From your appetite to your willpower, it seems sleep holds some sway. We shed light on surprising ways your slumber may influence your efforts to keep the weight off. Words: Ceri Moorhouse
When it’s been a bad night between the sheets, and your alarm clock is sounding, it’s so tempting to hit snooze. Then if you end up running late, you might grab some breakfast on the go, perhaps a croissant, or even skip it altogether. And if you don’t feel up for a run later, you might put it off ‘until tomorrow’. It’s easy to see a tired morning playing out this way.
You probably know by now that sleep is essential for good health, not just re-energising your batteries for the day ahead. Regular poor sleep has been linked to heart disease and diabetes. But have you ever considered whether the standard of your slumber may be affecting your weight? We asked the experts about some ways it may figure in the equation.
The hunger hormone
Hormones called ghrelin and leptin tell you, respectively, when you’re hungry and when you’ve had enough to eat. It seems there may be a link between these and your shuteye.
‘Ghrelin is the “hunger hormone”, which boosts your appetite, particularly for sugary foods. Fatigue can make you eat more in an attempt to stoke your energy levels, and studies have found that chronic sleep deprivation can increase your levels of ghrelin,’ says Sarah White, Clinical Director at Bupa UK. ‘Leptin is the hormone that tells you when you’ve had enough to eat. Not sleeping enough can decrease your levels of leptin.’
This may impact on your eating habits. ‘If your body is producing increased levels of ghrelin your appetite will be bigger and your cravings will increase, particularly for sugary foods. Similarly, if your levels of leptin have decreased, your body is less likely to tell you when it’s had enough to eat, meaning you are likely to overeat. Naturally, this would lead to weight gain if not managed appropriately.’
Smart food choices can help here. ‘There is a growing body of evidence that eating breakfast can help with weight loss/maintenance by waking up our metabolism which slows down overnight, and by preventing overeating due to excessive hunger later in the day if we skip breakfast,’ says Nicole Rothband, Specialist Dietitian and BDA Spokesperson.
‘It is sensible to eat a combination of foods containing protein and wholegrain carbohydrates with accompanying fruits and or vegetables along the lines of the Eatwell Guide at breakfast time.’ You can download a PDF of the Eatwell Guide at nhs.uk.
What you eat in the evening may be significant. ‘If we eat energy-dense foods, that is foods that are high in fats and sugars, close to bedtime there is a higher chance of us ending the day in positive energy balance unless we are very active before we go to bed. This will then lead to weight gain,’ says Nicole.
Many of us look to an edible pick-me-up when we feel low on energy. ‘When the body is tired you’re more likely to crave unhealthy options which are high in both sugar and calories,” says Sarah. “If you’ve not had enough sleep, energy levels are low and you’ll feel like you need a quick fix. This will likely mean craving more coffee and energy drinks in the mornings, or a chocolate bar and other sugary snacks to give yourself a ‘pick up’ later in the day.’
Try healthier snacks, suggested by Nicole: a banana, grapes, nuts and raisins, or nut butter with apple slices or carrot sticks.
Relying on coffee to keep you going on tired days may lead to further poor sleep as well as other health issues. ‘People don’t realise how much caffeine can affect your sleep,’ Sarah says. ‘Caffeine is a stimulant and acts on the central nervous system, increasing heart rate, which in turn can make you feel more energised and alert. As well as impacting sleep, it can cause dehydration, headaches, anxiety, and light-headedness.’
She recommends that adults shouldn’t consume more than 400mgs of caffeine throughout a day – the equivalent of about four coffees. ‘Many soft drinks and energy drinks contain around 80mgs of caffeine, too, so it’s worth taking this into account. It’s best not to have any caffeine in the six hours before you go to bed so it doesn’t affect your sleep.’
Note that your caffeine hit may bring other considerations, too: ‘Some caffeinated drinks and snacks contain a lot of sugar, which poses its own risks to staying healthy when taken in excess,’ adds Sarah.
As alternatives to caffeinated drinks, Nicole recommends fruit or herbal teas, redbush (Rooibos) with or without milk or mint leaves and or lemon slices in hot water.
Make your move
When you wake up unmotivated by the thought of an energetic workout, it may help to remember some of the benefits. ‘The intensity of a workout determines your overall calorie burn. If you want to make weight loss safe and sustainable, I’d recommend a mix of high-intensity and moderate workouts,’ says Israel Rivera, Head of Group Exercise at Virgin Active.
‘Personally, I prefer high-intensity workouts in the morning as they have a long-lasting effect on revving the metabolism. I find that mixing up my exercise routine with more intense sessions gives me an endorphin rush that lasts all day.’
However, Israel says, ‘There is no one size fits all approach to exercise – the best advice is the listen to your body and do what feels right for you no matter what time of day.’
It’s worth bearing in mind that health issues can contribute to poor sleep, and if you suspect an underlying cause, you should see your doctor. ‘These can include anxiety and depression, arthritis, asthma, chronic pain, and neurological conditions such as Parkinson’s,’ says Sarah. ‘If you want to find out more about how to improve your sleep, a health assessment can give an overview of your lifestyle as a whole, with a medical professional able to build an individual plan that’s right for you and the way your body works.’