Why you should always have sex at 10pm

...never have coffee before 9am and ask for a pay rise at noon. A new study reveals how to harness the power of your psychological clock...

EVER wondered why you feel miserable at 2pm, lazy at 3pm and happy at 8pm? Scientists are discovering that our moods follow amazingly predictable daily patterns.

Two recent studies of more than 800 million tweets over four years discovered that people’s rising and falling moods — as revealed by the words they chose — almost exactly matched the daily patterns of two key chemicals in the body: the stress hormone cortisol and the ‘happy’ neurotransmitter serotonin.

It’s not just serotonin and cortisol that affect our mood: blood sugar levels, nutrition, and the ebb and flow of other hormones and chemicals also contribute to our psychological body clock.

‘It’s a mix of factors all working together and it’s difficult to disentangle them,’ says Daniel Pink, who researched daily rhythms for his book, When — The Science of Timing (€28, Canongate).

‘What’s certain is that our mood and cognitive abilities don’t stay the same throughout the day. They change in predictable and sometimes extreme ways. There’s a right time to do everything.’

So here’s how to make the most of your mood, every minute of every day . . .

6am

GET up! Your body has been producing cortisol for a couple of hours now. This is the hormone that kicks you into action; levels peak 30 minutes after we wake up and remain high in the first hour.

Getting up early, even if you don’t need to, is associated with lower rates of depression among women.

Try: Making lists. Our minds are at their sharpest now and we’re focused on personal goals, according to studies by Bristol University, making this the perfect time to concentrate on targets.

7am

TESTOSTERONE levels peak in women between now and 8am, and cortisol is still raised — which means our drive and motivation are sky high.

We’re also less angry, according to researchers who analysed 800 million messages posted on Twitter and found a strong correlation between the time of the day and negative and positive emotions. This makes it a good time to deal with a problem.

Try: Protein, nuts, seeds and fruit — and ditch the white toast. Eating just carbs for breakfast can cause a crash in your blood sugar levels, and hence your mood, mid morning, whereas adding protein keeps you fuller for longer, says women’s hormone expert Maryon Stewart (maryonstewart.com).

8am

HAVING got up in good spirits, our mood now takes a dive: studies show 8am is a peak moment for sadness and tiredness (worst on a Monday, no surprise there).

Try: A 30-minute walk outside to offset negativity. You need half an hour of daylight each morning to regulate your body clock: sunlight tells the brain to stop producing the sleep hormone melatonin. Twenty minutes of moderate exercise can impact your mood for 12 hours.

9am

POSITIVE emotions are on the rise. ‘Any morning grogginess has worn off because the cortisol has worked its magic, yet it’s early in the day so our brain is a clean slate,’ says Pink. Serotonin levels are also increasing — until 11am.

‘Something definitely happens around 9am and positive emotions become dominant,’ says Dr Fabon Dzogang, who worked on the Twitter studies.

Try: Delaying your first coffee until now. You don’t need caffeine as soon as you open your eyes because high levels of the ‘stress’ hormone cortisol are waking you up. Later, you’ll feel the benefit from a boost of caffeine.

10am

IF YOU are going to feel sunny today, this is the most likely time. According to the Twitter studies, people are at their least angry at this point in the day.

Try: Booking a counselling session. If you have a problem or need advice, you make the biggest gains with a mid-morning appointment, according to research. The cortisol in your system helps control fears, while your fresh brain is primed to focus and learn.

11am

THIS is the high point for the brain’s analytical powers, so you’ll be at your most productive until midday. Positive emotions are still rising, but will peak very soon.

Try: A quick breathing exercise to control cortisol if you’re stressed. Take a deep breath, pause, then exhale slowly for a count of five and repeat four times.

12pm

NOON is when we’re most likely to react to positive emotions and sensations. It’s the high point in the working day for feeling happy.

Try: Making important phone calls or negotiating a pay rise. Research shows you’re more likely to be constructive now; afternoon calls tend to be more combative.

1pm

OUR good mood begins to wane, as the afternoon slump nears. But 1pm is a time of the day when we feel at our warmest towards others, before our mood falls sharply.

Try: Music with 125-140 beats per minute if you’re going on a lunchtime run. That’s Queen’s Killer Queen (125), U2’s Where The Streets Have No Name (126) or Coldplay’s Viva La Vida (138). Research shows it’s the optimum pace for activating the brain’s pleasure circuits.

2pm

THIS is the low point for happiness in the working day; you’ll also feel most tired because your body is entering a natural resting phase, having been up for seven hours.

Try: A cup of coffee before a 15 to 20-minute nap (or if you can’t sleep, go somewhere quiet and rest. The caffeine will take 25 minutes to work, so you’ll feel energised on waking).

3pm

ONE survey of office workers found we were at our most unproductive at 2.55pm. It’s not surprising: serotonin is low and our blood sugar