Her mother is Native Hawaiian scholar and activist Davianna Pōmaika'i McGregor, professor and founding member of the Department of Ethnic Studies at the University of Hawaiʻi at Mānoa.

[3] Alegado earned a BS in Biology and with a Minor in Environmental Health and Toxicology at the Massachusetts Institute of Technology, and a PhD in Microbiology and Immunology at Stanford University School of Medicine.

[8][9][10] She then shifted her focus to evolution of host-microbe interactions during her postdoctoral fellowship with Nicole King at UC Berkeley, researching multicellular development in the closest living relatives of animals, the colonial choanoflagellate Salpingoeca rosetta.

[14] Alegado has investigated the oceanic factors which influence fish yield from the traditional Hawaiian fishpond stewarded by Paepae o Heʻeia, concluding that El Niño had a major effect and that this may become more frequent with global climate change.

[6] She works with the non-profit organisation Kuaʻāina Ulu ʻAuamo to establish a process, known as 'kūlana noiʻi', which helps "researchers build and sustain equitable partnerships with the community".

[24] Alegado opposes the construction of the Thirty Meter Telescope on Mauna Kea, since it represents a continuing infringement on native lands, and has spoken out about the issue to the media.

[25] She has written to counter the idea that the native Hawaiian culture is acting 'anti-science', describing how the local philosophies that hold the mountain sacred are based on concepts of environmental protection, and stating that it is dangerous for science to continue unbounded by ethics, anti-colonialism and respect.