Does becoming an informal caregiver make your health worse? A longitudinal analysis across Europe

•Our study provides new evidence on the effect of becoming (transition situation) an informal caregiver on health status.•An immediate effect is identified on health, especially on mental health, when respondents become informal caregivers.•This effect does not remit but is maintained and even becomes stronger over time.•The findings could be helpful to identify the most vulnerable informal caregivers.•The most vulnerable would be those providing care at home and those in countries where LTC expenditure intensity is low.