of menstruation on ketosis.
During the premenstrual phase, some females might experience carbohydrate cravings. During the luteal phase of the menstrual cycle, women experience these cravings because the uterus is preparing for a potential pregnancy that requires the body to store energy. The changes in the hormonal balance of estrogen and progesterone could be the possible culprit behind high-carb food cravings.5-6
Ketogenic diets are low in carbs, which can make them unsustainable or difficult to follow when you're on your period. Caving into carbohydrate cravings immediately following or during your period can potentially kick you out of ketosis.
In addition, the hormone progesterone, which dominates the premenstrual phase, favors fat deposition and can potentially affect lipid metabolism.7 This can make achieving ketosis very difficult when you're on your period.
Some women report experiencing keto period weight gain. However, the majority of females already experience some form of weight gain during their period. This weight gain is normal and is caused due to hormonal fluctuations during your period.
It is important to avoid weighing yourself just before or during your period because this weight is “water weight.” Water retention is a common symptom of premenstrual syndrome and can affect up to 92% of women.8
Therefore, instead of obsessing about the possible effect of keto on period weight gain, you should notice the overall pattern of weight reduction over a month. That might be a more accurate indicator of weight loss associated with the ketogenic diet.
On keto, period problems are a common issue because of its potential effect on the secretion of female sex hormones.
The female reproductive cycle is very sensitive to the availability of energy. The menstrual cycle is controlled by the hormones released by the hypothalamic-pituitary-ovarian (HPO) axis. The secretion of reproductive hormones is affected by stress, exercise, low caloric intake, and weight loss.9
As a result, weight reduction or caloric restriction induced by low-carb diets can reduce the secretion of female sex hormones. So on keto, menstrual cycle abnormalities such as irregular or absent periods can occur. It is medically described as “functional hypothalamic amenorrhea.”
Another way through which keto can affect periods is by inducing a state of stress. A low-calorie diet increases the secretion of the stress hormone “cortisol,” which can interfere with the hypothalamic-pituitary-ovarian axis.
A study published in 2018 demonstrated that women with functional hypothalamic amenorrhea or absent periods had higher levels of the stress hormone. Stress is a very common cause of infertility in women. Therefore, prolonged periods of chronic stress and caloric restriction induced by keto might potentially affect the normal functioning of female reproductive hormones.10-11
However, in women with polycystic ovarian syndrome, the ketogenic diet can help restore the hormonal imbalance. Women with PCOS have higher levels of circulating insulin and androgens with associated lower levels of estrogen. Research has demonstrated that a low-carb diet can help lower the levels of androgens and help reverse the symptoms in women with PCOS.12
For certain individuals, the ketogenic diet for women can be an effective way to lose weight and regulate their periods. Women with PCOS may experience a positive effect of keto on their period.
However, for pregnant or lactating women, it might pose certain health risks which women should be aware of. Pregnant women who are taking low carbohydrate diets might have a higher risk of having infants with spinal cord defects. There is also evidence of lactating women developing severe life-threatening ketosis when on a keto diet.13-14
For non-pregnant women, the low-carb diet can be an effective way to lose weight.
In addition, it might also be used as an adjunct treatment for certain types of cancers in women. In one study, women who had been diagnosed with ovarian or endometrial cancer were given the ketogenic diet. After 12 weeks of following the diet, the women had lower levels of insulin-like growth factor. There were elevated levels of ketone bodies which are considered detrimental to the growth of cancer cells. In another study, low-carb diets improve the quality of life and physical performance in women with breast cancer.15-16
However, there is evidence to suggest that low-carb diets are more effective for men compared to women. A study published in 2020 reported the sex differences in response to treatment of obesity using low-carb diets. The male participants in the study experienced a significantly greater weight loss compared to women.17 Despite the gender differences in response to keto, women can still use this diet as an effective weight-loss method.
Menstrual irregularities and dysfunction are commonly reported problems with ketogenic diets. So how are keto and period irregularities possibly related?
Women following low-carb diets might encounter endocrine abnormalities which can mess with their period.1 Many women experience either complete disappearance of their periods or irregular, abnormal periods.
