The endocrine system through the use of hormones
The most accurate classification of the common forms of coronary artery disease and hypertension is that they are complex disorders which result from gene-environment interactions. For example, almost 60% of CAD cases are found in South East Asia, that too when their population if just 20% of the total world's population. This is due to the environmental interactions with the genetic disposition of the people of this region.
Trans fats.
Unsaturated fat is GOOD fat, saturated fat is bad fat as well as trans fats.
The build up in the child's ear prevent sound from reaching the eardrum.