Original sentence: <ref=vegan/> He reached the top of his career aged thirty on a vegan diet<ref=vegan/> which he has claimed is better suited to him because he can eat a larger quantity without affecting his athleticism<ref=vegan/> and he believes that switching to a vegan diet can lead to improved athletic performance.<ref=vegan></ref>
Edited sentence: He reached the top of his career aged thirty on a vegan  diet which he has claimed is better suited to him because he can eat a larger quantity without affecting his athleticism  and he believes that switching to a vegan diet can lead to improved athletic performance