Can the Keto Diet Affect Your Period?

Keto Diet Period

As most readers such as yourself know by now, the internet can either be a gold mine of accurate, relevant and/or timely information, or it can be a potential minefield of erroneous, misleading, and/or distorted information. This is especially true for anyone seeking guidance and answers to questions on personal health, especially as they relate to diet.

Therefore, if you were to search for an answer to this question, you shouldn’t be surprised to find that the response can be either “yes”, “no”, or “maybe”, meaning somewhere in-between. From all my research and experience “maybe” actually appears to be more accurate and makes the most sense. Here is why:

Weight Loss and Your Period

An indisputable fact is that a “normal” menstrual cycle can be affected by weight loss. Common menstrual irregularities, such as amenorrhea, dysmenorrhea, and PMS may be linked to sudden or extreme weight loss, or both1 2 3 4. Although the rapid weight loss experienced on the ketogenic diet can trigger an irregular period by throwing off the balance of hormones that impact ovulation, this effect does not appear to be exclusive to the ketogenic diet. Case in point, there may be strong evidence supporting the association between weight loss and a disruption in a woman’s menstrual cycle5, but the evidence linking this disruption with weight loss associated specifically with the ketogenic diet appears to be either lacking or very weak.

The Impact of Diet-Induced Stress

It is possible that, just as your body perceives any major change in your diet or in the weight loss resulting from ‘going Keto’, as a type of stress, this often manifests in its own set of hormonal issues. Among the potential hormonal changes associated with stress, is the release of corticotropin-releasing hormone (CRH). This release triggers increased cortisol levels and results in a sharp decrease in a key hormone that regulates ovulation, gonadotropin-releasing hormone (GnRH)6 7 8.

Does the low-carb, high-fat nature of the ketogenic diet have anything to do with my period?

Once again, the answer is closer to a ‘maybe’ than a straight ‘yes’ or ‘no’. There is much greater evidence that points to prolonged energy deprivation or restriction, and not carbohydrate deprivation or a high intake of dietary fat, as a disruption in a woman’s menstrual cycle.

Some experts point to the link between very low carbohydrate diets and changes in the levels of luteinizing hormone (LH), a hormone that contributes to regular ovulation, but these same experts admit that evidence of this link is very limited. At the other end of the spectrum, high levels of LH have been observed in overweight and obese women with PCOS, a condition commonly associated with menstrual disorders and infertility9 10. Research also demonstrates that the ketogenic diet may actually more than double the levels of leptin, another hormone which helps regulate reproductive functions11.

Evidence suggests that a higher intake of beneficial dietary fats, such as omega-3 fatty acids found in fatty fish, flaxseed meal, and chia, are associated with increased progesterone concentrations and an increased rate of ovulation12. On the flip-side, if your ketogenic diet derives a large percentage of its fat from trans-fats, such as hydrogenated oils that lurk in prepared and packaged food, you are at a much higher risk of a disruption in ovulation13. This underscores the importance of prioritizing healthy fats over unhealthy fats on your Keto Diet.

How can the ketogenic diet actually benefit my menstrual cycle?

If you’re one out of the ten women of childbearing age who have been diagnosed with polycystic ovarian syndrome, or PCOS, the very low carb nature of the ketogenic diet can help regulate the excess insulin levels associated with PCOS, blunting the levels of the hormones androgen and testosterone and boosting estrogen levels which helps to stimulate ovulation14 15 16.

Dietary Deficiencies and Your Period

Just as weight loss itself is strongly linked to changes in your regular menstrual cycle, nutritional deficiencies associated with weight loss diets appear to have an even greater impact on your menstrual cycle than weight loss itself:  

Energy Deficiency

A prolonged calorie deficiency, which frequently occurs on weight loss diets such as a ketogenic diet, appears to be, hands down, the single greatest contributor to the disruption of the normal menstrual cycle17. The resulting energy deficit, caused by a depletion in the energy stores associated with a sustained low calorie intake, can have a powerful impact on our body’s hormonal function–at least for a short term. This could be due to an evolutionary survival mechanism developed during times when food availability and supplies were low or nonexistent. Any available energy was spared for high-priority body functions, such as that of our brain, and the maintenance of reproduction function was secondary.

