Food coma, anyone?
It sounds as if you suffer from the common affliction of postprandial somnolence, otherwise known as a food coma. Postprandial somnolence is not completely understood in humans, although there have been experiments on rodents, fruit flies and nematode worms.
A meal filled with high-carb and high-sugar foods, such as potatoes, breakfast cereals and white bread, may be more likely to make you slump. These foods have a high glycaemic index, rapidly releasing sugars in the body.
The spike in blood glucose instructs the body to produce more insulin, which sets off a chain of biological events leading to muscle and fat cells taking up glucose. This can cause blood sugar levels to crash, leading to low energy.
When you eat, your body activates its parasympathetic nervous system and enters a ‘rest and digest’ mode, which contrasts with the sympathetic nervous system’s ‘fight or flight’ mode. The extent to which the rest and digest mode induces sleepiness depends on how much food you eat in one sitting. More food requires more rest.
The amino acid tryptophan may also play a role in postprandial somnolence. Tryptophan is present in many protein-based foods, including eggs, fish and meat. Insulin stimulates the uptake into muscle of some amino acids, but not tryptophan. This leaves tryptophan available to travel on an amino acid transporter, into the brain. There, it converts to serotonin and melatonin, both of which increase relaxation and sleepiness.
The best way to avoid a food coma is to avoid having high-carb meals, like sandwiches or rice. Add in some protein, healthy fats and vegetables to balance things out, and don’t eat too much in one sitting.
Read more:
- Why do I always get an energy crash in the afternoon?
- What happens in my body when I eat sugar?
- Do any foods help to decrease anxiety?
- Can’t stop your brain racing at 3am? Try these suggestions from a GP
Asked by: Mandy Wilson, London
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