Did you get less than five and a half hours sleep last night?

There have been many times where I have, through meeting work deadlines, having a good night out with friends or through the “joys” of parenthood, and I have not given it a second thought.

That is until I discovered what it is doing to my health.

We all know how terrible we feel when we have a bad nights sleep but what most of us don’t realise it that it has a profound effect on our hormones. Researchers from Stanford University discovered that people who sleep less than five hours a night had 15% more circulating ghrelin and 15% less leptin than those who slept eight hours or more. Ghrelin is a hormone that when elevated makes us feel hungry while leptin makes us feel full.

So poor sleep essentially sets us up to feel hungry, crave food and have less satisfaction after eating. It’s not a wonder that people who sleep less have a higher BMI.

What I also find interesting is that just one night of 4 hours sleep can make you insulin resistant for the following day. A group of researchers discovered this when they forced healthy men and women to only sleep for 4 hours and compared this to a usual nights sleep.

The reduction in insulin sensitivity dropped by 25%, to put this in perspective this amount of resistance to insulin is comparable to having 10kg more body fat!

Further to this, if you limit yourself to this amount of sleep for six nights in a row your insulin sensitivity drops a whopping 40%, and here you’re well on the way to developing type II diabetes. It is not a wonder that diabetes and sleep apnoea are intrinsically linked.

If you are already a type II diabetic, improving your sleep may be a great way to better regulate you blood sugar levels. In a study that has just been published in Diabetes Care it was revealed that insomnia increases your blood sugar levels considerably. The level of impact is highlighted if we compare two diabetics who were identical in every other way other than one of them suffering from insomnia. If the well slept diabetic had a fasting blood sugar of 7.8 mmol/L the one with insomnia would have a blood sugar level of 9.4 mmol/L!

So if you are struggling with your sleep, here are a few suggestions:

1. Use relaxation exercises just before going to sleep. This helps switch your mind off from past and future events and enables a better night’s sleep.

2. Do not eat within 2-3 hours of sleep.

3. Use a temperature-controlled mattress and some french flax sheets.

4. Eat low carbohydrate meals, particularly at night.

5. Avoid caffeine and stimulants after midday.

6. Keep your bedroom as dark as possible.

7. Keep moving on a daily basis, it is your body’s way of naturally regulating it’s hormones and neurotransmitters.


As part of diabetes week we will be holding a seminar on this as well as many other things you can do to better regulate your blood sugar levels. If you would like to hear more about this topic, and live near Adelaide, South Australia, please visit our diabetes events page for details of this seminar.