Kempen – November 01, 2026 -- Most people who train need only four supplements: whey protein, creatine monohydrate, vitamin D3 and omega-3. According to a GymBeam guide reviewed by food scientist Petr Loskot, these are the only standard-range products backed by either an approved EU health claim or an International Society of Sports Nutrition (ISSN) position paper. Everything else is fine-tuning.