Introduction Systemic exposure to fluoride is a significant challenge for global public health; this is because although fluoride prevents dental caries, prolonged exposure to high concentrations can cause adverse effects on various organs and systems, especially the teeth. Despite the existence of preventive strategies to reduce this exposure, evidence on the effectiveness of multicomponent interventions is limited. This protocol describes the design of a randomized controlled trial to evaluate the effects of a multicomponent intervention on parents and children to reduce the risk of exposure to high concentrations of fluoride in children.

Methods This is a randomized controlled trial, and kindergartens in the municipalities of the Department of Huila, Colombia, will be recruited. The intervention group will receive a comprehensive five-component program: installation of water filters to reduce fluoride consumption; educational sessions for parents and children to raise awareness and promote healthy practices; outreach activities to strengthen collective knowledge; and a maintenance phase to ensure the program's sustainability. In contrast, the control group will participate in a conventional educational strategy focused on the parent-child dyad. Measurements will be taken at four points in time: pre-intervention for baseline and post-intervention at 3, 6, and 12 months. The evaluation of results includes the concentration of fluoride in children's urine, fluoride levels in water (to validate the effectiveness of filtration), and changes in parents' knowledge, attitudes, and practices.

Discussion The trial will evaluate the effectiveness of a multicomponent intervention aimed at parents and children to reduce the risk of fluoride exposure. Through integrative methodological approaches and objective measurements, it will demonstrate significant improvements in reducing fluoride exposure in children and in parents' knowledge, attitudes, and practices. It will contribute to child health programs, strengthen preventive oral health strategies with an impact on public policy, community health, and new lines of research on fluoride.

Inclusion Criteria:

• Kindergartens located in municipalities with exposure to fluoride concentrations in water.
• Have a school feeding program.
• The child must be enrolled.
• They must be registered in the school feeding program.
• The primary caregiver must be able to read.
• The caregiver must agree to participate voluntarily and sign the informed consent form.
• The caregiver must commit to attending all components of the intervention (education and collection of the child's urine sample).

Exclusion Criteria:

• Parents or children with conditions or situations that may interfere with the assimilation of the components of the strategy.
• Children who wear diapers will be excluded from the study.