Food purity is also thought to include foods that do not have harmful additives such as pesticides and artificial dyes, however food purity is less stringently enforced than halal standards.
Since all halal meat must be prepared by the methods outlined under Islamic law, food products must also contain only halal ingredients.
This means that even a Muslim man is not allowed to date a woman (Muslim or otherwise).
As far as clothing is concerned, no objection should be raised against the wearing of jeans or other western clothing by women or men as long as the clothes are not too revealing or indecent.
I thank the questioner for asking this question as there are a lot of people who have a similar misconception. Islam discourages dating irrespective of the gender of the individual.
Both Muslim men and Muslim women are instructed not to date irrespective of the religion of the person they are dating.
(I am a little shy; don’t want to explain in detail what I mean by too revealing.