A doctor-approved guide emphasizes choosing sugar-free protein powders for health and fitness, prioritizing protein source, transparent ingredients, and manufacturing. Whey protein isolate is highlighted as a clean, rapidly absorbed option, virtually free of sugar, lactose, and fat when minimally processed. Experts advise against added sugars, artificial sweeteners, and fillers, noting that while plant-based proteins can be effective, blended options are often superior due to complete amino acid profiles and reduced contamination risks.