From time immemorial, men have loosened their loincloths, un-cinched their robes, loosened their breastplates, or unhitched their trousers so they could lie down and digest their meals. In fact, if modern-day restaurants were savvy, they'd set up cots next to the table so men could lie down after eating and maybe catch a little snooze so they could soak up their blue-plate special.
Unfortunately, it turns out that practice might not work so well when it comes to protein and blood levels of amino acids.
Don't Take It Lying Down
Dutch researchers wanted to know if lying down after a meal – as opposed to sitting or standing – affected the digestion of protein and amino acid absorption.
To figure it out, they recruited 8 healthy men. The scientists gave the subjects a drink containing 22 grams of protein and 29 grams of carbohydrates on two separate occasions. The solution was also laced with paracetamol, aka acetaminophen, to act as a kind of tracer. By tracking the absorption of the paracetamol, they could get an inkling of how well nutrients or chemicals other than protein were being absorbed.
After the subjects finished their drink, the scientists tracked their blood for 4 hours. The first time they drank their drink, the men were required to stay seated for the duration. The second time, they were asked to lie down on a bed with their feet slightly elevated (effecting a 20-degree angle).
What They Found
When the men laid down after drinking their protein/carb solution, leucine concentrations were only about 75% as high as what they were when the men remained in a sitting position.
Likewise, plasma levels of essential amino acids were only about 62% as high as they were when the men stayed upright.
The levels of paracetamol were also reduced when lying down, measuring out at only about 58% of what they were when they were sitting.
What This Means to You
The scientists concluded that, "Gastric emptying rate and post-prandial plasma amino acid availability are significantly decreased after protein ingestion in a head-down tilted position. Therefore, upright body position should be considered when aiming to augment post-prandial muscle protein accretion in both health and disease."
It seems clear that lying down after a meal interferes with the absorption of protein and all other nutrients.
It's probably easy enough to remain sitting or standing after a meal to ensure proper absorption, but what about all of us who have a protein drink/meal before beddy-bye? Or worse yet, those of us who wake up specifically at some point in the night to quaff some extra protein and then go back to bed?
There are a couple of possible solutions:
- You could either say to hell with "amino acid absorption kinetics" and just drink extra protein to compensate, or...
- You could drink Mag-10®, which is a di- and tripeptide complex that's transported directly into the bloodstream without requiring any further breakdown. A small amount, even in normal circumstances, stimulates protein synthesis far beyond what you'd get with a much greater amount of conventional protein powder or whole foods.
That way, you could largely thwart the whole impaired-digestion thing you get from lying down after a meal.
- Andrew M. Holwerda, Kaatje Lenaerts , "Body Position Modulates Gastric Emptying and Affects the Post-Prandial Rise in Plasma Amino Acid Concentrations Following Protein Ingestion in Humans." Nutrients 2016, 8(4), 221.