Participants expecting to have a conversation with an obese student were much quicker to indicate that words like “powerful”, “strong” and “dominant” matched their self-concept than were participants expecting to have a conversation with a normal-weight student. …  Moreover, participants expecting to chat to an overweight student reported feeling more socially powerful as revealed by their agreement with statements like “I could make the interaction more enjoyable for my partner” and “I expect that my partner will like me more than I like him”. Finally, participants waiting to talk to an overweight partner also tended to rate their partner more negatively, and were more likely to say that obesity is due to lack of willpower.

More here.  Humans clearly attend closely to status, an important part of status is dominance, and a key way we show dominance is to tell others what to do.  Whoever gets to tell someone else what to do is dominating, and affirming their own status.  But we are also clearly built to not notice most of our status moves, and so we attribute them to other motives.  And as long as we are making up motives, we might as well make up the most admired of motives, altruism.

So we tend to think we tell others what to do in order to help them, and not to dominate them.  In particular we tend to think we tell fat folks what to do, and control their behavior, because this will help those fat folks.  For example, many support taxing soda or fast food in order to help fat folks.

Yet it is completely crazy to imagine that fat folks have not yet heard that fat might be unhealthy or unattractive.  Believe me, they’ve heard!  If they are choosing to be fat, they are doing so reasonably informed of the consequences.  Our constant anti-fat “public health” messages are not at all kind – such messages just serve to put fat folks down, and lift the rest of us up.  If anyone is so clueless as to need constant reminders, it is those who can’t see their own over-bearing domination, such as putting down fat folks to lift themselves up.

Hat tip to Stefano Bertolo and Tyler Cowen.