Lost your period? You might want to rethink your new diet of green smoothies and salads.
Perhaps your digestion feels better off carbs. Or maybe you’ve been told that low-carb is the best way to treat your PCOS. Either way, a low-carb diet might be okay in the short-term but can become a real problem for periods in the long-term.
As an active woman, you need about 2100 calories per day. Are you reaching that? Your green smoothie gives you 200 calories, and your can of tuna plus half a sweet potato gives you about 250. So far, that’s only 450 calories, which is not even a quarter of what you need, and it’s already afternoon.
⚠️ Tip: Please don’t worry about actually counting calories. Aim for at least three full, solid meals per day—and you’ll be okay. If digestive problems prevent you from eating that much, then seek digestive treatment (see below).
Why low-calorie and low-carb diets stop menstruation
Too few calories trigger a starvation response in your hypothalamus that disrupts luteinizing hormone (LH) pulsatility and shuts down ovulation. Too little carbohydrate (but enough calories) does the same thing. Therefore, as a woman, you need more carbohydrate than a man. You also need plenty of protein and fat and micronutrients, but you cannot rely on them as your sole source of calories.
Signs you don’t eat enough carbohydrate:
- Under-active thyroid and elevated reverse T3
- Hair loss
- Amenorrhea (lack of periods)
Under-eating causes amenorrhea, and this is true even if you have a healthy body weight (BMI). Your hypothalamus cares less about body fat and more about whether you eat enough to keep up with your activity level. 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 executive decision to halt reproduction.
Starvation-induced amenorrhea was a beneficial adaptive strategy throughout all of human history because it prevented us from trying to make babies when there wasn’t enough food.
⚠️ Tip: Under-eating is a common cause of Functional Hypothalamic Amenorrhea (FHA).
⚠️ 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, your friend may eat even lower carb than you, and she’s fine. Your friend is different. She may have insulin resistance, and so is benefiting from a short term low-carb diet. Or she may be able to get away with fewer carbs because she has a different “ovarian set point” than you. For more information on ovarian set-point, please see Dr. Grazyna Jasienska’s book Fragile Wisdom.
Energy is the key to understanding ovarian function. ~ Dr. Grazyna Jasienska
What if you have PCOS?
Didn’t you read somewhere that carbohydrates are bad for PCOS? True, too many carbohydrates (especially fructose) are bad for insulin resistance, but insulin resistance and PCOS are not the same things.
First things first: How was your PCOS diagnosed? If it was by ultrasound alone, then you may not actually have PCOS. PCOS cannot be diagnosed by ultrasound (read The Surprising Truth About PCOS). It’s diagnosed by a blood test for androgens and insulin.
If you’re avoiding carbs because someone saw polycystic ovaries on ultrasound, you may be on the completely wrong track.
But if, on the other hand, you do have insulin-resistant PCOS (and not another type of PCOS), then Yes, you may need to reduce carbohydrate. More specifically, you need to quit sugar, which is the worst carb, because concentrated fructose causes insulin resistance and insulin-resistant PCOS. You may also want to reduce starch, but only until you bring your fasting insulin between 30-60 pmol/L (4-9 mIU/L).
What if you can’t digest carbs?
If you cannot digest carbs, it’s probably because you have small intestinal bacterial overgrowth (SIBO), which causes fermentation of FODMAPs in the small bowel.
⚠️ Tip: Rice and potatoes are not FODMAPS, so they are the easiest starches to digest.
Reducing carbs to relieve bloating is okay in the short-term, but it’s not a solution in the long-term. Why? Because you need carbohydrate to have periods, and you need FODMAPS to feed your intestinal bacteria.
The long-term solution is to fix SIBO with a two-month course of antimicrobial herbs and HCl digestive enzymes (taken after a meal). Please consult your local clinician for help, and keep going with treatment until you can eat all gentle-carbs without bloating.
How long will it take to get your period?
Once you’ve increased calories and starch, you should see a period within 3-4 months. If not, then it’s time to do more detective work. See Chapter 7 of my book for a full troubleshooting discussion of amenorrhea. And if you’re looking at the herbal medicine Vitex, please understand that it will not work until you also increase your food intake.
Do you have an eating disorder?
If you’re frightened by the idea of eating more, then you may need to consider if you have an eating disorder. Approach it with self-love and self-forgiveness, and reach out for help. Here are some places to start:
- 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)
Eating disorder is incredibly common. You’re not alone, and you need not feel ashamed. Ask for help.