If you’re experiencing heavy and prolonged menstruation, you should consult your gynecologist and healthcare physician. They will be able to properly assess your situation and see if there’s something other than keto that could be causing your symptoms. They might also advise discontinuing the ketogenic diet for some time to see if it helps with the problem.
The relationship between keto and periods is complicated because each person is so different. For women with PCOS doing keto, it can help establish the regularity of their cycle. For others, a low-carb diet can disturb the regularity of the menstrual cycle through its effect on the female reproductive hormones.
There is not enough research that reports the association between heavy bleeding, periods, and keto. However, it is often a commonly reported anecdotal side effect of starting low-carb diets.
If you're experiencing excessive and heavy bleeding on your period, visit your healthcare provider.
Breakthrough bleeding is a type of abnormal bleeding that some women might experience during pregnancy or in between periods. Unlike normal menstrual bleeding, breakthrough bleeding is not associated with a decrease in estrogen levels.
Breakthrough bleeding is associated with anovulatory cycles or cycles in which ovulation fails to occur. It is more commonly seen in teenagers and results when there is an insufficient level of luteinizing hormone. As a result, progesterone is not produced, and estrogen continues to stimulate the lining of the uterus. After a while, this proliferated lining might be shed out in an irregular manner resulting in “breakthrough bleeding”.18
So is breakthrough bleeding during the keto period a thing?
As a low-carb diet can alter the delicate hormonal balance, it is possible that it can induce breakthrough bleeding in some women. However, as with other menstrual irregularities, there is not sufficient evidence to support this claim. If you're experiencing irregular menstruation, it might be best to discontinue the diet for some time.
Low-carb diets are known for their effective weight loss effect. However, it should be kept that rapid weight loss can result in hormonal imbalance and menstrual problems in women. As keto induces a hormonal imbalance in some women, they might experience “spotting” between periods.
As there are other several possible causes of spotting or bleeding between periods, it might be best to seek professional advice. Visit your gynecologist or healthcare professional who might offer blood tests and investigations to determine the actual case.
Spotting or abnormal discharge of blood between periods is something women might encounter during their lifetime. The amount of blood is usually very scant and does not require the use of pads or tampons. There are several possible causes of spotting in between periods, one of them being hormonal imbalance.
There isn't a lot of available research that studies the link between keto and menstrual cycle abnormalities. However, given the fact that keto diets initially alter the hormonal balance, some women might potentially experience brown spotting.
However, it should be kept in mind that there is no documented scientific evidence and reports of spotting with keto. The majority of cases are self-reported on internet forums and might be due to other underlying contributing factors.
It is always best to seek the advice of your health care professional when you're starting a new diet. Always seek professional help when you're experiencing any unusual symptoms after introducing the changes in your diet.
Polycystic ovarian syndrome (PCOS) affects about 4 to 20% of all women around the globe.19 It is a condition that is characterized by abnormal and irregular periods, facial hair, and acne. PCOS is also a leading cause of infertility.
When it comes to inducing periods in women with polycystic ovarian syndrome, the ketogenic diet has shown promising results. According to a study published in 2020, this popular low-carb diet was able to restore menstruation in women with PCOS. Therefore, it can be concluded that, at least in some cases, keto can induce periods in women with PCOS.20
The ketogenic diet is popular because of its weight loss effect. A study published in 2003 reported that 45% of females experienced irregular cycles, or amenorrhea, as a result of the keto diet.21
As this diet can mimic some phases of starvation and extreme weight loss as seen in female athletes, women can experience delayed periods on this diet. Female athletes often have a limited intake of carbohydrates, similar to the ketogenic diet, which might potentially be the cause of their period irregularities.22
During periods of caloric restriction or weight loss, the part of the brain which secretes gonadotropin-releasing hormone (GnRH) gets affected.23 GnRH is the hormone that stimulates the release of female sex hormones that regulate the menstrual cycle. As the brain is unable to properly secrete GnRH, the release of female hormones is also affected. So on keto, the menstrual cycle can experience some delay due to hormonal irregularities.
