Is There a Seasonal Trigger Behind Your Hot Flushes

hot flushes May 19, 2025

Did you know your menopausal symptoms may intensify with the change of seasons?

While scrolling through PubMed recently, a fascinating study caught my eye. It highlighted a connection I’ve long suspected from clinic experience but had never seen explored in the research: a seasonal rhythm to vasomotor symptoms like hot flushes and night sweats.

The study, titled Monthly variations of hot flushes, night sweats and trouble sleeping: Effect of season and proximity to the final menstrual period was published in the journal Menopause in 2020. It was part of the SWAN Menstrual Calendar Substudy—a 10-year observational project involving 955 women who tracked their cycles and symptoms through the menopausal transition.

What the Study Found

Originally, 3,302 women joined the study, but only those who had a natural menopause within that 10-year window and completed detailed symptom diaries were included in the final analysis.

Here’s what they found:

Hot flushes began 5–8 years before the final menstrual period in approximately 20% of women.
This increased to 48% four years out and peaked at 60% in the final year before menopause.
Night sweats followed a similar trajectory but were less common—starting at 30% and peaking at 40% in the final year.
Sleep issues were experienced by around 40% of women and remained relatively stable regardless of menopausal timing.

And now for the seasonal twist…

Seasonal Peaks in Symptoms

The researchers also found a significant spike in symptoms aligned with the North American summer months:

Hot flushes peaked in July (summer solstice), and were 70% more likely to occur compared to the winter months (January).
Night sweats peaked in June, with a 50% increased likelihood of occurrence.
Sleep disturbances peaked in July, with a 24% increase.

Take note: This was a North American study—so July equals summer. In the southern hemisphere (Australia, NZ), your symptom peaks may align more with January.

Why Does Summer Worsen Symptoms?

Women experiencing hot flushes and night sweats often have a narrower thermoneutral zone—this is the range in which your body feels comfortable and doesn’t need to heat up or cool down.

When your core temperature rises just slightly above this zone, you sweat.
When it falls just slightly below, you shiver.
Menopausal women can swing rapidly between the two—hence the classic jacket on, jacket off routine!

Certain factors narrow this thermoneutral zone even more:

Stress and anxiety (raise core body temperature via cortisol)
Declining oestrogen (reduces serotonin, which helps buffer temperature extremes)
Rapid external temperature changes (as seen in seasonal transitions or indoor/outdoor shifts)

On the flip side, serotonin helps widen the thermoneutral zone. But with falling oestrogen levels, serotonin often drops too—impacting not only thermoregulation but also mood, sleep, digestion, memory, and libido.

Seasonal Hormones: Melatonin vs Cortisol

The study also referenced earlier findings showing that:

Women in colder climates with greater seasonal variation in daylight and temperature were more likely to experience hot flushes.
This may be due to melatonin’s seasonal rhythm. In winter, longer nights = more melatonin production.
Melatonin supports sleep and buffers against stress by opposing cortisol.

In summer, less melatonin + more cortisol = increased vulnerability to stress-related temperature dysregulation—exactly the combination that worsens menopausal symptoms.

How Cellular Health Comes Into Play

Let’s connect this to your cellular resilience—because your ability to adapt to environmental stress, including heat and circadian disruption, starts at the cellular level:

🧬 Mitochondria, your energy-producing organelles, are key regulators of internal temperature and stress response. When under stress (like heat or inflammation), they can produce more reactive oxygen species (ROS), contributing to oxidative stress and symptom flares.
→ Support tip: Nutrients like CoQ10, magnesium, taurine, and B vitamins help stabilise mitochondrial output.

🕑 Circadian misalignment can increase cortisol and disrupt melatonin production.
→ Support tip: Prioritise light exposure in the morning, reduce artificial light at night, and maintain consistent sleep/wake times to restore rhythm.

💦 Hydration and electrolyte balance are critical for thermoregulation.
→ Support tip: Add a balanced electrolyte drink daily, especially during warmer months or after sweating. Consider molecular hydrogen water or structured water to enhance cellular hydration.

🌿 Polyphenols like resveratrol, quercetin, and pycnogenol can help buffer temperature sensitivity through antioxidant and anti-inflammatory effects.

What Can You Do About It?

Whether you're in the peak of summer or heading into it, now is the time to take action. Here’s how to start:

🧘‍♀️ 1. Lower Your Stress Load

Stress constricts your thermoneutral zone.
Daily practices like breathwork, yoga, nature walks, bodywork, and guided meditation can help.

🏊‍♀️ 2. Adjust Your Exercise

Regular movement improves serotonin and body temperature regulation.
Try water-based activities if heat or joint pain limits your options.

🌙 3. Optimise Your Sleep Environment

Keep your bedroom cool and dark.
Consider cooling bedding, a bedside fan, or an eye mask.
Try a nighttime routine with magnesium, taurine, or a melatonin-rich evening tea.

🧠 4. Strengthen Your Cellular Resilience

Focus on mitochondrial nutrients and hydration.
Try red light therapy, cold plunges, or vagal nerve stimulation to improve cellular stress response.

🩺 5. Seek Individualised Support

If you’ve been struggling with symptoms for years—or even months—it’s time to stop suffering in silence. This study showed 20% of women experience hot flushes 8 years before menopause. That’s far too long to wait things out.

Please reach out for help. I’m currently taking new patients and would be honoured to support your journey with a personalised, integrative approach.

[Book a Discovery Call]

Final Thoughts

There’s no denying that menopausal symptoms fluctuate—not just over years, but also across seasons. And while you can’t change the weather, you can take steps to strengthen your body’s ability to adapt to it.

Every action you take to support your stress response, circadian rhythm, hydration, and mitochondrial health will help widen your thermoneutral zone and reduce the frequency and intensity of symptoms like hot flushes and night sweats.

You are not meant to just endure this season of life—you are meant to thrive in it.