I read on the label of my whey, that there are growth factors in the mixture. Do I have to be afraid to show up in a doping test?
No. If the product was produced according to the GMP (good manufactuing practice), it is very unlikely to contain any doping listed substances. The label may state this, as whey contains naturally peptides which can be classified as growth factors. These growth factors include insulin-like growth factor (IGF)-I, IGF-II, PDGF (platelet-derived growth factor), fibroblast growth factor and transforming growth factor-β.
To maintain the naturally occurring growth peptides whey needs to be processed in a special way. The patented process involves whey cation-exchange chromatography, concentration and activation, and sterile filtration. Whey protein made from cheaper manufacturing processes may therefore no longer contain these growth peptides.