We all know that a bad night's sleep can leave us feeling grumpy and lethargic. But aside from these obvious issues, lack of sleep can affect our overall health and wreak havoc on our waistlines.
It can be easy to deprioritise sleep in our modern-day hectic schedules, but to do so could be hugely detrimental. Here we'll discuss exactly how sleep, health and weight are linked, as well as ways to start prioritising your shut-eye where needed.
If we miss the odd night's sleep or have an occasional bad night, it's not a huge concern. But, if we continuously get inadequate sleep, the long-term effects on health can be pretty alarming. Issues can include the following:
It may surprise you to hear that not getting enough sleep can also impact our waistlines. The link between sleep and body weight is complex, but evidence supports a relationship – so let's look into how the two are linked.
The big question is...does lack of sleep really affect our waistlines? The answer is yes! But it's not necessarily the lack of sleep that directly leads to an increase in fat stores in the body, it's more about how it alters our behaviours and choices throughout the day.
It's possible that inadequate sleep influences what we choose to eat the following day, plus how much we eat. In one study, researchers observed the brain activity of healthy volunteers using MRI scanners. They took images of the brain on two occasions – following one good night's sleep (8 hours plus) and one night of total sleep deprivation. During the scan, the volunteers were shown pictures of food, and their brain reaction to the pictures recorded.
The researchers made a very interesting discovery. After a night of no sleep, the volunteers showed a high level of activation in the area of the brain involved in the desire to eat, compared to the volunteers who had a good night's sleep. After just one night of sleep deprivation, there was a marked difference in the brain's response to food and appetite, suggesting that continuous poor sleep patterns could influence both the way and the amount that we eat. Over a longer period, this alteration in the brain's handling of appetite signals could mean a huge change in calorie intake resulting in weight gain and the inability to lose weight effectively.
Lack of sleep has many different effects on the body, not least that it reduces our ability to function properly. It can result in less energy which unsurprisingly affects our activity levels. Research has found that when people have had a bad night's sleep, their energy expenditure the following day is reduced.
Making the decision to hit the gym is tough enough without the added hurdle of tiredness and fatigue getting in the way! So it makes sense that inadequate sleep may lead to less activity.
Early starts, late finishes, or working right through the night – shift work can take a big toll on your body in many different ways. Whether you're a policeman, doctor, nurse or working nights on a production line, the effect of shift work doesn't discriminate. In the short term, it can cause sleep disturbances, fatigue, stress and irritability.
There is also evidence showing that shift workers, particularly those working nights, have a greater tendency to gain weight. Although we don't know precisely why this is, it's likely a combination of eating late in the day, snacking more, having a sedentary lifestyle with more naps, and feeling less inclined to do exercise when off shift.
It's also possible that hormones play a role, as the natural sleep-wake cycle is disrupted. There is some research to suggest that the hormone leptin is lower in people who regularly work shifts. This hormone is responsible for making us feel full, so lower levels can lead to overeating and weight gain.
Here are some practical tips to help if you are a shift worker:
On the flip side, our weight and dietary choices can also have an effect on sleep quality – so the relationship works in both directions. Here are some of the ways our weight and diet can impact our quality of sleep.
Being overweight can actually affect sleep. Obstructive sleep apnoea is a condition in which breathing is temporarily disrupted for 10 or more seconds at a time.
The reason being overweight increases the risk of developing sleep apnoea is because soft tissue can build up around the throat. When asleep and more relaxed, the soft tissue around the throat can start to obstruct the airway, temporarily stopping breathing.
If you suffer with sleep apnoea and are overweight, it's highly recommended that you lose weight as this can ease the symptoms or even cure the condition in many cases.
What we eat potentially affects our sleep too. For example, having a particularly fatty or spicy meal later on in the day can cause gastrointestinal issues which subsequently disrupts sleep quality. Equally, going to bed hungry can cause us to wake in the night, again affecting the quality of our sleep.
The Sleep Foundation also state there is a relationship between diet and sleep quality, with some studies highlighting a lack of certain vitamins in the diet is associated with sleep issues. As with most things, a well-balanced diet rich in nutritious foods is the best approach for ensuring sleep quality.
It's clear that getting enough good-quality sleep is essential – so how can you make sure you do this? To help here are our tips for getting a good night's sleep.
Nutritionist Emma White (ANutr), MSc Human Nutrition is passionate about how food science applies to the human body, and how the nutrients in what we eat affect us and ultimately have an impact on our health.