Hormones
How your monthly cycle affects everyday life
Hormones are chemical messengers that help different parts of your body talk to each other. Across the menstrual cycle, hormone levels rise and fall in a predictable pattern. These changes influence mood, energy, sleep, appetite, focus and how your body handles stress and blood sugar. When you understand this rhythm, symptoms stop feeling random or like a personal failing — they start to make sense.
What this feels like in real life
• Feeling more confident, chatty or capable one week, then suddenly more tired or emotional another
• Wondering why your motivation disappears even though “nothing has changed”
• Feeling frustrated with your body for not being consistent
The two main hormones
Oestrogen rises in the first half of the cycle (from your period to ovulation). It supports motivation, confidence, memory and emotional balance by increasing the activity of brain chemicals like serotonin and dopamine, which help regulate mood and focus (National Institute of Mental Health, 2022: https://www.nimh.nih.gov/health/topics/depression). Research in neuroendocrinology has shown this relationship consistently over the last two decades (Endocrine Reviews, 2015: https://academic.oup.com/edrv).
Many women notice that as oestrogen rises, they feel clearer-headed, more social and more capable. Tasks feel easier, conversations flow more naturally and confidence tends to increase. This is not a mindset shift — it is real biological support for your brain.
What this feels like in real life
• Getting through your to‑do list with less effort
• Feeling more like yourself and less self‑critical
• Having more patience with other people
Progesterone becomes dominant after ovulation. One of its breakdown products interacts with the brain’s calming system (the GABA system), which can promote relaxation and sleepiness (Nature Reviews Endocrinology, 2018: https://www.nature.com/nrendo). Some women feel calmer during this phase, while others feel more sensitive, anxious or emotionally reactive. Both responses are normal and depend on how your brain responds to progesterone.
What this feels like in real life
• Wanting quieter evenings and more alone time
• Feeling more easily overwhelmed or tearful
• Needing more reassurance or emotional safety
Why symptoms often appear before a period
In the days before menstruation, both oestrogen and progesterone fall sharply. This drop affects brain chemistry, sleep regulation and energy production. Large population studies show this hormonal withdrawal is linked to premenstrual mood changes, lower concentration and increased fatigue (American College of Obstetricians and Gynecologists, 2020: https://www.acog.org).
What this feels like in real life
• Irritability over small things
• Brain fog or forgetting words
• Feeling disconnected, flat or emotionally rawThis does not mean something is wrong with you — your body is transitioning into a low‑hormone phase.
Hormones and blood sugar
Hormones also influence how efficiently your body uses glucose (sugar for energy).
Research shows that insulin sensitivity is slightly lower in the second half of the cycle, meaning the body does not move sugar into cells as efficiently (Journal of Clinical Endocrinology & Metabolism, 2014: https://academic.oup.com/jcem).
What this feels like in real life
• Strong cravings, especially for carbs or sweets
• Energy crashes a few hours after eating
• Feeling shaky, irritable or unfocused if meals are delayed