Can a simple supplement speed up bone healing?

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

Inclusion Criteria: * Between 18 and 85 years old * Presence of simple closed unifocal fracture (transverse, oblique, spiral, butterfly-shaped) in a long bone which need a standard of care surgical stabilization * Presence of diaphyseal fracture of lower limb (femur or tibia, Subtrochanteric fracture are also allowed) * Presence intramedullary nail * Weight bearing as tolerated after surgery * Having signed an informed consent, understand study procedures and ability to follow them * Agreed to stop vitamin D intake for participants who take prophylactic Vitamin D Exclusion Criteria: * Treatment with vitamin D for medical purpose (Non-union, osteoporosis…) * BMI \> 30 * Open fracture * Intra articular fracture * Metaphyseal fracture * Polytrauma patient (injury severity score: ISS \>= 16) * More than one lower limb long bone fracture * Bridging plate * Fracture treated conservatively with plaster * Presence of active infection (body temperature ≥ 38°C or other symptoms) * Any sign of severe vascular compromise across the fracture site (such as compartment syndrome, presence of serious vascular damage, etc.) * Pathological fracture or diseases with a risk of recurrent falling (e.g. Parkinson's disease/syndrome, Hemiplegia after stroke, symptomatic stenosis of the spinal canal, polyneuropathy, epilepsy, recurring vertigo, recurring syncope) * Participants with known bone disease which would negatively impact on the bone healing process * Participants currently being treated with radiation, chemotherapy, immunosuppression, or steroid therapy * Diabetic participants * Daily smoker participants (cigarette or vaping containing nicotine) * Participants under cortisone intake * Participants under rheumatic medications intake * Allergy or adverse effect of food supplement composition * Unwilling or unable to take study medication * Chronic drug or alcohol abuse * Pregnant or breastfeeding at the time of enrolment * Any other investigational treatment or food supplement within 3 months.