Soy Protein vs Whey Protein: Calories and Nutrition Compared (2026)

Soy protein contains 88.3 g of protein and 335 calories, while whey protein has 66.7 g of protein and 385 calories. Soy protein is higher in protein and lower in calories.

Soy protein and whey protein are both popular protein supplements, each with distinct nutritional profiles. This comparison highlights their calorie, protein, carb, and fat content to help you make an informed choice.

What Is the Difference Between Soy Protein and Whey Protein?

Soy protein is a plant-based protein derived from soybeans, often used as a dietary supplement for its high protein content. It is suitable for vegetarians and vegans. Whey protein is a dairy-based protein derived from milk during the cheese-making process, known for its high bioavailability and rapid absorption. It is commonly used by athletes and fitness enthusiasts.

Soy Protein vs Whey Protein: Nutrition Side by Side

Below is a side-by-side comparison of the nutritional values of soy protein and whey protein per 100 g.

Nutrient (per 100 g)	Soy protein isolate	Whey protein powder
Calories	335 kcal	385 kcal
Protein	88.3 g	66.7 g
Carbs	0 g	17.9 g
Sugar	0 g	5.1 g
Fat	3.4 g	5.1 g
Fiber	0 g	0 g
Sodium	1005 mg	385 mg

Which Is Better, Soy Protein or Whey Protein?

For weight loss: Soy protein has 335 calories, while whey protein has 385 calories, making soy protein the better option for weight loss.

For muscle and protein: Soy protein offers 88.3 g of protein compared to whey protein's 66.7 g, making it the superior choice for muscle building.

For low-carb or low-sugar: Soy protein contains 0 g of carbs and 0 g of sugar, while whey protein has 17.9 g of carbs and 5.1 g of sugar, making soy protein a better low-carb option.

How to Track Soy protein and Whey protein Accurately

It's easy to misjudge portion sizes and macros when comparing protein supplements. Nutrola is an AI nutrition tracking app that identifies foods from a photo and returns calories and macros from a database of more than 1.8 million foods. It also supports barcode scanning and voice logging. Nutrola is available from EUR 2.50 per month and shows no ads on any tier.

How We Compiled These Numbers

The numbers provided are rounded reference values for educational use and should not be considered medical advice. Always consult a healthcare professional for personalized nutrition guidance. Values are per 100 g from USDA FoodData Central.

Frequently Asked Questions (FAQ)

Which protein has more protein?

Soy protein has 88.3 g of protein, while whey protein has 66.7 g.

Which protein has fewer calories?

Soy protein has 335 calories, while whey protein has 385 calories.

What is the carbohydrate content of soy protein?

Soy protein contains 0 g of carbs.

What is the sugar content of whey protein?

Whey protein contains 5.1 g of sugar.

How much fat is in soy protein?

Soy protein contains 3.4 g of fat.

What is the sodium content of whey protein?

Whey protein contains 385 mg of sodium.

Key Takeaways

• Soy protein: 335 calories per 100 g.
• Whey protein: 385 calories per 100 g.
• Soy protein: 88.3 g of protein per 100 g.
• Whey protein: 66.7 g of protein per 100 g.
• Soy protein: 0 g of carbs and 0 g of sugar.
• Whey protein: 17.9 g of carbs and 5.1 g of sugar.