How does your blood sugar stay level when you sleep?

[visceral]

How come it doesn't go really low when you're asleep? I mean, you can sleep for 12 hours and so and feel fine when you wake up....if you went for 12 hours without eating when awake you'd probably pass out from hypoglycemia. How does your body keep it level?

[iNow]

During periods of inactivity, your body produces less insulin. It is the insulin which breaks down the sugars and leads to hypoglycemia. You have a fairly constant rate of insulin released from the pancreas throughout different parts of the day. This is known as your "basal rate." That basal rate tends to be lower when you are asleep, therefore less insulin in put into your system, and blood glucose levels remain relatively steady. There are also sugars in your liver which get broken down when glucose levels decrease during the night, so that is an additional method the body uses to help maintain those steady levels.

[visceral]

Ah, thanks for reply.

[mrburns2012]

To be more accurate, glucose breakdown often refers to its conversion to some form of energy like ATP. After a meal, your blood glucose level will skyrocket, so to protect you from hyperglycemia, your body releases insulin which signals organs like muscles, fat tissues and liver to remove glucose from blood and store it. The stored glucose can be released back into blood when needed (e.g. when you're asleep) to protect you from hypoglycemia. The hormone telling the body to release stored glucose into the blood is glucagon.

 

See this graph, if you're a visual person. http://en.wikipedia.org/wiki/File:Suckale08_fig3_glucose_insulin_day.jpg

Edited February 23, 2009 by mrburns2012

[npts2020]

How come it doesn't go really low when you're asleep? I mean, you can sleep for 12 hours and so and feel fine when you wake up....if you went for 12 hours without eating when awake you'd probably pass out from hypoglycemia. How does your body keep it level?

 

Anyone with normal body chemistry can survive many days without food and not pass out. Try googling hunger strike/Bobby Sands or fasting/Dick Gregory. I know both those individuals have gone without food for over a month (Sands died after 66 days but was not in the best of health to begin with).

[Mr Skeptic]

How come it doesn't go really low when you're asleep? I mean, you can sleep for 12 hours and so and feel fine when you wake up....if you went for 12 hours without eating when awake you'd probably pass out from hypoglycemia. How does your body keep it level?

 

The body stores energy in the form of glycogen for fairly quick release, and fat for long-term storage. There are controls to ensure that when we eat, the glucose is stored away so that we don't have too much in circulation, and when we fast, some is brought out of storage.

 

As I understand it, people can go for about a month without eating. Personally, I went for a week without eating, and did not feel like passing out. In fact, I got less hungry after the third day without food. Likewise, when you sleep your mind is not reminding you that it is dinner time or breakfast time. Most of hunger is in the mind.

[visceral]

I guess I'm weird, I get really weak if I go too long without eating. I can actually fall asleep from low blood sugar, though admittedly I eventually start producing adrenaline to compensate.