The impact of sleep deprivation on your body

A growing body of research suggests that there’s a link between how much people sleep and how much they weigh. If you’re not sleeping enough, the effects could be more significant than just dark circles under your eyes. Here we look at the surprising fact of how your size and your sleep are closely linked.

The rise of obesity over the last few decades is paralleled by significant reductions in the length of time we spend asleep.

At the same time, a large number of studies have reported associations between impaired sleep and the likelihood of developing obesity or diseases such as type 2 diabetes. (Note: the act of sleeping less does not in itself make you fat – after a few disturbed nights your body won’t automatically have created fat!).

We’re not talking about a cause/effect link here. We’re talking correlation. As the number of people getting less sleep has risen, so the number of people at risk of life-threatening metabolic and cardiovascular diseases has risen too. The reason for this correlation may lie in the effects that poor or less sleep may have on your behaviour and physiology. It’s these effects that can contribute to weight gain.

Inactivity – if you’re feeling lethargic and tired, you’re less likely to exercise and more likely to take shortcuts like using the lift rather than the stairs. This decreases the amount of calories you’re burning, which has a direct effect on your weight.

Mood fluctuations sleep is vital to regulating your mood. Less sleep could see you happy one moment and feeling low the next. Low mood can trigger emotional or ‘comfort’ eating, when our bodies crave high fat, high sugar foods. When eaten, these foods trigger the pleasure response in your brain, and we’re hardwired to crave them in times of distress.

Reduced leptin levels – less of the hormone that tells you you’re full could see you overeating without realising it.

Increased grehlin levels – more of the hormone that tells you you’re hungry will have you seeking out more food and snacks, even if you’ve consumed the right amount of food for you that day.

Recent analysis conducted by King’s College London reviewed dozens of small studies involving sleep and appetite. It showed that, although not everyone is affected in the same way, on average getting less than seven hours of sleep a night led to people eating significantly more overall.

A bad night’s sleep disrupts the two key hunger hormones, ghrelin and leptin and this combination leaves us feeling physically hungrier, causing us to eat more. Studies also suggest that when we’re exposed to food while sleep deprived, there is increased activation in areas of the brain associated with reward. This can lead to us choosing foods that are higher in sugar and fat, rather than selecting healthy options.

All of this can help to explain why, in the long term, there’s a strong connection between poor sleep, weight gain and health problems like type 2 diabetes. The simple solution is to make sure you’re getting enough sleep. For adults, 7-8 hours of sleep per night is associated with the lowest risk of incidence of cardiovascular diseases.

Find out more:

Will going vegan make you healthier?

The popularity of veganism has really taken off. More than four times as many people are now opting to cut animal products out of their diet than they were four years ago. Across Britain, people are spending more money on vegan products, and plant-based diets are trending online. With major supermarkets catching on and stocking up on vegan-friendly food – and even restaurants starting to offer vegan dishes and menus for their customers, we were wondering how easy is it to go vegan and stay healthy?

A recent episode of the BBC TV programme “Trust Me I’m a Doctor” posed this very same question, and set Cambridge Neuroscience Research Associate Dr Giles Yeo the task of going vegan for one month.

Specific aspects of Giles’s health were assessed by Dr Mellor, a dietitian and senior lecturer in human nutrition at Coventry University before and after his month of being vegan. We measured his cholesterol, body fat, weight, and his levels of iron, folate, zinc and vitamins A, E, D and B12. Dr Mellor also gave Giles a list of foods to eat to stay healthy and avoid becoming deficient in key nutrients.

The results

After one month on a vegan diet, Dr Yeo lost 4 kg and his body fat dropped by 2%. His BMI improved by 6% and his cholesterol fell by 12%. Thanks to Dr Mellor’s food suggestions, he didn’t become deficient in any key nutrients. However it’s more difficult to be so nutritionally diligent in the longer term and vegans can become deficient in nutrients you’d normally get from animal-based foods, such as iron and vitamin B12.

Essential nutrients for vegans

There are certain essential nutrients that we normally get from animal-based foods that vegans need to replace with alternative foods or supplements.

