Why do you want to sleep after dinner? Top 5 Reasons

“After a hearty din­ner, accord­ing to the law of Archimedes, it is sup­posed to sleep …”, and also “Well, you ate — you can sleep …” — most of our com­pa­tri­ots know these pop­u­lar phras­es for sure. And after all who would argue! After din­ner, he often gets sleepy … For some rea­son, this is espe­cial­ly acute in the work­place after return­ing from the din­ing room. Med­AboutMe found out what caus­es after­noon sleepi­ness and how to deal with it?

1. Digestive processes that cause drowsiness

In the process of diges­tion, food is bro­ken down into sep­a­rate mol­e­cules — fats, pro­teins and car­bo­hy­drates, which are used by the body for dif­fer­ent pur­pos­es. Dur­ing the process of sat­u­ra­tion, the body pro­duces var­i­ous hor­mones that acti­vate and enhance the feel­ing of sati­ety. And the hor­mone insulin is need­ed so that glu­cose from the blood gets inside the cells and can be used as an ener­gy source.

For prop­er and effi­cient diges­tion, in par­tic­u­lar, such an impor­tant hor­mone and neu­ro­trans­mit­ter as sero­tonin is required for us. But the same hor­mone is involved in the acti­va­tion of slow-wave sleep. Drosophi­la fruit flies gen­er­al­ly fall asleep when sero­tonin increas­es. Of course, we are far from flies, but also, thanks to sero­tonin, we begin to suf­fer from drowsi­ness when its con­cen­tra­tion in the blood increas­es.

There is also an opin­ion that anoth­er hor­mone, mela­tonin, which is respon­si­ble for night­time sleep and gen­er­al­ly reg­u­lates cir­ca­di­an rhythms, is to blame for after­noon sleepi­ness. It is just pro­duced by our body from sero­tonin. It would seem log­i­cal: more sero­tonin — more mela­tonin — that’s drowsi­ness. But with mela­tonin, not every­thing is so straight­for­ward. By itself, mela­tonin does not acti­vate the sleep process, but it pre­pares the body for it and pro­longs the state of sleep. And the pro­duc­tion of mela­tonin does not depend on the amount of sero­tonin, but on the length of day­light hours.

Anoth­er impor­tant point: if too much is eat­en, the body redis­trib­utes resources towards the diges­tion of food, tak­ing them from organs that, in its opin­ion, cur­rent­ly need it less — from mus­cles, for exam­ple. At the same time, blood flow increas­es to the fol­low­ing organs: stom­ach, intestines, liv­er and pan­creas. As a result, a per­son feels tired, relaxed and com­plete­ly unwill­ing to move any­where and do any­thing. He wants to lie down and sleep.

Flu­id intake with meals also plays a role. Too lit­tle flu­id leads to a state of dehy­dra­tion, low blood pres­sure and increased drowsi­ness. Too much liq­uid neg­a­tive­ly affects the diges­tion process.

How to eat so as not to fall asleep after eat­ing? First of all, don’t overeat! It is bet­ter to have a cou­ple of very light snacks than one full three-course meal, dessert and a glass of sweet tea.

2. “Sleepy” foods

And sero­tonin is pro­duced from the essen­tial (that is, we don’t know how to make it our­selves) amino acid tryp­to­phan, which must get into the brain tis­sue for this. There is a lot of it, for exam­ple, in turkey meat or in egg white. But the love of a turkey or egg white does not guar­an­tee patho­log­i­cal drowsi­ness — there are a num­ber of bio­chem­i­cal nuances that do not allow a direct rela­tion­ship between a piece of turkey and the desire to sleep.

The list of foods rich in tryp­to­phan also includes: spinach, soy, cheese, tofu, cod, pork, and even bananas — that’s def­i­nite­ly not some­thing you should snack on, espe­cial­ly if you have to trav­el as a dri­ver.

