Unit 1: Mindset

Are you getting enough sleep?

Madeleine Hawkes, Weight Loss Expert

PGCert Obesity & Weight Management

BSc (Hons) Nutrition and Dietetics,

BSc (Hons) Psychology

Sleep and its regenerative powers have slowly been making their way into our collective consciousness. Sleep apps, trackers and soft alarms are becoming the next wellness obsession. So how important is sleep, how does it affect your weight, and how can we get enough of it?

Why is sleep important to weight loss?

A number of studies have shown a link between a lack of sleep and weight gain. When we don’t sleep well we tend to feel hungrier because our bodies produce higher levels of ghrelin (a hunger hormone) and lower levels of leptin (a satiety hormone which reduces appetite). Sleep deprivation also interferes with our insulin response which means it takes longer to feel full when eating, and therefore we eat more. 

What’s the science behind sleep?

Hormonal fluctuations, driven by our circadian rhythm and sleep pressure, make us fall asleep each day. 

Our circadian rhythm – the body’s natural sleep-wake cycle – is influenced by light and darkness. Darkness at night sends a signal to your brain, triggering an increase in melatonin production to encourage us to sleep. 

Sleep pressure – our natural urge to sleep – builds throughout the day from the moment we wake up. It decreases when we sleep, reaching a low point after a full night of sleep.

Sleep is vitally important because it helps us manage our emotions, cope with stress, repair physical injuries, reboot our immune system, and reset our hormones so that we can function effectively every day.

So what causes us to sleep poorly?

There are many lifestyle factors that can consistently disrupt our sleep quality, including: 

  • Caffeine
  • Jet lag
  • Stress
  • Reduced activity or exercise levels
  • Unstable blood glucose levels
  • Alcohol
  • Underexposure to natural light
  • Overstimulation (from phones, TVs, noise, conversation) before bedtime

We all have different sleep requirements

What constitutes a good night’s sleep varies hugely from person to person. We all need different amounts of sleep, and have our own sleep-wake cycles and sleep schedules that work best for our bodies. 

Your chronotype describes the sleep-wake cycle your body naturally prefers. It’s influenced by three main things: genes, age and development, and light exposure. People with an ‘early chronotype’ are morning larks – they feel much more productive when they get up early, and go to bed early. ‘Late chronotypes’ are night owls – they naturally wake up later, go to sleep later, and are often most productive later in the day. Knowing what your chronotype is can really help you to optimise both your sleep schedule and your daytime performance.   

Take action ⚡ 

Ask yourself whether you feel you’re getting enough sleep for you. These questions might help you decide:  

Do you feel you’re able to function optimally throughout the day?

Do you need an alarm clock to wake you every morning? 

Do you oversleep extensively on weekends or holidays without your day-to-day routine?

Are you often irritable?

Do you need a nap during the day?

Do you rely on caffeinated drinks to give you enough energy throughout the day?

If you answered “Yes” to most of these questions, you’re probably not getting enough sleep.

Over the next couple of articles we’ll show you how to supercharge your sleep by making changes to your day-to-day and bedtime routines. 


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While we've ensured that everything you read on the Health Centre is medically reviewed and approved, information presented here is not intended to be a substitute for professional medical advice, diagnosis, or treatment. It should never be relied upon for specific medical advice. If you have any questions or concerns, please talk to your doctor.