Rapid weight loss and dietary changes can be stressful to the body. The female reproductive cycle is particularly sensitive to changes in dietary intake and stress. Keto diets are known to induce weight loss and stress response. Therefore, following low-carb diets and resulting in weight loss can lead to functional hypothalamic amenorrhea or absent menses in some women.24
If you notice that you have completely stopped having periods on the ketogenic diet, consult your gynecologist. You might also want to consider stopping the keto diet to see if it helps.
Any bleeding that occurs after more than 12 months of the last period is called “postmenopausal bleeding.”
It's very common for women to experience postmenopausal bleeding after they start hormone-replacement therapy. However, if the bleeding continues, it is important to get it checked as postmenopausal bleeding could be due to a more sinister cause. Some possible causes can include atrophic changes, polyps, and even cancer.
When it comes to the link between low-carb diets and postmenopausal bleeding, there is a lack of conclusive evidence that could establish it as a possible cause.
However, there are certain diets such as soy products that have been linked with postmenopausal bleeding due to their phytoestrogen component.25
While postmenopausal bleeding on keto is a possibility due to hormonal fluctuations, it is best to consult your OB-GYN. There are anecdotal reports of postmenopausal bleeding with keto, but there is no substantial evidence to back up this claim.
Period cramps can be very uncomfortable and might be experienced by some women when they start a keto diet. The bad period cramps might have something to do with the high-fat content of the diet.
According to one study, women with dysmenorrhoea experienced an improvement in their symptoms when they switched to low-fat diets. In addition, there is evidence in the literature that women with dysmenorrhoea usually have a high dietary fat intake. The intake of high fat is linked to "endometriosis" which is a disorder characterized by painful periods.26-28
If you're experiencing bad period pains, you can take ibuprofen to help with the symptoms. If the symptoms persist and are severe, seek the advice of your healthcare professional.
PMS or premenstrual syndrome refers to a group of symptoms that women might experience one or two weeks before their period. Some of the common symptoms of PMS include irritability, depression, fatigue, headaches, and bloating. While it is not fully understood why women might experience PMS, hormonal imbalances might be the possible cause.
A study published in Japan in 2004 reported the effect of high fat intake in exacerbating premenstrual syndrome symptoms.29 According to the research, women who had higher fat intake experienced the worst symptoms of PMS.
As keto diets are high in fat content, they can potentially exacerbate PMS symptoms. Another study reported improvement in the symptoms of PMS with the intake of whole grain foods.30
When on keto, period cravings can be an uncomfortable experience. This is because ketogenic diets limit carbohydrate intake to less than 50 g per day. This might be unsustainable during the premenstrual phase as women might naturally crave more carbohydrates before and during their period.
Food cravings are a recognized part of PMS. According to a study published in the International Journal Of Nutrition And Metabolism, the majority of female students experienced an increased appetite immediately before their period.31 As the energy levels drop during this period, it might be a signal of the body to increase energy levels through food intake.
Another possible reason for cravings could be explained by the low levels of serotonin in the premenstrual period during PMS. Intake of carbohydrates can potentially boost serotonin levels, and that is why some women might naturally crave carbohydrate-rich foods.32-33
Because the ketogenic diets are limited in carbs, women might experience a more intense craving for carbs before their period. However, it is important to avoid processed and junk foods as they can worsen the symptoms of PMS.
Your period is regulated by a complex interplay of hormones which can be influenced by dietary changes and stress.
When it comes to the ketogenic diet, there isn't a lot of research available that can explain the different menstrual irregularities women might experience. There are a lot of anecdotal reports of menstrual irregularities such as spotting, heavy bleeding, and delayed periods with keto. So on keto, period problems are often reported.
It is possible that the weight loss effect associated with keto could be the possible culprit behind your period problems.
If you think that keto might be causing you to have adverse symptoms, it is best to discontinue the diet for some time and consult your OB-GYN. The relationship between keto and the menstrual cycle is complicated. Until more research is available, it is best to be on the lookout for any adverse effects you might experience when on the diet.
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