Korva is a scroll of the internet’s best ideas.
Total protein beats meal timing
The rat study
The setup held calories, nitrogen, and macros identical, using whey protein. In one group, every meal cleared the threshold for stimulating muscle protein synthesis. In the other, the first two meals fell below it. There were 110 animals, and every meal for every animal was weighed out by hand at 6:00 AM, noon, and 6:00 PM for 11 weeks.
Where protein goes
Hind limb muscles were a little larger in the evenly fed group, a small but significant difference, and the animals eating one high-protein meal had bigger livers. Skeletal muscle turns over at about 1% a day, so it takes about 100 days to replace, while the entire gut turns over in two to three days and the liver is among the most metabolically active organs. A big protein meal may feed those tissues while skeletal muscle protein synthesis caps out.
Human studies
In humans, a couple of Grant Tinsley studies used 16/8 intermittent fasting with training inside the eating window and at least three protein-containing meals, and found no difference in lean body mass compared with eating whenever. More extreme forms, such as alternate-day fasting or 20/2 and 20/4, show differences in lean body mass in some studies, though hard resistance training can offset much of that. Getting enough total protein remains the larger lever.
Why does the gut turn over so fast?
The lining of the small intestine is replaced about every three to five days. Stem cells at the bottom of small pockets called crypts divide constantly, and new cells migrate up toward the tips of the villi. This renewal keeps the lining healthy against acid, enzymes, and microbes. The process makes the gut one of the most protein-demanding tissues per gram.
What does the liver do with extra protein?
The liver strips nitrogen from amino acids and converts it to urea through the urea cycle, which the kidneys excrete. The carbon skeletons left over can be burned for energy or turned into glucose. This lets the body process large protein meals without storing the protein itself. Hans Krebs and Kurt Henseleit described the urea cycle in 1932.
How much protein does one meal use for muscle?
In a 2009 study in the American Journal of Clinical Nutrition, Daniel Moore and colleagues at McMaster University gave young men different amounts of egg protein after resistance exercise. Muscle protein synthesis rose with dose up to about 20 grams, with no larger increase beyond that. The extra protein was oxidized instead. The study tested young men after a leg workout.
More from Andrew Huberman
