He Ara Oranga revealed increasing numbers of adolescents in NZ struggle with mental health issues. Although current political focus is on expanding access to talking therapies, there are not enough psychological resources to meet the demand nor has access to conventional treatments reduced the burden of mental illness. One novel approach is nutrient intervention given the growing association between poor diet and poor mental health; however, it is not always realistic to manipulate diet, particularly in teenagers. Research over a decade has demonstrated efficacy in using micronutrients to treat psychiatric symptoms, but we need to explore whether coupling this approach with technology can expand reach, reduce cost and be a more acceptable way to address mental health problems. This study aims to engage 150 mood dysregulated youth (12-18 years) via an on-line App we will develop and randomise them to micronutrients or placebo for 8 weeks to establish efficacy.