There are two things that are common to most women: they have periods, and they’ve been on a diet at some point in their lives.
If there’s one thing I hope to change with my blog, it’s that second part of the above statement. I hate diets, I think they’re harmful, and I wish I could make the diet industry crash and burn (or at least make their tactics illegal because they’re that dangerous.)
I’m anti-diet for lots of reasons, including the havoc they wreak on our spiritual, psycho-emotional, physical and social health. However, they are particularly detrimental to one area of physical health for women, and that’s in terms of reproductive health. That’s because the effects of dieting on fertility (which isn’t just about pregnancy) are often less obvious than conditions like PCOS or endometriosis. However, they’re no less serious or significant. Even worse, healthcare providers rarely ask about the diet habits of their patients. And when they do, they often take answers like “I eat healthy” as a good sign. But there can be so many nuances interwoven in a response like that, and for me, it prompts so many follow-up questions that often leave patients feeling startled. Questions like:
- “What do you mean by that?”
- “Do you adhere to a specific diet? Are there foods you restrict?”
- “Do you feel that food dominates your life?”
- “Do you ever eat in secret?”
- “How okay are you with gaining two pounds?“
If you’ve been around my blog for any length of time, you know how I feel about the term “healthy eating” and that I see it as a red flag because so many women believe they’re doing something good for their health by dieting and are inadvertently harming themselves.
When it comes to the health effects of dieting, reproductive function is one of the first systems of the body to be affected. That’s why we sometimes refer to it as “the fifth vital sign” because it’s one of those functions that isn’t possible unless a patient truly is “fit and well.” (And I mean the true sense of the word fit…not “I’m so fit and workout so much that I don’t have a period.”) Dieting can cause or exacerbate everything from ovulatory dysfunction to sex hormone imbalances to period cramps, and while the diagnosis is simple, the solution doesn’t always seem that way. So, lets clear up some of that muddiness.

1. Hypothalamic Amenorrhea
Whenever we aren’t taking in enough energy, our bodies interpret this to mean that there isn’t enough food available to us—regardless of whether or not this is actually true. Periods of poor food accessibility are not a great time, from an evolutionary perspective, to bring new life into the world, and our bodies know this. If there isn’t enough food for one person, why add another and have two people without enough food?
The thing about menstrual cycles is that they’re also pretty expensive from an energy and resources standpoint. We literally lose blood and vital nutrients every month, and it takes a lot of energy and calories to build up the menstrual lining. Additionally, our basal body temperature raises nearly a whole degree after ovulation, which actually requires a lot of heat (energy) to sustain. Considering that it takes 1 calorie to heat 1 gram of water by 1 degree C….I’ll let you do that math.
Regardless of the numbers, menstruation is an energy-expensive process, and pregnancy would be even more expensive. So, our bodies shut them off. This is also true during other types of extreme stress, including excessive exercise (the kind encouraged by most fitness plans), psycho-emotional stress (such as the kind caused by meticulously following a diet plan and restricting tasty foods), and the sense of guilty and shame that result from difficulty complying with said diet plans.
Another important thing to keep in mind about hypothalamic amenorrhea (the absence of a menstrual period due to stress, energy deficits, exercise, etc.) is that a person doesn’t need to look emaciated in order for this to happen to them. In fact, it can (and often does) happen to women of a seemingly “normal” weight. Please note that I use that phrase in quotation marks because thanks to the media, many of us have a distorted idea of what a normal weight for a healthy woman even is.
Oh, and in case it isn’t already obvious, not getting your period is not normal.
2. Inflammation
I talk more about the concept of inflammation in a post from last week (click here to read) but here’s a quick refresher:
Whenever we have a localized area of inflammation, we have pain. This pain can vary in intensity, but in general, the higher the level of inflammation, the worse the pain is. The uterine lining naturally contains inflammation-causing chemicals called prostaglandins. This is a good thing because the prostaglandins are what trigger the shedding of the uterine lining during the cycle. Unfortunately, they also cause inflammation and pain. In a normal, healthy cycle, this pain is minimal, and feels like a mild ache, sort of like a sore muscle. But when there’s a lot of widespread inflammation in the body as a whole, there’s also a lot more inflammation in the pelvis during menstruation. The higher the level of inflammation, the worse the pain is.

Dieting creates inflammation in a number of ways. First of all, it creates a stress response in the body, which directly translates into increased inflammation. Second, restrictive diets often create nutrient deficiencies, and not having enough of important vitamins and minerals like magnesium, electrolytes, omega-3’s and other healthy fats increases oxidative stress in the body and creates—you guessed it—inflammation. Since dieting creates inflammation and widespread inflammation worsens pain, yes…dieting can create or worsen painful periods.
3. Progesterone Deficiency
Another problem with stress is that it suppresses the body’s ability to produce progesterone, which is a hormone that women need in order to be healthy. If ovulation is shut off completely, progesterone is way, way low, but even if your cycle doesn’t completely disappear, you can still suffer from low progesterone.
Symptoms of low progesterone vary from woman to woman, but they often include things like:
- breast tenderness
- spotting between or before periods
- fatigue
- weight gain
- depression or anxiety
- low libido
- headaches or migraines
- low blood sugar
- problems conceiving or staying pregnant
- …more!
As if those symptoms aren’t bad enough, there are also quite a few long-term health consequences of low progesterone, which I outline more in this post about progesterone deficiency.
The most common reason for low progesterone is stress. Stress can come in many forms, including nutritional stress (like not eating enough), physical stress (like exercising too much), and psycho-emotional stress (like the kind that results from trying to follow an extremely restrictive diet plan.) The main stress hormone, cortisol, is produced from the same precursor molecule that progesterone is produced from—pregnenolone. If we only have 10 molecules of pregnenolone in our bodies, for example, and 9 of those 10 are being funneled into the production of cortisol because we’re stressed to the max, there isn’t much left over to be converted into progesterone.

To sum things up…
Dieting harms our reproductive health in many ways, and this post covers just three of them. But more importantly, if you’re struggling with painful periods, spotting, or any other symptom, it’s extremely important that you discuss your concerns with a licensed healthcare provider. There are many factors that could be at play, and you deserve to be heard and cared for in the very best possible way.
That being said, if you’re experiencing the above symptoms (or any other new symptoms) and you’ve recently started a new diet, there’s a strong likelihood that the diet is contributing…at least in part. The best thing that you can do for your health is to ditch the diet and start taking care of your body in a gentle way. Checkout my kickstart guide, Foundations, if you need help getting started.