I have always been curious about the cost of foods based on their protein contents. It is easy on the surface to see how much protein comes from a certain protein source, but I wanted to get a little more information. Since this may be of some use to others I have decided to put it here. Let me know if there are any blatant problems.

This article will take a look at common protein sources and look at the cost as it relates to the quantity of protein. I will look at both the cost per gram of protein and the protein density. The reason I am including protein density (grams of protein per pound) is to get an idea of the quantity that would need to be consumed in relation to other food sources.

I have chosen to look at 6 different and common protein sources here: protein powder, chicken breast, 75/25 ground beef, 93/7 ground beef, whole eggs, and egg whites. I will probably be updating with more foods in the future. Let me know of any requests.

Protein powder

I did not want to get into the whole debate about quality of protein powders, protein sources in the powder and so forth. So for this comparison I simply chose the bestselling protein powder on bodybuilding.com, Optimum Nutrition 100% Whey Protein. Since most people buy this in the 5lb tub size I will use the cost of $43 for 5lbs. Note this is neglecting shipping costs.

Optimum Nutrition Protein Powder has approximately (depending on the flavor) 77 servings, each of 24g Protein. Total protein content is therefore 1848g protein. This yields a cost per gram of protein: $0.023268. Protein density: 370g/lb.

Chicken Breast

People love chicken breast for protein, relatively low in fat and cheap. The price of chicken breast can vary greatly on the type, quantity, and sales. I have decided to use a price of $2.20 per lb. This is kind of a middle of the road price.

Chicken breast has an average protein content of 27g per 4oz serving. This means a pound of chicken breast has about 108g protein. This makes the cost per gram of protein: $0.020370. Protein density: 108g/lb.

Ground Beef

The price of ground beef varies wildly mainly depending on the fat content. For that reason I chose to take the 2 extremes, the cheapest (75/25) and the more expensive, but still commonly available 93/7 cut. In case you are unaware these numbers are the percentage of fat to the meat, so 75/25 is 25% fat 75% meat. As an aside remember that this is by weight (not calories) so with meat being 4 calories/gram (protein and trace carbs) and the fat being 9 calories/gram this cut has 43% of the calories from fat. 93/7 is about 14% calories from fat.

75/25 ground beef usually goes for approximately $2/lb. And 93/7 often goes for around $3/lb.

75/25 ground beef has a protein content of about 70g/lb. This makes the cost per gram of protein $0.028571. Protein density: 70g/lb.

93/7 ground beef has a protein content of about 88g/lb. This makes the cost per gram of protein $0.034091. Protein density: 88g/lb.

Eggs

Eggs are cheap and egg protein has a high biological values so people like them. Eggs can vary greatly in price depending mostly on the conditions in which the chicken was raised. I will assume you are getting the cheap large ones for this comparison. A dozen of these eggs usually goes for around $1. I will also assume you cook them.

Eating the whole egg (white and yolk) yields about 72g protein per dozen (and 60g fat & 2544mg cholesterol if you are interested). This makes the protein cost $0.013889 per gram. Protein density: 55 g/lb.

If you eat just the egg white you get about 48g protein per dozen (and only trace fat & cholesterol). Protein cost is therefore $0.020833 per gram. Protein density: 55g/lb.

Summary

This actually turned out a little different then I expected. You can certainly understand why people like chicken breast for protein. Chicken breast is the cheapest source next to whole eggs. But since whole eggs contain a great deal of fat at nearly half the protein density (you would have to eat about 2x as much by weight) it seems chicken breast is a best buy.

I did find it surprising how cheap protein powder is based on the cost of protein alone. And the fact that lean ground beef is actually quite expensive relative to the protein content.

Let me know if you want any more sources to be added!