Vitamin and Mineral Deficiencies Associated With Menstrual Disorders

A number of specific nutrient deficiencies have been linked to the development of menstrual irregularities and disorders and include the following:

  • Vitamin B1 (Thiamin): A deficiency of this vitamin is characterized by fatigue, muscle cramps, various pains and a reduced tolerance to pain, all factors that could be associated with dysmenorrhea18.
  • Vitamin B5 (Pantothenic Acid): Plays a role in the manufacture of adrenal hormones and red blood cells. Decreased levels of B-5 can also negatively affect adrenal function19.
  • Vitamin B-6 (Pyridoxine): Is involved in the production of prostaglandin, a compound that affects uterine contractions. B-6 is also involved in the utilization of magnesium and has demonstrated a beneficial effect on emotional symptoms associated with PMS. Low levels of Vitamin B-6 can contribute to cramps associated with dysmenorrhea20.
  • Vitamin D3: Low levels have been linked to a shorter length in your menstrual cycle21 22.
  • Calcium: Inadequate intake of this mineral is associated with increased risk of symptoms associated with PMS23.
  • Iron: Although a deficiency can result from abnormally heavy blood loss or prolonged heavy bleeding during your period, inadequate iron in the diet can worsen the anemia24.
  • Magnesium: Plays a key role in adrenal health and function, muscle relaxation and vasodilation25. Low levels of this mineral can exacerbate pain associated with your period and can lead to increased levels of stress and anxiety 26 27 28.
  • Zinc: Is involved in the production of hormones including estrogen and progesterone. A deficiency can inhibit levels of these hormones, compromising reproductive health29.
  • Omega 3 Fatty Acids (EPA and DHA): Low levels of these fatty acids have been linked to increased mood swings, anxiety, and symptoms of depression associated with a decreased transmission of two of our brain’s ‘mood-boosting’ chemical messengers, serotonin and dopamine30. For women with PCOS, omega-3 supplementation can reduce testosterone levels and regulate their menstrual cycle31. Supplementation with omega-3’s has also been shown to reduce pain associated with dysmenorrhea, as well as the symptoms of depression and anxiety associated with PMS32 33.

The Unique Role of Gut Health and Its Effect on Your Period

One of the principal regulators of circulating estrogen is the gut microbiome, the genetic material comprising the trillions of microorganisms in our body known as the microbiota. It has been known for decades that our overall health is directly linked to the health of our gut bacteria, but it has only recently been revealed that our gut microbiota is actually able to regulate estrogen through secretion of an enzyme known as β-glucuronidase. A lack of estrogen-metabolizing bacteria leads to a decrease in circulating estrogen and can lead to disorders such as endometriosis and PCOS34 35. Regardless of what diet you choose to be on, research shows it may be feasible to change the female ‘estrobolome’, the name given to the bacteria involved in estrogen metabolism, and reverse estrogen-related disorders by improving the quality of our diet36.

Suggestions and Possible Solutions to Help Get Your Period ‘Back on Track’

In the meantime, if you’ve been experiencing any form of menstrual irregularities while following ‘Keto’, the following are some suggestions that might help:

1. Do not under-eat calories.

The ketogenic diet, by its high-fat, moderate protein nature, has an appetite-suppressing effect which makes eating an adequate amount of calories more challenging. That’s where a little bit of ingenuity in meal prep can go a long way. Because fat itself is very calorie-dense you should use this to your advantage.

Starting with the first meal of the day, add fat, with greater emphasis on healthy fats, to everything you eat or drink whenever possible. One tablespoon of coconut oil/manna/butter/ghee, seed oil (i.e. olive oil, avocado oil), or MCT oil provides 100-120 calories. Most ‘fat-bombs’ have this same calorie range and are very easy to make. Start adding any of these to whatever you eat or drink and you will see how quickly the numbers on your ‘macro tracking app’ can add up to reach your goal! Be generous with other fat-dense food intake at meals or snacks, such as fatty fish (salmon, sardines), avocado, olives, nuts/seeds (including chia, coconut and flaxseed meal), and full-fat cheeses in addition to Greek yogurt made with whole milk.

Although ‘calorie counting’ on Keto is optional, an app that tracks your calorie intake could help ensure you don’t fall short.

2. Optimize the nutritional quality of your Keto Diet

Many health practitioners are quick to place the blame on the ‘poor nutritional value’ and very restrictive nature of the Keto Diet, which they say contributes to the menstrual irregularities. Suffice it to say the current Keto Diet, if done in a well-formulated way, puts an end to the #1 misconception that the ketogenic diet is either an inadequate or inferior diet. The consumer demand for gluten-free and/or low-carb versions of their carb-dense counterparts have made this diet not only more feasible and sustainable, but also bring a more than ample supply of nutrients to the table.