  • Vitamin D – Vitamin D is important for our bone health. It is produced in our body when sunlight hits our skin and is also present in a few animal products. Vegans might want to consider taking a supplement, but beware that not all of them are vegan-friendly. Vitamin D2 is always suitable for vegans, whereas some sources of vitamin D3 derive from sheep’s wool.
  • Vitamin B12 – We need vitamin B12 to keep our blood healthy. It is not produced by plants, but there are plenty of vegan products on the market, such as milks, spreads and yeast products, which are fortified with it.
  • Omega 3 Fatty Acids – These are essential for brain function and are found in oily fish. Other good sources are flaxseeds, chia seeds, walnuts and soy beans.
  • Calcium – While calcium is synonymous with dairy, there are plenty of vegan sources too. Tofu commonly contains calcium and there are calcium-fortified alternatives to cow’s milk available. Other good sources include green vegetables such as kale, pak choi, okra and spring greens, as well as almonds, chia seeds and dried figs.
  • Iodine – Iodine deficiency is not uncommon in the UK, even in non-vegans, particularly amongst young women. In the UK, cow’s milk is our main source of iodine, and the non-dairy alternatives, like almond drinks, have much lower levels. You can get iodine from seaweed (though the amounts are unpredictable) but you may need to take a supplement.
  • Protein – Some vegans worry that they aren’t getting enough protein, a nutrient people tend to associate with meat. However, eating a balanced diet with plenty of plant-based protein sources should provide all that you need. Particular foods to try and include are tofu, soy, beans and pulses.
  • Iron – Cutting out meat can also affect your iron levels – red meat contains a form of iron that is easy for our body to absorb, whereas the iron that you get in fruit and veg is less readily available. One solution is to accompany iron-rich vegan foods with a rich source of vitamin C, like orange juice, which helps to make the iron more absorbable.

And what does my favourite chef say about veganism?

Many argue that we should all be making a conscious effort to reduce consumption of animals and animal products for the sake of our health and for the planet. Vegan or not, a diet high in fruit and veg and plant-based food is a good starting point for a healthy lifestyle.

You can find out more about this experiment on the Trust Me I’m a Doctor website here >>

EGGS: Nature’s most nutrient-dense food

“But eggs contain cholesterol!” I hear you cry, “And doesn’t high cholesterol cause heart disease?” Well, although eggs do contain cholesterol, the amount of saturated fat we eat has more effect on the amount of cholesterol in our blood than the cholesterol we get from eating eggs.

Eggs are one of nature’s most nutrient-dense foods and contain an ideal mixture of nutrients. Along with high quality protein, eggs are also naturally rich in vitamin D, B2 (riboflavin), vitamin B12, iodine, selenium and other essential dietary vitamins and minerals.

SO WHAT HAS CHANGED?
Previous limits on egg consumption have been lifted as it is now known that the cholesterol they contain does not have a significant effect on blood cholesterol.

A high level of blood cholesterol increases the risk of heart disease. It was originally thought that eating cholesterol-rich foods was an important cause of high blood cholesterol levels and therefore increased heart disease risk.  In the past it was thought that people should limit the number of eggs they eat because they contain cholesterol. However, only around a third of the cholesterol in the body comes from the diet – our bodies make the rest. It is now accepted that the amount of saturated fat that we eat has a much greater effect on our blood cholesterol levels than cholesterol in the diet.

Recommendations on limiting egg consumption have now been relaxed by all major UK heart and health advisory groups, including the British Heart Foundation and the Department of Health.

This means that most people can eat eggs without adversely affecting their blood cholesterol levels, provided that they are eaten as part of a healthy diet that is relatively low in saturated fat.

The healthiest ways to cook eggs

Boil or poach eggs (preferably without adding salt) rather than frying and avoid adding butter to scrambled eggs. Frying eggs can increase their fat content by as much as 50%.

Find out how easy it is to cook the perfect poached eggs with Jamie Oliver:

Eggs and fitness

Whenever we do any form of exercise we gain muscle – how much depends on the intensity and frequency of exercise. The more muscle mass your body has, the more calories you burn, even when resting. To build muscle mass efficiently the correct nutrients must be consumed – this is where the introduction of nutrient-dense foods such as eggs to your diet can have huge benefits.

One of the main substances our muscles need to repair and grow is protein. High in protein, eggs are an ideal choice for post-workout nutrition. Plus, in addition to their high protein levels, eggs contain all eight essential amino acids that are required for prime muscle recovery.

You can find out more information about the many benefits of eggs from the British Egg Information Service (see below).

Thanks to: