A 5-lb tub of whey protein concentrate (80 servings) costs $35–$55; premium isolate and plant-based proteins run $50–$80. Amazon, Bodybuilding.com, and Costco offer the best price per gram.
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About Protein Powder
Popular models: Optimum Nutrition Gold Standard 100% Whey ($59 for 5lb), Dymatize ISO100 ($59 for 3lb, isolate), Garden of Life Organic Plant Protein ($39 for 1.1lb), and Bulk Supplements Whey Concentrate ($44 for 2.2lb).
Best deal: Optimum Nutrition Gold Standard Whey 5-lb tub ($49–$59 at Amazon, often cheaper at Costco) is the most consistent price-per-gram value — 24g protein, 5.5g BCAAs, and a trusted 30-year brand.
Premium pick: Dymatize ISO100 ($59 for 3lb) uses hydrolyzed whey isolate — the fastest-absorbing protein, essentially zero lactose, and best for post-workout in lactose-sensitive individuals.
Where to Buy Protein Powder
Amazon, Bodybuilding.com, Costco, GNC, Walmart The comparison above covers the major retailers so you can review options before buying.
Common Questions
Whey concentrate vs isolate — which should I buy?
Concentrate (80% protein, ~$0.70/serving) is the best value for most people; isolate (90%+ protein, ~$1.10/serving) is better for lactose-sensitive users and strict macros.
How much protein do I actually need per day?
Research supports 0.7–1g of protein per pound of bodyweight for muscle building; most people eating a balanced diet need less than they think from supplements.
Is plant protein as effective as whey?
Plant blends (pea + rice) are nearly as effective as whey when leucine content is matched. Whey still edges plant protein for muscle protein synthesis speed.
When is the best time to take protein powder?
The 'anabolic window' is largely overstated — total daily protein intake matters more than timing. Pre- or post-workout are both fine; protein before bed supports overnight synthesis.