I preface my comments by telling you that I used to be overweight, but am now in excellent shape.

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Corporately, there is definite discrimination.
Within the context of the Apostolic sphere, there doesn't seem to be as much. Look at some of most respected speakers in the UPC.
People, that includes sinners and saints, are definitely more attracted to people who have managed their lives well. Often, being overwieght is an indication of a lack of self-discipline/ self-control.