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When we think of the effect of hot weather on our bodies, our thoughts invariably go to breakouts and a fitful night's sleep. But did you know that our hormones are also thrown out of whack when temperatures rise?
According to Hannah Alderson, a nutritionist specialising in hormones, "we can become dehydrated, which affects the liver’s ability to metabolise and detoxify hormones like oestrogen. Hot weather impacts hormone balance because the body has to work harder to regulate its temperature.”
And a hormone imbalance can impact everything from our stress levels and menstrual cycle to bloating.
Aside from pressing your forehead against the freezer door, the overarching advice is to drink at least two litres of water a day (more if you're active) and consume water-rich foods to combat this perfect storm. “Essentially, your liver needs adequate water to function properly,” Hannah adds.
Experts reveal the key symptoms you need to know.
Ahead, we delve in more detail into the key ways a heatwave can affect your hormones - and explore a few handy coping strategies to help ease the side effects.
1.Increased cortisol levels
Hot temperatures can cause a spike in cortisol levels. Known as the body’s stress hormone, it is part of the body’s fight or flight response. We need cortisol to help regulate our blood sugar, control our sleep-wake cycle and boost tissue repair, but there's a tipping point and too much cortisol can lead to physical and emotional stress.
“When exposed to high temperatures, the body can experience a form of physical stress," says Dr Jennifer Singh, a general practitioner at The Marion Gluck Clinic, one of the UK's leading hormone-balancing clinics. “Heat stress”, and the body's attempt to regulate its internal temperature in response, falls into this category.
“Heat activates the hypothalamic pituitary adrenal (HPA) axis, resulting in the release of cortisol,” Dr Singh explains. "The body has to work harder to cool down by increasing heart rate, blood flow to the skin and sweating, and these physiological changes trigger stress responses resulting in cortisol release.”
Over time, too much cortisol and always being in high gear can have a detrimental effect on your mind and body. “Elevated cortisol levels over time can lead to issues like anxiety, fatigue and hormonal imbalances,” says Hannah.
Coping strategy: Keeping cool and staying hydrated is key to helping your body maintain its optimal temperature, says Dr Singh.
“When your body is well-hydrated, it can manage stress more effectively, which helps prevent spikes in cortisol,” adds Hannah. As well as drinking plenty of fluids, “lower your body temperature with fans, cool showers or air conditioning," she says. "Managing stress through relaxation techniques like deep breathing or meditation can help keep cortisol levels stable, too.”
Meanwhile, Dr Singh recommends “consuming foods rich in antioxidants, B vitamins and minerals like magnesium to help support the adrenal glands and alleviate cortisol spikes.”
2. More painful periods
There's a natural rise in internal body temperature when you're on your period. Factor in hot weather outside, and it's unsurprising that you may suffer from persistent headaches and tiredness – not to mention the discomfort of wearing a bulky sanitary pad.
“Heat and dehydration can also affect oestrogen and progesterone levels, leading to symptoms of hormonal imbalance," says Hannah. “This might mean irregular periods or worsened PMS symptoms, such as cramps.”
Coping strategy: “Your liver plays a key role in regulating oestrogen and progesterone, and without enough hydration, it can struggle, leading to bloating and mood swings," Hannah explains.
To ease symptoms, she advises increasing your water intake and snacking on hydrating foods, such as cucumbers, watermelon, and strawberries. Other additions you could add to your routine, says Hannah, include "herbal teas, such as spearmint tea, which is also good for PCOS [polycystic ovary syndrome].”
3. Weaker immune system
We don't tend to think of hormones as being vital for a well-functioning immune system. But hormones actually play an intricate role in how well we fight off infection.
Oestrogen is thought to regulate the immune system but "heat and dehydration can weaken it by affecting the balance of hormones like cortisol and oestrogen, making you more vulnerable to illness,” Hannah says.
Likewise, thyroid hormones, which play a crucial role in immune function, can be decreased by heat, notes Dr Singh. Heat can also influence the release of molecules called cytokines that can cause inflammation, she adds.
At first, “the body produces heat shock proteins that help protect cells from damage,” explains Dr Singh. “However, elevated cortisol due to the heat can suppress the immune response, reducing the body’s ability to fight infections.”
Coping strategy: “Supporting your body's immune function in hot weather means staying hydrated to help regulate cortisol levels and support liver health,” says Hannah. Important, too, is eating a balanced, nutrient-rich diet, especially one featuring a serving of protein with each meal.
Without sufficient protein, your body might struggle to produce enough immune cells and antibodies to fight off illness, says nutritionist Riya Lakhani-Kanji. While Dr Singh advises including foods rich in vitamins C and E, zinc and omega 3, as well as "probiotic foods to help maintain gut health, which is closely linked to the immune system.”
4. Feeling exhausted, sore breasts and bloating
“Dehydration during a heatwave can lead to poor liver function, which can cause an accumulation of excess hormones like oestrogen,” says Hannah. “This might result in symptoms such as fatigue, bloating and sore breasts.”
Coping strategy: “Cold herbal teas, like green tea, not only help with hydration but also offer specific hormonal benefits, such as supporting metabolism,” says Hannah.
5. Poor sleep
It may seem obvious, but hot weather can disrupt your sleep. Aside from an overly hot bedroom that can leave you tossing and turning, “heat exposure at night can also disrupt melatonin production, leading to poor quality sleep," Dr Singh notes. This, in turn, "can impact cortisol levels and growth hormones,” which are essential for tissue repair and regulating our metabolism.
Coping strategy: Adequate rest is important if you want to avoid higher cortisol levels, says Dr Singh.
If you're getting stressed because the heat is interfering with a good night's sleep, try the fan and ice hack before bed. Put some ice in a bowl and place it in front of a fan. As the air passes over the ice, it picks up the moisture and circulates a chilly mist across the room.
Genius tips to help you drift off when it's hot and muggy.
6. You feel happier
However, it's not all doom and gloom. A silver lining is that in hot weather, we're also likely to be soaking up more vitamin D - a.k.a, the ‘sunshine vitamin’.
According to Rhian Stephenson, nutritionist, naturopath and founder of Artah, 90% of absorbable vitamin D comes from sunlight, as a result of UVB rays interacting with a protein in the skin and converting it into vitamin D3.
She believes it's so essential to our wellbeing, and plays such a crucial role in our bodies' hormonal processes, that we should “think of vitamin D less as a vitamin, and more as a pro-hormone," she says.
Then there's the boost in mood that comes with a sunny day. “Improved vitamin D levels help the brain to make feel-good chemicals like serotonin, which can make you feel happier,” says Hannah.
For more from Fiona Embleton, GLAMOUR's Associate Beauty Director, follow her on @fiembleton.