The following are just a sample of some new products and food hacks that are welcome kitchen staples for anyone on a Keto Diet:

  • Nut flours, such as almond and walnut flour, and coconut flour, are loaded with fiber and healthy fats and add to a wide variety of baked goods that one can either make on their own or buy at the ever-expanding space occupied by low-carb products at their local supermarket.
  • Unsweetened nut milks, such as almond and cashew milk, add flavor and variety to your meals and snacks and versatility to recipes, and are often enriched with a number of vitamins and minerals.
  • ‘Veggie’ versions of rice and pasta, such as riced cauliflower and ‘zoodles’ (made with zucchini) are great low carb hacks and help boost both the fiber and nutrient density of your meals. Put your ‘spiralizer’ and food processor to good use or buy ready-made versions of these products available at most supermarkets.
  • Assorted natural low carb sweeteners contain much improved taste profiles over their artificial counterparts and can satisfy your ‘sweet tooth’ without the guilt.

3. Maximize the impact of your microbiome

This includes consuming foods rich in prebiotic fibers that fuel our healthy bacteria, in addition to foods containing probiotics and probiotic supplementation.

4. Try nutritional supplementation

If you suspect that you or your diet might be deficient in any of the nutrients potentially associated with menstrual irregularities (see above), aim for boosting your intake of foods containing these nutrients and consider additional nutritional supplementation.

Key Takeaways

Whether or not the Ketogenic Diet can affect your period appears to have more to do with the rate of weight loss experienced on this diet and the adequacy of calorie intake on Keto. Research shows that a combination of dramatic weight loss and prolonged severe calorie restriction have a far greater impact on menstrual and reproductive health than any specific macronutrient shortfall, such as very low carbohydrate intake. There currently appears to be very limited evidence linking the ketogenic (very low carb, high fat) diet itself to an increased risk of menstrual disorders. However, a large body of research actually supports its use in the treatment of two common menstrual disorders: endometriosis and PCOS.

There also appears to be a potential ‘double-edge sword’ effect from the type of fat one might consume on the high-fat, ketogenic diet. While a high intake of processed (versus naturally-occurring) trans-fats has been shown to wreak havoc on your female hormones, omega-3 fats can have a healthy impact on these hormones.

The bottom line is that for anyone on a ketogenic diet seeking to minimize any issues with their period, it is essential to:

  1. Not skimp on calories
  2. Eat mostly healthy fats
  3. Boost intake of nutrient-dense foods, such as low-carb veggies
  4. Fuel your gut microbiota by making friends with fiber
  5. Don’t hesitate to supplement with key nutrients that you feel you might be missing out on.

Keep in mind that, even if your ketogenic diet may not be to blame, any irregularities associated with your period that intensify or don’t dissipate while on this diet can be a sign of a larger health issue.

