hormones

Sleep, stress and body weight

Recognising the value in sleep

Don't you just love a good night's sleep? Lying down after a long day, supported by the soft sheets and springs. Relax.

Sleep is a restorative process for the brain. But how often do we find our minds spinning, unable to switch off before bedtime? Sleep duration has steadily decreased over the past century. From an average of 9hrs in 1910 to 7hrs in 1995. Hundred's of epidemiological studies have shown a strong relationship between sleep disturbance and obesity. The mechanisms are complex and but the solutions are simpler than you may think.

Stress and sleep: A vicious circle

The brain was once described to me as a muscle. If you don't use it, it gets weak and slow.  If we use our brain all day and stress all night, failing to rest it, the result is a brain that is constantly operating in a sub-optimal way. Making below-par decisions because it is constantly fatigued. The purpose of sleep is not to rest your body, but your brain. Most of us do nowhere near enough physical activity to warrant resting for 9 hours every day. But almost anyone who has a job, cares for someone or is in education, will most certainly need this rest so their BRAIN can restore itself and process the day's events. A stressful day frequently leads to a poor night's sleep (tell me something new), but what has this got to do with weight gain...?

The link between poor sleep and gradual weight gain

The body is a beautifully complex system. It is regulated tightly by a number of pathways and mechanisms that impact our mood, our weight and even our appearance. Most notable is how our hormones can adjust and react to our environment, literally changing our behaviour. Under normal circumstances, our hormones are released at certain points in the day. If this 'normal' cycle is disrupted, hormone release can become compromised and fall out of rhythm with the body's normal pattern. Take a poor nights sleep (low quality and less than 6 hours). When you wake up, you will have more Ghrelin, the hormone that makes you feel hungry and less Leptin, the hormone that makes you feel full. Under normal conditions, the body should have low Ghrelin levels in the morning and slightly raised Leptin. What this means in real terms is when you wake after a poor night's sleep, you may feel an urge to eat more than you actually need. One study showed that after sleep-deprivation, healthy young adults increased caloric intake the next day by 14% with a preference for carbohydrate-rich food.

And the idea that this 'blip' in normal routine can be remedied with an intense bout of exercise is nonsense. Ignoring the fact that very few people will even entertain the idea of a game of squash after 6 hours sleep and 10-hour shift, the best thing one could do would be to get a good nights sleep and resume a normal routine the following day.

Sciencey bit, simplified

So, you made it through a stressful day. After a measly 6 hours sleep, your foggy brain gets you through another working day and ready for bed, guilty for not going to squash. Again. The environment inside your body is now all over the place. Cortisol, the stress hormone, is on the up. Cortisol stimulates insulin (storage hormone) release which in turn increases blood sugar levels. High blood-sugar levels during sleep mean your body is running on glucose (sugar) and not fat.

Completing the circle: How poor sleep can lead to weight gain

A poor night's sleep can lead to feeling stressed and creates an environment inside our bodies that denies fat-burning, due to elevated stress hormone (cortisol). Instead of burning fat, your body uses its most readily available store of sugar (either by making it or by you providing it via a meal). When you feel tired and stress, you are less likely to spend time preparing a meal that is nutritious. Instead, you'll reach for the most readily available meal that is likely processed and unlikely to satisfy you. We know refined, high carbohydrate foods are the source of gradual weight-gain and these are the exact foods you're likely to seek out when tired and stressed. These foods will cause big fluctuations in your blood sugar levels (sleep/awake/buzzing/sleepy etc.) throughout the day resulting in reduced productivity, capacity to make clear decisions and a general feeling of malaise. Unless steps are taken to break the cycle (see below) then the cycle continues, day after day, week after week.

Weight gain doesn't happen overnight. It is a long process that is a product of small, seemingly insignificant behaviours that contribute to a gradual shift towards insulin resistance, inability to access fat as a fuel and uncontrolled hunger. Don't be fooled into thinking 'willpower' will be enough to make you lose weight. It won't. Millions have tried and failed. Tackle the root cause, regain control of your sleep, learn to control stress and recognise that hunger doesn't always mean 'eat'.

Solutions to reduce stress

I am not an expert on how to reduce stress. But I am someone who doesn't get stressed very easily and I understand how to perform well under pressure. Try and identify areas in your life where the stress is originating; your job, financial situation, family. Speak with loved ones. Be open and honest with your feelings. Make a plan to change something by the end of the month. Socialise more. Take walks as often as you can. Explore positive ways to 'vent' (negatives would be excessive alcohol, smoking. Positives would be a walk, visiting relatives, calling an old friend). Try thinking differently about your situation, consider the good bits.

Change how you talk about your day

I stumbled across an enlightening TED talk 3-days ago. Alison Ledgerwood flawlessly presents a new way of thinking about your day. Deceptively simple but wonderfully powerful, this will be 10-minutes well spent:

How to make your bedroom somewhere you want to sleep:

  • Keep it tidy (thanks, Mum).
  • Keep it cool (17-19 Celsius is optimal). 
  • Consider changing your duvet during summer months to a lower tog.
  • Use an eye mask, ear plugs and blackout blinds if you work night shifts.
  • Have a good book or magazine on the go.
  • Use an alarm clock to save having your mobile in the room.
  • Start to wind down 2 hours before bed. Reduce screen usage, finish eating and drinking and prepare for the next day.
  • If you share a bed with someone, go to bed together.