Finding it difficult to get a good night’s rest can be due to fluctuating blood glucose levels that go too low or too high during the night. Conversely, a poor sleeping pattern can adversely affect your blood sugar levels.
Night-time hypoglycaemia refers to blood glucose dropping to dangerously low levels during the night. Your blood glucose levels can also reach dangerously high levels when you are asleep.
If your blood sugar levels go too high or too low during the night, you will probably find that you feel tired the whole of the following day. Indeed lethargy and insomnia can both have their roots in poor blood sugar control. Getting on top of your blood glucose levels can be the key to a healthful sleep.
Low blood glucose at night
Night-time hypoglycaemia affects nearly everyone with type 1 diabetes. It also affects a significant minority of type 2 diabetics.
Here’s what happens.
Glucagon is a hormone that raises blood glucose levels. It is released by the pancreas when blood sugar levels fall too low. It works by causing the liver to convert stored glycogen into glucose, which is released into the bloodstream.
The problem is that glucagon production is lower when you are asleep. This means that, as your glucose levels fall during the night, not enough glucagon is released to bring your blood glucose level back up Glucofort again. At the same time your blood glucose is continuously falling as the time since your last meal or snack is getting longer and longer.
It can be difficult to know when you have night-time hypoglycaemia as the symptoms may not be apparent during sleep. Waking up in the morning feeling tired, irritable or confused, or feeling damp from perspiration suggests that you may have experienced this hypo.
Other symptoms include crying out during the night or having nightmares. Your sleeping partner will be able to tell you if you have been making noises during the night.
You may also experience blood glucose levels in the morning that are higher than usual, which is due to your blood sugar levels rebounding from their low level when you wake up. This is known as the Somogyi effect.
The problem with night-time hypoglycaemia is that if you don’t wake up when you are having an episode, your low blood sugar will remain untreated and become more pronounced, which can be dangerous.
If you suspect that you are having bouts of night-time hypoglycaemia, you should test your blood before you go to bed and when you wake up. Alternatively you could wear a continuous blood glucose monitor which can sound an alert if your blood sugar goes too high or too low.
To prevent night-time hypoglycaemia, try to maintain a consistent routine of diet and activities in the evening. A snack before bed can also help.
High blood glucose at night
The link between high blood glucose levels and poor quality sleep has been well established by researchers.
If, when you try to fall asleep, your blood sugar level is high, you will sleep poorly. There are two possible reasons for this.
It could be that the high level makes you feel too warm to get a good night’s sleep or too irritable and unsettled. Another reason is that you will need to get up and go to the toilet many times during the night.