The U.S. Centers for Disease Control and Prevention removed verbiage from its website this week suggesting that people refrain from all vaping products during its investigation into vaping-related lung injury.The CDC previously urged people to consider refraining from the use of all e-cigarette or vaping products. Now the agency is focusing on THC-containing products.The new recommendation suggests people avoid THC-containing e-cigarette or vaping products, especially those from informal sources like friends and online dealers.The agency released a report Tuesday showing that patients with vaping lung injuries tend to get THC products from informal sources -- while nicotine products often come from commercial sources, like dispensaries and vape shops.Officials said adults using nicotine vaping products to replace cigarettes should not go back to smoking, but recommends they consider using FDA-approved ways of quitting instead.They also says people should not add Vitamin-E acetate to their e-cigarettes, stating that the thickener has been "strongly linked" to lung injury cases.