A rendering of Smoothie King's new store design Source: Smoothie King From the rise of GLP-1 drugs to backlash against artificial ingredients, current wellness trends are fueling growth for Smoothie King. "There are significant industry tailwinds behind what we're doing," said Gavin Felder, the chain's president and CFO. "What we've learned is people are a lot more conscious about what choices they're making. A lot of people are focusing on protein now and on fiber and all those good things." Founded more than 50 years ago, the privately held chain takes credit for inventing the word "smoothie" and popularizing the health drinks. CEO Wan Kim, previously a franchisee for the brand in South Korea, has owned Smoothie King since 2012. Last year, the company sold a minority stake to private equity firm Main Post Partners and said the deal would help Smoothie King accelerate growth and innovation.…