Lost your period? You might just need to eat more. A lot more.
Losing your period to under-eating is called hypothalamic amenorrhea and is common, particularly in women younger than 30.
You probably need at least 2100 calories per day just to maintain health. To recover from hypothalamic amenorrhea, you might need at least 2500.
Are you reaching that? Your green smoothie gave you 200 calories, and that can of tuna plus half a sweet potato gave you another 250. So far, that’s only 450 calories, which is not even a fifth of what you need.
How under-eating (and under-eating carbs) stops periods
Just how does under-eating stop periods? It’s simple.
Too few calories can cause the hormone command centre of the brain (the hypothalamus) to stop sending signals to the ovaries. It’s like turning off the “ovulation switch.” Too little carbohydrate (but enough calories) can do the same thing.
You can, therefore, lose your period to a low-carb or keto diet.
Signs you don’t eat enough carbohydrate:
- hair loss
- amenorrhea (lack of periods)
Under-eating can shut down ovulation, and that’s true even if you have a normal body weight (BMI). Your hypothalamus cares less about body fat and more about whether you eat enough to keep up with your level of activity. This is called energy availability and is the ratio between energy intake, body mass, and energy expenditure (exercise).
If you don’t eat enough, your hypothalamus thinks you’re in a famine and makes the very smart and adaptive decision to not try to make a baby.
👉 Tip: Hormonal birth control doesn’t solve the problem of amenorrhea because pill-bleeds are not periods.
Not every woman is the same. For example, older women are less likely to develop hypothalamic amenorrhea. Women with insulin resistance can actually benefit from a low-carb diet. And some women can simply get away with fewer carbs because they have a different “ovarian set point.”
Carbohydrate may be more important for women descended from agrarian ancestors. In her book Fragile Wisdom, evolutionary biologist Grazyna Jasienska builds the case that the hypothalamic-pituitary-ovarian (HPO) axis is calibrated to relatively recent ancestry. She calls it “ovarian set point,” which she defines as the ability to ovulate given a particular energy availability.
Energy is the key to understanding ovarian function. ~ Dr. Grazyna Jasienska
What if you have PCOS?
But what if you have PCOS? Shouldn’t you be avoiding carbohydrates in that situation? Possibly, if you have the insulin-resistant type of PCOS. But not if you have a different type of PCOS or if you have hypothalamic amenorrhea that has been misdiagnosed as PCOS.
Are you certain you have PCOS? How was it diagnosed? PCOS cannot be diagnosed by ultrasound.
If you’re avoiding carbs because someone saw polycystic ovaries on ultrasound, you could be on the completely wrong track.
If you’re certain you have insulin-resistant PCOS (and not another kind of PCOS), then yes, you may need to reduce carbohydrate. But first, you need to quit sugar because high-dose fructose is the main driver of insulin resistance. You may not need to avoid starch.
What if you can’t digest carbs?
What if you’re avoiding carbs not because you have insulin resistance or PCOS, but because you cannot digest carbs? If your digestion is better off carbs, then it’s probably because you have small intestinal bacterial overgrowth (SIBO). The solution is not to avoid carbs, but to fix SIBO!
👉 Tip: Rice and potatoes are easier to digest than FODMAP carbohydrates such as wheat.
One way to fix SIBO is with a two-month course of antimicrobial herbs and HCl digestive enzymes (taken after a meal).
How long will it take to get your period?
Once you’ve increased calories and starch, you should get a period within six months. If not, you’ll need a bit more detective work and troubleshooting. See Chapter 7 of Period Repair Manual for a list of questions for your doctor.
Do you have an eating disorder?
If you’re frightened by the idea of eating more, please consider whether you have an eating disorder. Approach it with self-love and self-forgiveness, and know that you’re not alone. Eating disorders are incredibly common and nothing to be ashamed of.
Reach out for help.
- Office on Women’s Health—Eating Disorders (USA)
- NHS—Eating Disorders (UK)
- National Eating Disorders Collaboration (NEDC) (Australia)
- National Eating Disorder Information Centre (NEDIC) (Canada)