Food coma: does it affect you?

This post explains why eating may exacerbate MS-related fatigue and what you can do to counteract it.

Do you suffer from food coma or excessive sleepiness and fatigue after eating a meal?

For ‘normal people’, we call this phenomenon postprandial somnolence or the siesta syndrome. Others refer to it as the ‘food coma’. It is my anecdotal experience that people with MS, in particular, people with more advanced MS, are particularly sensitive to postprandial sleepiness and fatigue. Why?

Postprandial somnolence (PPS) is a normal state of drowsiness or lassitude following a meal. PPS is a real phenomenon and has two components: (1) a state of perceived low energy related to activation of the parasympathetic nervous system in response to expansion of the stomach and duodenum from a meal. In general, the parasympathetic system slows everything down.  (2) A specific state of sleepiness, which is triggered by the hormone cholecystokinin (CCK) that is released in response to eating and changes in the firing and activation of specific brain regions. The reflexes responsible for PPS are referred to as neurohormonal modulation of sleep through the coupling of digestion and the brain. The signals from the gut to the brain travel via the vagus nerve.

My index patient is so affected by PPS that she now only eats one meal a day; her evening meal. She does this quite late so that she can crash and sleep about an hour after eating. She is a professional and needs to be functional during the day and finds if she eats anything substantial in the day she simply can’t work because of her overwhelming desire to sleep. We have tried caffeine, modafinil and amantadine to counteract PPS, but they only had a small effect in counteracting her PPS and allowing her to work productivel. Other patients reporting this have noticed some benefit from stimulants. Interestingly, my index patient, like a few others, finds carbohydrate-rich foods particularly potent at inducing ‘food coma’

Physiologists think that not all foodstuffs are made equal when it comes to causing PPS and it appears that glucose, or sugar, induced insulin is one of the drivers of this behavioural response. I suspect this why people who fast or eat very low carbohydrate or ketogenic diets describe heightened alertness and an ability to concentrate for much longer periods of time.

The reason for doing this post is to find out how common PPS is in the MS population and to give you some simple advice to counteract it. If you suffer from PPS can I suggest you review your diet and see if you identify ways to modify your eating habits and/or diets to coounteract PPS?

  1. You could adopt the above extreme solution and only eat one meal per day. Clearly, this not for everyone and is very difficult to implement. I say this, but many of my Muslim patients report feeling so much better during Ramadan when they essentially practice this type of eating pattern.
  2. You could reduce your meal size and cut out any carbohydrates from your daytime meals. You may find this difficult because it takes time for your metabolism to become optimised for ketosis. If any of you are interested in the science of ketosis I have written a Medium post on ketogenic and low-carbohydrate diets.
  3. Some of my patients find micro-meals helpful, i.e. instead of large meals you eat multiple small snacks during the day.
  4. The judicious use of stimulants. I tend to recommend caffeine, followed by modafinil and them amantadine. Please note you should probably not take stimulants later than about 3-4 pm as they have a long half-life and can cause insomnia.
  5. Some of my patients have also reported that exercise has helped them deal with PPS. I am not sure how exercise works except by possibly lowering glucose and insulin levels and improving insulin sensitivity. The latter will reduce hyperinsulinaemia that will not only cause PPS, but is an impotant driver and component of the metabolic syndrome.

Please note that PPS will be worse if you suffer from a sleep disorder and suffer from daytime sleepiness. Most pwMS have a sleep disorder so there is little point in focusing on PPS and ignoring the elephant in the room.

If you have a few minutes to spare can you please complete this survey and let us know if you come across any other effective treatments to manage your PPS.