This can be compounded by the stress of coping with children, elderly parents and demanding jobs. The result? A nervous system in disarray, high levels of the stress hormone cortisol and reduced melatonin, the sleep hormone.

Take action: Regulate your nervous system to calm anxiety and reduce stress, which will help improve sleep. Eat breakfast within 30 to 45 minutes of waking up, making sure that it's rich in nutrients - try Greek yoghurt with berries or eggs on wholewheat toast.

Reduce your caffeine intake and aim to drink at least two litres of water a day. Go to bed at 9.30pm four nights a week to train your body to rest earlier. Remove your phone from the bedroom and try reading or writing a gratitude journal if you're not ready to sleep.

Reduced serotonin levels have also been linked with depression and anxiety or simply a lack of excitement about life. 

Take action: there are things you can do to activate more positive emotions. Exercise, being in nature and listening to or playing music can all stimulate the production of serotonin and feel-good endorphins. Even tackling small chores like sending an email can give you a sense of satisfaction and a dopamine hit. 

Being in good company, laughing or just stroking a pet are ways to stimulate the "love" hormone oxytocin. However, you don't always need to get rid of uncomfortable feelings. If you constantly try to side-step them, you can end up exhausted and feeding anxiety. Instead, acknowledge your feelings and give yourself permission to gently "be" with the experience.

Changing oestrogen, progesterone and testosterone levels can impact your energy, strength and ability to recover from exercise. However, improving your cardiovascular fitness and building lean muscle tissue can help you regulate your hormones.

Take action: work with each phase of your cycle to get the most from your exercise routine. When your period starts, oestrogen levels are at their lowest, and women can experience cramps and fatigue. Just going for a walk can be enough. During the follicular phase - days one to 14 - your energy levels may increase as oestrogen rises. 

Exercise may also help to boost "happy" hormones serotonin and dopamine, as well as testosterone and oestrogen. All this may find you feeling more ready to get active, - just take care not to overdo it. In the luteal phase (days 14 to 28), oestrogen and progesterone start to decline, affecting energy and mood, which can impact motivation. Try calming activities such as yoga or Pilates. For women in perimenopause and menopause, exercise might help you manage your blood sugar and moods, and strength training is crucial for healthy bones, which reduces the risk of bone and muscle loss.

During the perimenopause and menopause, when oestrogen levels drop, dry skin becomes a common problem as oestrogen helps skin retain water. Women may also experience thinning hair as the ratio of male to female hormones changes. 

This is because in the luteal phase progesterone is higher, which can lead to blood glucose levels becoming more unstable. When glucose levels drop, we want high-carbohydrate and sugary foods for a quick energy release.

Take action: opt for high-protein, high-fibre foods and healthy fats to help minimise PMS symptoms. When oestrogen rises before ovulation, increase your fibre intake - try foods like flaxseeds, greens or lentils. If you're hoping to get pregnant, include omega-3 fatty acids (but if you get these from oily fish, the NHS recommends a limit of two portions a week). 

In the latter part of your cycle, enjoy foods rich in magnesium (almonds, avocados) to support low energy. Post-menopause, protein is crucial for maintaining muscle mass.

Increased oestrogen and progesterone can cause constipation or bloating; and the prostaglandin hormones that lead the uterus to shed its lining during your period can lead to cramping or diarrhoea. In menopause, declining oestrogen may affect gut microbiome diversity.