Culture is an extremely important factor when determining anything with Healthcare. Someone's culture may have them for example; refuse medications, prioritize home remedies, or claim vaccines cause autism (yes it has caused a cultural phenomenon). This hold true especially for diets.
Someone's culture may make certain food you suggest unable to be followed through on, or misconceptions. Sometimes a cultures diet relies heavily on some foods that are recommended. This ultimately culminates in the fact that one needs to understand cultural aspects in order to come up with successful diet plans and or compromises.
A carcinogen is defined as an agent (e.g. chemical) that can increase the risk of cancer. Exposure to the carcinogens present in tobacco smoke increases the risk of developing cancer. It causes lung cancer. Hope this helps!