Protein head-to-heads · July 2026
Canned tuna (in water) vs Whey protein (1 scoop): which protein is cheaper?
USDA macros joined to current US grocery prices, reduced to the two numbers that decide it: dollars per gram of protein, and protein per calorie.
Whey protein (1 scoop) is 1.4x cheaper per gram of protein ($0.031/g vs $0.042/g), while Canned tuna (in water) is the leaner choice at 22.4 g protein per 100 kcal against 20.0 g. Budget favours one, a calorie cap favours the other.
| Food | $/g protein | 30 g protein costs | You need | kcal that come with it | Protein/100 kcal |
|---|---|---|---|---|---|
| Canned tuna (in water) | $0.042 | $1.27 | 115 g | 134 kcal | 22.4 g |
| Whey protein (1 scoop) | $0.031 | $0.94 | 38 g | 150 kcal | 20.0 g |
Full macros, per serving
| Food (per serving) | Price | kcal | Protein | Carbs | Fat |
|---|---|---|---|---|---|
| Canned tuna (in water) (100 g) | $1.10 | 116 | 26 g | 0 g | 1 g |
| Whey protein (1 scoop) (30 g) | $0.75 | 120 | 24 g | 3 g | 1.5 g |
A week of protein from each
Hitting a common 100 g/day protein target from whey protein (1 scoop) alone costs $21.88 a week; from canned tuna (in water) alone, $29.62. That is a gap of $7.74 every week for the same protein. In practice you mix sources: the planner computes the cheapest mix for your exact target and calorie cap, live from the same dataset.
Budget says one, calories say the other
Whey protein (1 scoop) costs $0.031 per gram of protein against $0.042, so it saves $7.74 a week at a 100 g/day target. Canned tuna (in water) answers a different question: 22.4 g of protein per 100 kcal against 20.0 g, which is what matters once calories, not dollars, are the thing you run out of first.
Compare against other foods
- Canned tuna (in water) vs Oats (dry)Whey protein (1 scoop) vs Oats (dry)
- Canned tuna (in water) vs Peanut butterWhey protein (1 scoop) vs Peanut butter
- Canned tuna (in water) vs Lentils (cooked)Whey protein (1 scoop) vs Lentils (cooked)
- Canned tuna (in water) vs Tofu (firm)Whey protein (1 scoop) vs Tofu (firm)
- Canned tuna (in water) vs Black beans (cooked)Whey protein (1 scoop) vs Black beans (cooked)
- Canned tuna (in water) vs Greek yogurt (nonfat)Whey protein (1 scoop) vs Greek yogurt (nonfat)
- Canned tuna (in water) vs Eggs (~2 large)Whey protein (1 scoop) vs Eggs (~2 large)
- Canned tuna (in water) vs Chicken breast (raw)Whey protein (1 scoop) vs Chicken breast (raw)
Frequently asked
- Which is cheaper for protein, canned tuna (in water) or whey protein (1 scoop)?
- Whey protein (1 scoop), at $0.031 per gram of protein against $0.042 for canned tuna (in water) (July 2026 US grocery prices). A 30 g protein serving costs $0.94 vs $1.27.
- Which has more protein per calorie, canned tuna (in water) or whey protein (1 scoop)?
- Canned tuna (in water), with 22.4 g protein per 100 kcal against 20.0 g for whey protein (1 scoop), 1.1x leaner. That matters when you are cutting and calories are the binding constraint.
- Which should I buy, canned tuna (in water) or whey protein (1 scoop)?
- Depends on your constraint. On a tight budget with room in your calories, whey protein (1 scoop) is cheaper per gram of protein. On a calorie-capped cut, canned tuna (in water) gives you 1.1x more protein per calorie and is usually worth its $0.042/g price.
Prices are representative US grocery prices as of July 2026; your store will differ. Educational content, not medical or dietary advice. Dataset: free download, CC-BY.