How­ev­er, a min­i­mal “drowsy” effect is pos­si­ble. And it increas­es if tryp­to­phan enters the body in com­bi­na­tion with glu­cose: this acti­vates the process of insulin secre­tion, and the tis­sues begin to absorb more amino acids — more tryp­to­phan is in the brain tis­sues.

To reduce the risk of day­time sleepi­ness, you should not eat the above foods in the mid­dle of the work­ing day.

3. Lack of sleep

All of the above “food” effects that cause drowsi­ness are great­ly enhanced if a per­son is in a state of sleep depri­va­tion, and espe­cial­ly — a chron­ic lack of sleep. When a per­son does not get enough sleep on a reg­u­lar basis, his body catch­es any moment of relax­ation in order to put its own­er into rest mode and get the miss­ing sleep.

It is impos­si­ble not to add: day­time sleep itself is not so bad! More­over, NASA experts claim that a 10–20-minute nap dur­ing the day increas­es a person’s alert­ness and per­for­mance, increas­es reac­tion time, atten­tion and mem­o­ry.

And a 2021 study pub­lished in the British Med­ical Jour­nal found that in old­er adults 65+, short naps reduce the risk of demen­tia.

A healthy activ­i­ty and rest reg­i­men, 7–8 hours of sleep a night will reduce the risk of devel­op­ing day­time sleepi­ness — or at least give strength to fight it.

4. Lack of physical activity

Reg­u­lar phys­i­cal activ­i­ty helps to keep your­self in a cheer­ful state of mind even after a hearty meal. Train­ing ener­gizes you for the whole day, pre­vent­ing you from falling into sleep and feel­ing tired. Just relax­ing at home on the couch does not give such an effect. In the absence of reg­u­lar phys­i­cal activ­i­ty and a seden­tary lifestyle, there is noth­ing to oppose the feel­ing of day­time sleepi­ness.

But at the same time, exces­sive loads can have the oppo­site effect and cause all the same drowsi­ness. If in the mid­dle of the work­ing day you go to the gym with “iron” and work there to the lim­it, then the body will right­ly judge that recov­ery is much more impor­tant than office activ­i­ties. And after a tight snack, drowsi­ness will flood over with the “ninth wave”.

So if you’re doing a sport in the mid­dle of the day, it should be ener­giz­ing, not drain­ing you dry.

5. Diseases that cause drowsiness

Drowsi­ness after eat­ing and in gen­er­al for any rea­son can be one of the symp­toms of a num­ber of dis­eases:

• dia­betes. Oth­er symp­toms: dizzi­ness, weak­ness, con­stant feel­ing of hunger, irri­tabil­i­ty, peri­od­ic “fog in the head”;
• hypothy­roidism. Oth­er symp­toms: chron­ic patho­log­i­cal fatigue, weight gain, chill­i­ness, brit­tle hair and nails;
• sleep apnea. Oth­er symp­toms: chron­ic lack of sleep, fatigue, headaches;
• ane­mia. Oth­er symp­toms: fatigue and weak­ness, prob­lems with con­cen­tra­tion, sleep dis­tur­bances, appetite, decreased libido, headaches, tin­ni­tus, pal­lor, pal­pi­ta­tions;
• some types of food intol­er­ances and food aller­gies. Oth­er symp­toms: dis­or­ders of the gas­troin­testi­nal tract (nau­sea, vom­it­ing, diar­rhea), skin man­i­fes­ta­tions of aller­gies;
• postin­fec­tious asthe­nia. This is a state of con­stant fatigue and a desire to lie down to rest after any event, includ­ing after eat­ing. It has been known for a long time — some peo­ple suf­fer from post-infec­tious asthe­nia after the usu­al flu, but they have become more talked about in the cur­rent pan­dem­ic. It turned out that COVID-19 often leads to the devel­op­ment of post-COVID syn­drome.

If there are oth­er symp­toms that give cause for con­cern, you should con­sult a doc­tor and under­go an exam­i­na­tion. It is pos­si­ble that the prob­lem can be solved by treat­ing the under­ly­ing dis­ease.