Certain factor has greater impact on child health than smoking and drinking

An unexpected factor would have a greater impact on children's health than smoking or alcohol use. This is evident from a recent report from the source. It concerns an aspect of lifestyle that often receives less attention, but plays a major role.
According to the source, there is increasing attention for the impact of this factor on health. It could be a daily habit or environmental factor that plays a major role in the development of children.
The source emphasizes that parents should be more aware of this. It is an often underestimated aspect, but it visibly affects health. However, it remains unclear what exactly this factor is.
This message is a summary based on the mentioned source and is not medical advice. In case of complaints, always consult a doctor or pharmacist.