Lan is a proud mother who grew up in Wellington and graduated with a Bachelor of Science in ecology from Massey University before moving to the South Island to work for the Department of Conservation in freshwater ecology, which prompted an interest in freshwater fish. She completed a Master of Science in ecology at the University of Otago.

Lan was elected to the Canterbury Regional Council at the 2016 New Zealand local elections and was selected by the Green Party to contest the Banks Peninsula electorate at the 2023 New Zealand general election.