If I eat right before bed, does my digestive tract keep on working throughout the night? Or does it shut down and pick up where it left off when I wake up?
asked byDavid_Csonka (6092)
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on February 25, 2010
at 03:37 PM
Your digestive system works just fine while you sleep. Digestion is parasympathetic nervous system dominant process and hence is most stimulated when you are most relaxed. WikiAnswers already has a answer for a very similar question so I will blatantly paste it here:
You will digest more efficiently during sleep as your parasympathetic nervous system is dominant at rest which favours blood flow through your enteric bloodstream which enhances absorption of gut breakdown products. Parasympathetic activation also stimulates salivary gland secretion, gastric activity and peristalsis.
During exercise, the sympathetic nervous system is predominantly active and the release of catecholamines stimulate peripheral vasoconstriction to the renal and mesenteric circulation effectively reducing blood flow to those systems whilst enhancing blood flow through the coronary and skeletal muscles system in the fight and flight response.
Relevant Wikipedia entries:
Caveat: GERD - If you have Gastroesophageal Reflux Disease it has probably been recommended to you not to eat before lying down. This is because it is believed that people with GERD have a lower esophageal sphincter that does not stay closed properly allowing stomach contents (especially acid) to reflux into the esophagus. Gravity helps keep the contents down when upright but you lose this advantage when reclined. Lying on your left side or prone can also force gastric contents up past a weak LES in a bellows-like effect if you have just eaten. Personally, I no longer suffer from GERD since eliminating sugar and most starches from my diet and now frequently eat a FAGE Classic full-fat greek yogurt before going to bed without reflux. I find it actually helps me get to sleep. (Note that I follow a PaNu style lacto-paleo diet which permits full-fat dairy.)
on July 13, 2010
at 05:28 AM
I remember reading that the bedtime food being bad theory has since been proven wrong. The new story is that calories are calories no matter when you eat em. I am not saying that I agree with that either, but that is the latest from some of the 'experts' who have said that no research supports eating at night to be particularly worse than eating at other times (mileage even varies considerably for diabetics from what I have heard). Without serious research it is hard for sure to know about anything is seems! Perhaps that is what is so convenient about paleo. For things we don't yet know or are unsure, a shortcut is to imagine what might be most natural. Of course, this is not a surefire approach, but it's hopefully better than nothing. I think Grok would have eaten often at night, especially whenever hungry. I personally find it hard to sleep when hungry because I keep waking up hungry, which is irritating. The hunger makes it harder for me to fall back asleep. So I try to make sure I eat enough at night to stave off hunger pangs until morning.
on October 13, 2011
at 07:35 PM
Of course,it does.But i wouldn't recommend eating and jumping straight to bed after greasy dinner.I am prone to GERD and eat very light for dinner,otherwise i sweat a lot,get headaches and acid taste in mouth.
on October 13, 2011
at 07:11 PM
If you look at a cat, dog or any domestic animal, they seem to sleep pretty soon after eating. Cows sheep etc, seem to eat all day until it gets dark - then they sleep. So do birds.
Why should we be different? I certainly feel sleepy soon after eating my evening meal - and I just suppose that I am designed to.
And on the rare occasions when I eat really early in the evening and go to bed late - I wake up RAVENOUS at about 2.00 a.m. Which RUINS my sleep!
on February 26, 2010
at 02:39 AM
Other points to consider, in addition to KetoWarrior's answer:
1) When you are upright, digestion is aided by gravity to some extent, even if you don't have acid reflux. So that's one disadvantage to digestion while asleep, unless you sleep sitting up.
2) Beyond the question of how much digestion happens at night is the question: how much digestion SHOULD happen at night? Digestion diverts blood and oxygen away from your heart and brain. When you sleep, your breathing and cardiac output are reduced. So if you eat a large meal before sleeping, too much of your body's resources could potentially be diverted to digestion, which could affect the restfulness of your sleep. Since early morning is also the highest risk time of day for heart attacks (see http://www.time.com/time/health/article/0,8599,1825044,00.html ), I want my heart as well as my brain to be as refreshed and well-rested as possible in the morning, so I try to avoid big late-nite meals.
on August 18, 2013
at 09:34 PM
Okay, if all this is true and it doesn't matter if I eat then sleep then why do I wake up with a stomach ache only if I eat beforehand?
on October 13, 2011
at 07:23 PM
You shouldn't eat before sleep. Night is detoxification time. Liver is most active at 1 AM. If you eat you will redirect big amount of energy to digestion which is needed for maintenance. Brain also does maintenance and filtering over night, and it needs energy. I don't know about practical benefits of late night sugary snack for diabetics but in normal people higher cortisol levels in the morning are desired or you can't wake up.
on January 13, 2012
at 07:20 AM
i get really bad 24 hr stomachaches if i eat and then go to bed so i know for sure its bad for you...
on October 13, 2011
at 06:14 PM
A calorie is a calorie. Deficit makes you lose, surplus makes you gain. These "new" findings (all over the internet) about full digestion going on while sleeping and late night eating has no effect on digestion, especially when weight loss is involved, I believe to be hogwash. GERD is not just an esophageal problem, it's a lack of enzyme production to process that acid, hence the reflux from acid sitting in the stomach. Why doesn't digestion take care of that? Because it slows to a crawl while sleeping. It seems a no-brainer that we slooooowww down when we sleep. Why would our blood flow, heart rate and many other functions slow down but our digestion stay perky? Ask almost any girl about feeling bloated in the morning after eating at night. I also believe boys are different than girls, hence their metabolism is much keener than girls, so they may be able to get away with meals at night. When I eat at night, my tummy rumbles before going to sleep. If I wake in the night, no grumbling. When I wake up (still lying in bed) in the am, the grumbling starts again. Hence, I was still digesting before sleeping, hardly any digestion while sleeping, and back to digesting when waking. Bottom line is, when I eat within 4 hours of going to bed, I have a big tummy...if I don't, it's flat. If that's not because of digestion, then what is it?