I completely agree with eggs, now that the price has come back down. Back in 2015 it was nearly impossible to find a dozen eggs for less than $4, now they’re back around $1.20 a dozen which is definitely a cheap source of tasty protein. Eggs are expected to go up again this year, but nothing like a couple years ago, they’re estimating egg prices to rise by approximately 35% (according to the USDA). Still very affordable and delicious though.
The one other extremely cheap source of protein that I’m really surprised no one mentioned is MILK!
A gallon of milk is around $1.99, supplying 128 grams of protein at a cost of 1.55 cents per gram. A dozen large eggs @ $1.20 provide 72 grams of protein, at a cost of 1.66 cents per gram. With current pricing (using “regular” or “normal” milk and eggs, so no cage free eggs or organic milk) this gives a slight edge to milk. On the other hand eggs have a slightly higher biological value, 90-100 vs 85-95 (depending on the source you’re quoting). The numbers are close enough to say that per dollar, eggs and milk are pretty much equal in terms of quality protein and bang for the buck. Milk does have a slight advantage in that it doesn’t require cooking (technically eggs don’t either, but not too many people are fond of raw egg, and pregnant women, children, and the elderly are advised to avoid raw egg, and if the eggs aren’t pasteurized, there’s a slight risk of salmonella), so milk is a bit easier to consume, but eggs are one of the easiest foods to cook, so it’s pretty much a toss up.
Either way, milk or eggs, you can’t go wrong, both are great for anyone looking to gain or maintain muscle mass!