My Period Is Changing
Is Fasting Impacting My Period? Why quitting fasting might be the solution to your hormonal “imbalance”
Written by Dr. Fiona Callender, ND
Undereating - or more specifically, having low energy availability - is interpreted by our brains as a stressor. This is one of the more common factors leading to hypothalamic amenorrhea - the loss of our period due to hormonal control at the level of the brain. A major factor in hypothalamic amenorrhea is low estrogen (hypoestrogenemia) - an early manifestation of which is shortening (or lengthening) menstrual cycles. We don’t need to fully lose our period to be impacted by this shift in hormones!
Changes to our menstrual cycle can spark some concern for many of us and this is a common reason young women end up in my office. Menstrual cycle changes require a thorough assessment - we go through their routine, lifestyle, family history, medication use, then we talk about diet and exercise. We might recommend lab work or go through labs they have already done. With ruling out other conditions, it is not uncommon for us to land on a discussion about how our bodies interpret stress and how this may be impacting our cycle.
Our brain responds to the changing environment in and around our body
Through various neural, chemical and hormonal communications, our brain senses and responds to “stressors”. The big players impacting the menstrual cycle include psychological stress, low energy availability and intense exercise. When the brain senses high energy demands or lack of fuel - or time of unrest or scarcity - it responds by slowing pulses of the hormone GNRH (gonadotropin releasing hormone). When the pulses of GNRH slow, our other brain hormones - FSH and LH also decrease. Without these hormones in high amounts, our ovaries aren’t stimulated to produce estrogen. Without estrogen, we don’t have ovulation, we don’t build up a good uterine lining and, eventually, lose our period. This lack of ovulation can manifest as shorter or longer cycles to start, it doesn’t necessarily disappear right away.
In times of stress, our body prioritizes essential bodily functions and attempts to pause high-energy non-essential tasks - such as growing a baby. This makes sense as the menstrual cycle (and growing a fetus) are incredibly energy intensive processes!
I’m not losing weight, It can’t be my diet
Each of our bodies may have a different threshold or experience of stress and it depends how our brain interprets these changes. It is often shocking for patients when I explain that even though they aren’t trying to lose weight, the amount they are eating, combined with their exercise routine, is likely a factor in their shifting menstrual cycle. Layer on chronic stress or major life changes - we have some factors to address!
What is low energy availability?
Low energy availability is essentially how much energy is leftover from the food we eat for bodily functions, after we subtract the amount used in exercise. Simply existing requires energy, as well as any movement or exercise we add in on top of this! There is some research to suggest that having a drop in about 300kcal of energy in a day is enough to impact energy availability. This is largely through a decrease in blood sugar availability to our brains - which results in a slowed release of that hormone GNRH. It doesn’t take a lot of restriction to impact our hormonal secretion - especially in very young women. Our teens are likely the most susceptible to these small dips in energy availability.
Although this is often experienced by those with restrictive eating patterns or eating disorders, it can also occur inadvertently in those who are very active. You don’t have to be trying to lose weight to experience an inadequate fuel intake for your needs! It is also not just a low body weight issue - though this is certainly a factor for many. Any shape or size of body can respond to low energy availability with a change in menstrual cycle.
Intense exercise itself may actually be an independent factor for period changes - though it’s often difficult to separate this from energy availability. It’s actually our avid exercisers, as opposed to our elite athletes, that seem to be even more impacted by exercise as an independent stress. This may be due to adaptation to exercise or thoughtfully planned exercise schedules in elite athletes compared to the average exerciser. Elite athletes go through phases of training where they are primed for competition - which may mean changes in body composition in some sports - but they don’t maintain this all year round. This is important to remember when thinking about our own goals - not only do we need rest built into training schedules, we also need to build gradually to adapt to our training. Aiming for a specific level of “leanness” all year round isn’t realistic or healthy either! Elite athletes shouldn’t have this goal, and neither should you.
But losing my period doesn’t bother me - what are the consequences?
Beyond the frustration of an irregular menstrual cycle, having prolonged periods of low estrogen can have far reaching impacts on our health, both short- and long-term.
Bone
Estrogen stimulates our bone building activity! When estrogen is decreased, bone production is suppressed. Low estrogen actually decreases our ability to absorb calcium from our digestive tract too - further impacting our bone density. This is especially concerning for young women who are in their peak bone-building years. Just 6 months of missing your period can have bones appearing like those of a woman in menopause. This puts you at higher risk of fracture and, down the road, significantly impacted quality of life.
Cardiovascular health
Estrogen is also important for the health of our blood vessels. We see this become a concern for those in menopause as we have an increased risk of cardiovascular events. There is research indicating that young women with menstrual irregularities (and lowered estrogen levels) are at increased risk of future cardiovascular events - up to 50% increased risk! This is something we want to assess and manage early.
Mental health
Our mood and menstrual cycle appear to have a bi-directional impact on one another. We know that life stressors and perceived impact of these stressors can impact how our brain secretes hormones, but we also know that lowered estrogen states can impact mood. Low estrogen impacts our serotonin and dopamine production, impacting mood. Women with hypothalamic amenorrhea tend to have higher rates of depression and anxiety. We always address mood, mental health, stress and body image when we discuss these changes in the menstrual cycle. It is not uncommon for us to make referrals for additional support with a therapist. You deserve a well-rounded care team.
So what can we do?
We work together to understand what part of the puzzle requires some changes. Have we recently taken up a new exercise routine and haven’t been fueling our body enough to keep up? Have we gone through a period of emotional stress or high demand at work? Are we trying to lose weight for our wedding and heard fasting is the way to “balance blood sugar?”
We gain understanding about where you are at and go from there. Everyone will be a little different but we do have a few key points that will be important for everyone:
My number one rule is absolutely no fasting. Because of the pulsatile nature of our hormones impacting the menstrual cycle - GNRH pulses every 1-6 hours depending on the person and phase of menstrual cycle - we don’t want to skip meals. We want to send signals of abundance, not scarcity, to our brains! Studies have shown that it’s not only the total amount of calories that are delivered, but also the distribution of those calories that is important for normal hormone production. Hourly deficits in energy availability can result in higher cortisol and lower thyroid function - impacting our metabolism and hormones! Regular meals and snacks are your friend.
We all need a balance of macronutrients - carbohydrates, fats and protein. They all have an important role to play in our health. Skipping out on any of them is a no-go when getting our cycle on track. Our brain is actually sensitive to changes in fuel storage and availability. Stored carbohydrates (in the form of glycogen) are especially important - and also one of the first macronutrients that people tend to restrict.
I almost always talk about stress management. For many - especially for those who experience hypothalamic amenorrhea - exercise is a form of stress relief. We do everything we can not to have to cut back on exercise too much. We discuss optimal fueling and how to manage stress in other ways. We keep your exercise or sport (for most people) even if that means having to adapt.
Ultimately, we work together to understand why your cycle might have changed and come up with a plan to get it back on track. If you are curious if a naturopath is the right practitioner for you, we always recommend booking a complimentary meet and greet to ask your questions and discuss next steps.