Vha16-1m2/Vha16-1m2 flies show starvation resistance (prolonged survival under food-deprived conditions) compared to wild type. Around 56% of Vha16-1m2/Vha16-1m2 flies show diminished midgut acidity (compared to 19% in controls). Vha16-1m2/Vha16-1m2 flies have further diminished midgut acidity when fed acetazolamide (similar to wild type). Vha16-1m2/Vha16-1m2 flies have elevated levels of triglycerides and significantly increased bodyweight compared to wild type. Feeding rate and egg production in mutants is similar to controls. Vha16-1m2/Vha16-1m2 flies have a shortened lifespan compared to wild type under normal conditions.