“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.