Greek yogurt vs regular yogurt: protein, calcium and sugar compared

Walk down the yogurt aisle and the choice looks simple: Greek or regular. Both start as the same fermented milk, both live in the same case, and both carry a health halo. But the numbers underneath are very different, and the difference comes down to one manufacturing step. This guide puts Yogurt, Greek, plain, nonfat head to head with Yogurt, plain, whole milk using the USDA values behind our Nutrient Density Scores, so you can see exactly what each spoonful buys you.

The headline: plain nonfat Greek yogurt scores 70 on our 1 to 100 nutrient density scale, while regular plain whole milk yogurt scores 39. That gap is mostly a protein story. But regular yogurt is not the loser across the board, and the one place it wins may surprise you.

What straining actually does

Greek yogurt is regular yogurt with much of the liquid whey strained out. Traditional yogurt is milk fermented with live cultures and left as is. Greek yogurt takes that same product and filters it through cloth or a centrifuge, removing a large share of the water along with some of the lactose and minerals dissolved in it. What is left behind is concentrated: more protein per gram, a thicker texture, and a tangier flavor because the acids are concentrated too.

Straining explains almost every difference in the comparison below. Protein is bound up in the milk solids, so it stays and gets concentrated. Lactose, the natural milk sugar, is dissolved in the whey, so a portion of it drains away. And here is the twist: a meaningful amount of calcium is dissolved in that whey too, and it leaves with the liquid.

Protein: Greek yogurt wins, and it is not close

Per 100 grams, nonfat Greek yogurt delivers 10.2 grams of protein in just 59 calories. Regular whole milk yogurt delivers 3.47 grams in 61 calories. Nearly identical calories, almost three times the protein.

Put another way, Greek yogurt gives you about 17 grams of protein per 100 calories, while regular yogurt gives you under 6. A standard 170 gram single serve container of nonfat Greek yogurt lands around 100 calories with roughly 17 grams of protein, which is more protein than many people get from an entire breakfast. This is why Greek yogurt is one of the most efficient protein sources in our entire database, and it is the main reason its density score of 70 sits so far above regular yogurt's 39.

Calcium: the round regular yogurt actually wins

Straining is a trade, and calcium is the price. Per 100 grams, regular plain whole milk yogurt carries 121 milligrams of calcium, while nonfat Greek yogurt carries 110 milligrams. The gap is modest, but it runs in the opposite direction most shoppers assume. Some of the calcium in milk is dissolved in the whey, and when the whey drains off, that calcium goes with it.

Regular yogurt also edges ahead on potassium, 155 milligrams versus 141 per 100 grams, and it retains more vitamin A, 27 micrograms versus 1. None of these are dramatic differences, and both yogurts remain solid calcium sources. But if calcium is the specific reason you eat yogurt, regular yogurt gives you slightly more of it per gram, and per calorie the two are close to a wash.

Sugar and sodium: Greek takes both

The sugar in plain yogurt is lactose, not added sugar, but it still counts on the label. Regular whole milk yogurt carries 4.66 grams of sugar per 100 grams, all of it as lactose. Nonfat Greek yogurt carries 3.24 grams, because part of the lactose drained away with the whey. Neither number is high, and both are a world away from flavored yogurts, where added sugar can multiply that figure several times over.

Sodium follows the same pattern: 36 milligrams per 100 grams in Greek versus 46 in regular. Both are genuinely low sodium foods, so this is a minor point, but the direction favors Greek again.

• Protein per 100 g: Greek nonfat 10.2 g, regular whole milk 3.47 g
• Calcium per 100 g: regular 121 mg, Greek nonfat 110 mg
• Sugar per 100 g: Greek nonfat 3.24 g, regular 4.66 g
• Sodium per 100 g: Greek nonfat 36 mg, regular 46 mg
• Nutrient Density Score: Greek nonfat 70, regular whole milk 39

What about fat? The whole milk Greek option

Fat content changes the math more than the Greek versus regular question does. Yogurt, Greek, plain, whole milk carries 97 calories and 5 grams of fat per 100 grams, with 9 grams of protein. Its density score drops to 40, right next to regular yogurt's 39, because the extra fat calories dilute the per calorie nutrition. It is still a high protein food and many people prefer the taste and staying power. Just know that the standout score belongs specifically to the nonfat version.

Which one should you buy?

Pick based on what you are optimizing for. If you want protein per calorie, nonfat Greek yogurt is the clear choice and one of the best values in the dairy case. If calcium is your priority, regular plain yogurt slightly outperforms per gram, and either one comfortably contributes to your daily target. If you cook with yogurt, regular's thinner texture works better in marinades and dressings, while Greek holds up as a sour cream substitute.

Whichever direction you lean, buy plain and sweeten it yourself. And if you want to see the full nutrient breakdown side by side, put both through our food comparison tool and check the rows that matter to you.