Could the amount you sleep be making you fat?

BODYTEC: What is the optimal amount of sleep a person needs and why?

LISA RALEIGH: Like many things, the right amount of sleep is all about balance. Studies have shown that those who sleep for less than six-and-a-half hours or more than eight-and-a-half hours usually have more body fat. The perfect balance lies between seven and eight, although there are exceptions – athletes, for example, often need more rest.

Sleep is such an integral part of our body's’ functioning and is so often underestimated! Some effects of lack of sleep include:

  • Impaired attention, alertness, concentration, reasoning, problem solving and memory.
  • Weight gain. Inadequate sleep increases cortisol levels and increases ghrelin – the peptide that stimulates hunger. It also reduces leptin, a hormone that signals fullness, leaving you storing fat and hungry.
  • Depression. Over time, a lack of sleep and sleep disorders can contribute to the symptoms of depression. Insomnia and depression are often linked, and unfortunately feed off each other, since sleep loss can aggravate the symptoms of depression, and depression can make it difficult to fall asleep. It has been proven that people who sleep less than five hours a night feel stressed, angry, sad and mentally exhausted. 
  • Premature aging. They don’t call it beauty sleep for nothing! During a deep sleep, growth hormones are released to repair tissue and patch up the wear and tear of the day. 

What are common things that affect sleep?

Training too late in the day (after 6pm) can raise your body temperature and rev your metabolism to the point where you can disrupt your sleeping patterns. Caffeine is an obvious one. It doesn’t only keep you awake, it also pushes your internal clock back so you want to sleep later. Each cell in your body has its own circadian clock and caffeine disrupts a core component of it.
The sugars in alcohol and carbohydrates also often keep us awake if we indulge too late, as the body is still fired up while metabolising them. Snacking before bedtime, particularly high sugar or carb snacks might prevent you getting a good sleep. Environment also plays a big role. By now we all know the effects of blue light from electronic devices simulates the daylight that promotes us staying awake. Time on your phone and laptop right before bed is a no-no.

What is the link between stress and insomnia?

Stress is one of the leading causes of insomnia, and also has a self-perpetuating effect, since lack of sleep adds more stress to the body and mind. Chronic stress will boost your heart rate and blood pressure and can permanently raise your levels of cortisol – which in turn compromises your sleep more.

Are there any things that one may not have considered that could be behind sleep disruptions?

Certain heart medications commonly cause sleep problems, as do herbal varieties that are designed to stimulate mental or physical activity. Sleeping tablets are also a bad idea, as the body builds up a tolerance over time, often promoting insomnia. Vitamin and mineral deficiencies can also play a role. Omega-3, for example, promotes a better quality sleep, as does magnesium.


Please explain why it’s not just the length of sleep, but depth of sleep that counts.

We have REM and non-REM sleep. We dream in both states, but REM is thought to be the more active stages of sleep, where we process problems and address our fears versus the deeper, less active dreams of non-REM sleep. We need both, but too much REM sleep shows less proper rest, as well as more depressive tendencies. An activity tracker can help you monitor your sleeping patterns and see how many hours of deep sleep you get each night, and at what time.
The length of your sleep also doesn’t always represent the quality of your sleep. Interrupted sleep (typically meaning four prolonged awakenings across eight hours in bed) has a more detrimental effect on the body than restricted sleep (i.e. if you only slept for four uninterrupted hours).

Do you believe in ‘insomnia’, or does someone who suffers from this simply need to change their lifestyle?

Insomnia is very real, but it most commonly is a result of a mismanaged lifestyle versus simply being ‘inherent’. Once you have become someone who suffers from chronic insomnia though, positive changes in your lifestyle take a longer time to improve your sleep quality than someone who has simply not been sleeping well lately.

Does exercise assist with quality of sleep in any way?

Absolutely. Just 30 minutes of exercise three times a week can boost your sleep over time. 150 minutes of moderate to vigorous activity a week, which is the national guideline, can offer those formerly not exercising a whopping 65 percent improvement in sleep quality. On the flip side, those who get a poor night’s sleep almost always exercise for a shorter period than usual the following day.

Please give us tips that people can implement straight away that will give them better quality sleep.

Unplug. Not only is the content on your laptop or phone stimulating, but electronics emit a blue hue that mimics daylight. Try turn off all gadgets an hour before bedtime.

Watch the caffeine: whether it’s caffeine, cola, dark chocolate or cappuccinos, it may be time to cut back. Caffeine tolerance is unique to the individual, so try gauge your limits. Either way, play it safe and make your last dose around noon. A brisk walk is just as energising as caffeine.

Don’t overhydrate. Downing too much liquid at night guarantees midnight bathroom runs. Even though your body helps by naturally reducing urine production during sleep, aim to cut off liquids at least an hour before bed.

Build a comfy nest. Considering how many hours you spend in your bed, it may be time for an upgrade. Most mattresses last from five to ten years, and if yours is sagging it won’t provide the support you need.

Keep your room tidy. People who make their beds before sleep report better rest. This may be because stress levels are lower in a tidy and organised environment.

Adjust your aircon. If you have an aircon, set it to around 18 degrees. This is the temperature at which researchers have found your body can stay comfortable without having to do anything like shiver or perspire.

Stock up on scents. Lavender is always associated with better sleep, so spritz your pillow with a linen spray or pop a few drops under your pillow.

Are their certain foods you should avoid if you struggle to sleep?

Greasy, fatty foods not only make you feel sluggish the next morning, they can disrupt your sleep as well. Your stomach works overtime to digest all that food, causing discomfort if you eat them soon before sleep. Keep the fast food and ice cream away from bedtime. Sugary, high carb foods are also worth skipping – these require fast digestion, spiking your sugar levels before bed.

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