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Optimum Nutrition Serious Mass, protein powder bag supplement product image

Optimum Nutrition Serious Mass Review

This page provides a straightforward overview of Optimum Nutrition Serious Mass Review.

  • Format and servings
  • Key ingredients
  • Value considerations
Published: 18 August 2025 · Last updated: 18 August 2025
Editorial rating: 4.5/5
50 g protein 1 250 kcal Low sugar

A calorie‑dense mass gainer for people with very high energy needs.

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Quick verdict

Serious Mass is one of the best‑known weight‑gainer shakes. Each two‑scoop serving delivers 1,250 calories, 50 g of protein and over 250 g of carbohydrates. It’s designed for those struggling to eat enough calories daily.

How we review

At Protein Pitstop, our reviews are based on editorial research — not product trials. We assess:

  • Label and ingredient information
  • Customer feedback and Amazon reviews
  • Brand transparency and certifications
  • Suitability for different dietary needs

We do not accept free products or sponsorships, and affiliate links don’t influence our results.

Nutrition & ingredients

A serving combines whey concentrate, casein and egg albumen with a carbohydrate blend of maltodextrin and glucose polymers. It also includes added vitamins, minerals, creatine and glutamine. The formula is high in sugar (around 20 g per serving) and contains lactose.

Taste & mixability

Customer reviews describe Serious Mass as sweet and dessert‑like, with Chocolate and Banana popular flavours. Because servings are large, mixing is easier with a blender. Users often split servings across the day for easier digestion.

Use cases

Serious Mass is marketed for “hard gainers” — people struggling to eat enough calories daily. Customer feedback highlights convenience and the calorie load as key benefits, but some mention digestive discomfort. Because servings are large, users often split a serving across the day for easier digestion.

Value

Serious Mass is positioned as cost‑efficient calories in liquid form. Not everyone needs this density; those wanting just protein should consider standard whey.

Pros & cons

Pros

  • 1 250 calories per serving with 50 g protein
  • Includes vitamins, minerals, creatine and glutamine
  • Convenient for high calorie intake

Cons

  • Very high sugar content
  • Large serving sizes are hard to digest for some
  • Not suitable for lactose‑intolerant users

Who it suits

Good fit if: You struggle to gain weight or eat enough calories through food.

Skip if: You want low sugar, low calorie, or lactose‑free supplements.

Alternatives

Cleaner gainer: ON Gold Standard Gainer

DIY shake: oats, peanut butter and whey protein

Lean protein: Optimum Nutrition Gold Standard Whey

FAQs

Can I use Serious Mass if I’m lactose‑intolerant?

No. Serious Mass contains whey concentrate and casein, both of which contain lactose. Lactose‑intolerant individuals should choose a dairy‑free gainer or blend their own.

Is Serious Mass healthy?

It can be part of a healthy bulking plan when used appropriately, but it’s high in sugar and should not replace balanced meals. Consider your overall diet and consult a nutritionist if unsure.

How do I mix Serious Mass?

Follow the mixing directions on the product label. Many users find a blender helpful for larger servings and prefer splitting a full serving into multiple shakes if needed.

Can women use Serious Mass?

Yes, but women typically require fewer calories than men. Adjust the serving size to your needs and monitor your caloric intake to avoid excessive weight gain.

Does Serious Mass contain creatine?

Yes, it contains a small amount of creatine monohydrate. If you’re taking additional creatine, factor this into your total daily intake.

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