The Menstrual Phase
For decades, the menstrual cycle has been viewed through the narrow lens of reproduction. Fortunately, a surge in research over the past few decades has broadened our perspective, revealing the profound impact this complex, hormonally-regulated process has on our overall health.
In Canada, this is in part due to the strides being made in women’s health research thanks to programs like the $20-million National Women’s Health Research Initiative (NWHRI). This initiative focuses on gender-diverse health, aims to reduce gaps in care, and invests in research for diseases affecting women. This renewed focus signals a brighter, more informed future for women’s health.
As we learn more, we see a powerful opportunity to work with our bodies. By understanding our hormonal fluctuations, we can tailor our diet and lifestyle to feel our best throughout the cycle.
Menstrual Cycle Complexities
A typical menstrual cycle occurs every 21-35 days and is regulated by a complex interplay of hormones, primarily estrogen and progesterone. Fluctuations in estrogen and progesterone may influence energy metabolism, appetite regulation, gastrointestinal motility, inflammation, mood, and sleep. As a result, many notice changes in hunger, cravings, digestion, physical training tolerance, and menstrual symptoms across the month.
While textbooks often describe a “standard” cycle, it is important to note that symptoms, appetite, digestion, mood, and energy levels vary widely between individuals and even from cycle to cycle in the same person.
What is Cycle Syncing?
By understanding these individual fluctuations and how they impact well-being, it’s possible to align activities, nutrition, and exercise with the menstrual cycle, a concept known as cycle syncing.
While this practice has grown in popularity, most current recommendations are based on physiology, observational data, and personal experience. Although some small studies support its efficacy, larger randomized controlled trials are still needed to confirm its benefits. For this reason, the most effective approach is to focus on your individual patterns and symptoms, use cycle and symptom tracking as a tool, and prioritize overall diet quality.
Eating for your Menstrual Cycle
Seed Cycling
One practical avenue within the broader concept of cycle syncing is seed cycling. This strategy involves eating specific seeds during different phases of the menstrual cycle to support hormone balance. Although we’re still waiting on strong human evidence, the initial research is promising, particularly for those with PCOS (polycystic ovarian syndrome). It’s a gentle, low-risk way to support your body’s natural rhythms and add a healthy variety of nutrients to your diet.
Seed Cycling Phases
Split into Follicular (Days 1-14) and Luteal (Days 15-28).
- Follicular: Focus on seeds rich in zinc and lignans to support estrogen metabolism (e.g., flax seeds, pumpkin seeds).
- Luteal: Focus on seeds rich in vitamin E and selenium to support progesterone production (e.g., sunflower seeds, sesame seeds).
Eating for your menstrual cycle is about understanding your hormones and working with your body instead of against it. Each phase comes with natural changes in energy, strength, digestion, hunger, and mood, and your nutrition can help support these shifts. With small, intentional adjustments, it’s possible to improve PMS symptoms, support digestion, and boost energy.
Phase 1: Menstrual (Menses)
Can last between 2-8 days
The menstrual cycle begins with the menstrual phase, which marks the start of a new cycle. Understanding the physiological changes during these initial days is fundamental to supporting the body’s needs over the subsequent weeks. This phase establishes a baseline for the body’s rhythms, allowing nutrition and practices like seed cycling to offer targeted support.
Menstruation occurs when progesterone and estrogen fall, triggering the shedding of the uterine lining, resulting in menstrual bleeding. Estrogen and progesterone are at their lowest levels during this time. This process is mediated by prostaglandins that stimulate uterine contractions, which help shed the lining, resulting in menstrual bleeding. However, this can also affect smooth muscle in the gastrointestinal (GI) tract, explaining why some people may experience more cramping, diarrhea, or bowel changes during this phase.
Common symptoms during this phase include fatigue, cramps, bloating, lower appetite, lower motivation, lower iron levels, and headaches.
Nutrition Focus of the Menstrual Phase
Iron Status
Menstrual blood loss is a contributor to iron deficiency. While not everyone requires increased iron intake, those with heavy bleeding or low ferritin (iron stores) will benefit from prioritizing iron-rich foods like meat, poultry, fish, tofu, or spinach paired with vitamin C-rich foods like citrus fruits, strawberries, bell peppers, tomatoes, or leafy greens to assist in absorption.
Avoid consuming iron-rich foods with coffee, tea, or calcium-rich foods at the same sitting, as these can inhibit absorption. Speak with your Registered Dietitian if you follow a predominantly plant-based diet, want support with optimizing your iron status, or are considering starting an iron supplement.
Click here for a list of iron rich foods
Nourishing Your Body to Manage Symptoms
If you experience cramps and digestive issues, the right foods can make a world of difference. A diet rich in omega-3 fatty acids, antioxidants, and whole foods can be your best friend during this time. Focus on fatty fish like salmon, colourful fruits and vegetables, olive oil, nuts, and legumes.
Seed cycling during your period can help balance hormones and ease common symptoms. Flax and pumpkin seeds provide essential nutrients that may reduce cramping and bloating. The lignans in flaxseeds help regulate estrogen, while the magnesium and zinc in pumpkin seeds support muscle relaxation and overall wellbeing.
At the same time, it can be helpful to limit alcohol and excessive caffeine, as they can sometimes worsen cramps and disrupt sleep.
To support your gut through changes in bowel movements, try incorporating easy-to-digest meals with plenty of soluble fibre. Foods like oats, avocados, chia seeds, and sweet potatoes can be incredibly soothing. And, as always, staying hydrated is key to feeling your best.
What About Cravings?
Many people experience intense cravings for comfort foods (often those high in sugar, salt, or fat) in the days leading up to their period. This is not a lack of willpower, but a genuine physiological response.
Before a period starts, a drop in estrogen levels and a rise in cortisol (the stress hormone) can lead to a dip in serotonin levels. Serotonin is a neurotransmitter that contributes to feelings of well-being, and when its levels are low, the body may instinctively seek out quick fixes, like sugary or high-carb foods, to get a temporary boost. Research suggests that these hormonal fluctuations directly impact appetite and can lead to cravings for specific foods, especially those high in carbohydrates and fat.
Instead of fighting these urges, it can be helpful to work with them:
- Make smart swaps: A couple of squares of dark chocolate (70% or higher) can satisfy a sweet craving while providing magnesium and antioxidants, which may help ease cramps. It has even been shown to support pain management during menses.
- Don’t skip meals: Eating regular, balanced meals and snacks helps keep blood sugar stable. This can prevent intense cravings from taking over. Focus on meals that include protein, healthy fats, and complex carbs.
To help support this phase of your cycle, try this iron-rich, fibre packed recipe:
One-Pot Salmon, Spinach and Lentil Salad
This dish combines vitamin C from tomatoes and lemon to boost iron absorption, soluble fibre from lentils and avocados to support gut health, and omega-3 fatty acids from salmon.
Listen to your body
Navigating the ups and downs of your menstrual cycle is a deeply personal experience. Understanding these physiological processes allows you to move beyond rigid rules and develop a more intuitive, informed approach to your body’s needs.
The next part of this series will dive into the follicular and ovulatory phases. We’ll explore nutrition strategies and specific foods to support hormonal balance and optimize your well-being during the first half of your cycle.
