Why Do Women Experience Brain Fog and Memory Issues in Perimenopause?
By Dr. Simone Sturm
One of the most common concerns women share with me during perimenopause is: “Why can’t I think clearly anymore?” Many describe it as brain fog, forgetfulness, or difficulty concentrating. While frustrating, these changes are not “all in your head”—they have a true physiological basis.
The Physiology of Brain Fog in Perimenopause
Perimenopause is the transitional phase leading up to menopause, often starting in the 40s, though it can begin earlier. During this time, the levels of estrogen and progesterone fluctuate unpredictably. These hormonal shifts impact brain function in several key ways:
Estrogen and Neurotransmitters: Estrogen plays an important role in regulating neurotransmitters like serotonin, dopamine, and acetylcholine—all critical for memory, focus, and mood. As estrogen declines, these neurotransmitters can become dysregulated, making it harder to think clearly and remember details (why did I walk into this room?).
Sleep Disruption: Hormonal changes often cause night sweats, hot flashes, or insomnia. Without quality sleep, the brain cannot consolidate memories effectively, leading to forgetfulness and fogginess during the day.
Cortisol and Stress: Fluctuating hormones also interact with the stress hormone cortisol. Elevated or irregular cortisol levels can impair the hippocampus, the part of the brain involved in memory formation.
Blood Sugar Swings: Perimenopause can alter how the body processes glucose. Since the brain relies on glucose for energy, unstable blood sugar may contribute to mental fatigue and poor focus.
In short, the brain is working under fluctuating conditions—hormonal, metabolic, and stress-related—that directly impact clarity and memory.
Top 5 Holistic & Lifestyle Recommendations for Brain Fog in Perimenopause
Prioritize Sleep Hygiene:
Create a calming nighttime routine, limit screen time before bed, and keep your bedroom cool and dark. Consider relaxation practices such as meditation or herbal teas like chamomile or passionflower to improve sleep quality.
Balance Blood Sugar:
Eat balanced meals with protein, healthy fats, and fiber to avoid glucose spikes and crashes. This steadies energy levels and keeps the brain fueled consistently.
Support Brain Health with Nutrition:
Omega-3 fatty acids (found in fish, flax, and chia seeds), antioxidant-rich berries, and leafy greens support brain function and reduce inflammation that can worsen brain fog.
Manage Stress:
Incorporate practices like yoga, breathwork, or mindfulness meditation. These not only lower cortisol but also improve cognitive resilience and emotional balance.
Stay Physically Active:
Exercise boosts circulation, delivering more oxygen and nutrients to the brain. Activities like walking, swimming, or strength training also support hormone balance and mood.
Will I need bioidentical hormone replacement therapy?
For some women, bioidentical hormone replacement therapy (BHRT) may also be an important part of treatment, especially when symptoms are significantly disrupting daily life und functioning. BHRT can help stabilize hormones and reduce brain fog, but it works best when combined with the holistic lifestyle recommendations highlighted above. By pairing hormone therapy with strong foundations in sleep, nutrition, stress management, and movement, women can experience the most sustainable improvements in both cognitive clarity and overall wellbeing.
Final Thoughts
Brain fog in perimenopause is common—but it is not inevitable. By understanding the underlying physiology and making supportive lifestyle shifts, women can reclaim mental clarity and focus during this transition. At Denver Holistic Medicine, I work with women to create individualized plans that address both the root causes and daily challenges of perimenopause.
Remember: your brain is resilient. With the right support, you can thrive in this next chapter of life.
If these ideas resonate with you, book a consultation so we can tailor a plan—nutritional, supplement, or lifestyle—that aligns with your unique hormone profile. Your body is listening, and change is possible.