  1. Functional hypothalamic amenorrhea and its influence on women’s health: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4207953/
  2. Nutritional and endocrine-metabolic aberrations in women with functional hypothalamic amenorrhea:  https://www.ncbi.nlm.nih.gov/pubmed/9435412
  3. Dysmenorrhea in adolescents and young adults: from pathophysiology to pharmacological treatments and management strategies : https://www.ncbi.nlm.nih.gov/pubmed/18803452
  4. Diagnosis and management of dysmenorrhoea  https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1459624/
  5. Menstrual cycle-related exacerbation of disease https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3107848/
  6. Effects of Low Energy Availability on Reproductive Functions and Their Underlying Neuroendocrine Mechanisms:  https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6068835/
  7. Caloric restriction: Impact upon pituitary function and reproduction: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2634963/
  8. Hypothalamic Hormones and Metabolism: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3244537/
  9. Insulin, somatotropic, and luteinizing hormone axes in lean and obese women with polycystic ovary syndrome: common and distinct features: https://www.ncbi.nlm.nih.gov/pubmed/8768842
  10. Inappropriate gonadotropin secretion in polycystic ovary syndrome: influence of adiposity: https://www.ncbi.nlm.nih.gov/pubmed/9360532
  11. (11) Leptin’s actions on the reproductive axis: perspectives and mechanisms: https://www.ncbi.nlm.nih.gov/pubmed/9915984
  12. Dietary fat intake and reproductive hormone concentrations and ovulation in regularly menstruating women:  https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4763493/
  13. Dietary fatty acid intakes and the risk of ovulatory infertility: https://www.ncbi.nlm.nih.gov/pubmed/17209201
  14. Ketogenic diet in endocrine disorders: Current perspectives: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5664869/
  15. (The Effect of Low Carbohydrate Diets on Fertility Hormones and Outcomes in Overweight and Obese Women: A Systematic Review: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5372867/
  16. Should the ketogenic diet be considered for enhancing fertility? https://www.ncbi.nlm.nih.gov/pubmed/23122539
  17. Regulation of gonadotropin secretion by monitoring energy availability: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5661764/
  18. Herbal and dietary therapies for primary and secondary dysmenorrhoea:  https://www.ncbi.nlm.nih.gov/pubmed/11687013/
  19. Pantothenic Acid: https://pubchem.ncbi.nlm.nih.gov/compound/vitamin%20B5#section=Top
  20. Pyridoxine (vitamin B6) and the premenstrual syndrome: a randomized crossover trial: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1711872/
  21. High dose vitamin D supplementation can improve menstrual problems, dysmenorrhea, and premenstrual syndrome in adolescents: https://www.ncbi.nlm.nih.gov/pubmed/29447494
  22. Low vitamin D status may affect menstrual cycle length in women: https://www.vitamindcouncil.org/low-vitamin-d-status-may-affect-menstrual-cycle-length-in-women/#.XEegoi2ZPBI
  23. Calcium and vitamin D intake and risk of incident premenstrual syndrome: https://www.ncbi.nlm.nih.gov/pubmed/15956003
  24. Iron out-of Balance in Women: http://www.irondisorders.org/women
  25. Magnesium in Prevention and Therapy: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4586582/
  26. Magnesium in the gynecological practice: a literature review: https://www.ncbi.nlm.nih.gov/pubmed/28392498
  27. Magnesium deficiency induces anxiety and HPA axis dysregulation: Modulation by therapeutic drug treatment: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3198864/
  28. Oral magnesium successfully relieves premenstrual mood changes: https://www.ncbi.nlm.nih.gov/pubmed/2067759
  29. The effect of low dose zinc supplementation to serum estrogen and progesterone levels in post-menopausal women: https://www.ncbi.nlm.nih.gov/pubmed/18759
  30. N-3 (Omega-3) Polyunsaturated Fatty Acids in the Pathophysiology and Treatment of Depression: Pre-clinical Evidence: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4115447/
  31. The effect of omega-3 supplementation on androgen profile and menstrual status in women with polycystic ovary syndrome: A randomized clinical trial:  https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3941370/
  32. The effect of omega 3 fatty acid supplementation on premenstrual syndrome and health-related quality of life: a randomized clinical trial: https://www.ncbi.nlm.nih.gov/pubmed/28707491
  33. Omega 3: Evaluation of the effect of omega-3 fatty acids in the treatment of premenstrual syndrome: “a pilot trial”:  https://www.ncbi.nlm.nih.gov/pubmed/23642943
  34. Microbial dysbiosis and disease pathogenesis of endometriosis, could there be a link? http://www.alliedacademies.org/articles/microbial-dysbiosis-and-disease-pathogenesis-of-endometriosis-could-therebe-a-link-6652.html
  35. (36) Association between Polycystic Ovary Syndrome and Gut Microbiota: https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0153196
  36. Estrogen-gut microbiome axis: Physiological and clinical implications: https://www.ncbi.nlm.nih.gov/pubmed/28778332
Mary Paley

Fearless Dietitian; 30+ years as a professional dietitian; Master’s Degree in Nutrition and Dietetics at the MGH Institute of Health Professions; Lead research dietitian for several major pharmaceutical companies; Currently focused on health and wellness and the benefits of ketogenic diets for both obesity and diabetes management. MS, RDN, CDE, LD/N

  1. So I have PCOS and the only way I would have my periods was on birth control which sucked because I am married and want to have a baby. So I would either be on birth control, have my periods but not be able to get pregnant or I would not be on birth control, not get my periods and still not be able to get pregnant. The last time I was on birth control was the middle of 2017. The end of 2018 I started the low carb high fat diet and within the first month I started my period. The next month of being on the diet I started my period again. Although I was beyond joy, I had still not gotten pregnant and in all honesty, this kinda thing takes time. I know my body was still trying to get back into the groove of things. But still I got discharged. I didn’t have a lot of motivation. I was missing eating bread and cakes and I started cheating on my diet more and more the third month and I didn’t get my period and haven’t had it since then. I just need the motivation to get back on. We don’t make a lot of money so it’s easier buying the cheap carb loaded food. My husband is really picky so he doesn’t eat what I eat on the diet. I’m trying to go back on the diet but again keep slipping up. I don’t have alternatives for sweets. I can’t afford to buy keto friendly chocolates and cookies and breads, etc.. that they sell online. I’m going to make it my goal though. I’m gonna get back on it. Wish me luck. Thank you for listening to me rant. ~Iyah

    1. Hi Iyah! Thank you for reaching out and describing your personal struggle with PCOS. I totally understand your frustration and dilemma. We’d love to chat further with you! Send us an e-mail at mary@fearlessketo.com so we can speak more in depth 🙂

Leave a Reply