The use of artificial sweeteners (e.g., sucralose) and certain emulsifiers in ultra-processed foods like Huel raises ongoing scientific debate regarding their long-term health impacts on gut microbiome and metabolic health.

Huel Black RTD contains sucralose, an artificial sweetener, to enhance flavor without adding calories. While deemed safe by regulatory bodies in moderate amounts, research into artificial sweeteners is evolving. Some studies suggest potential alterations to the gut microbiota, which could influence glucose metabolism and insulin sensitivity, although these findings are not universally conclusive and often come from animal studies or human trials with high doses. Similarly, emulsifiers, common in processed foods to improve texture and stability, have also been investigated for their potential impact on gut barrier function and inflammation. The collective impact of these additives within a UPF matrix is an area of active research, suggesting caution against over-reliance.