I'm an astrologer and I don't personally believe in it affecting someone's physical disposition.. However, many would disagree. I'm curious why you think karma would lower one's sex drive once they lose weight. Most of the time when I hear about karma it's the western new age understanding of it so I am not extremely familiar with it as a more complex concept, and the new age version isn't something I really believe in, or that I'm at least very cautious about bringing up.. but I'm trying to understand the logic behind this
I don't think being overweight or fat means you're unhealthy, necessarily. Some people are just naturally bigger and that's it. But obviously if this is happening due to constant and compulsive overeating, it's not going to be good for the person's health.. Even someone who's skinny who's overeating might have cholesterol issues, etc.
So ever hear of the 80/20 rule? or 60/40? so if most people get hornier when loosing weight 80% of people - which I believe - and the other 20 % don't get hornier or have an erection and medical diagnosis says there is nothing wrong, then several things are at play here - Karma / Energy.
Karma - past life issue ( it could be many things I am not listing) which is cause and effect from previous life issue and is here now.
Karma - something happened / trigger / trauma now in this life. Hence the issue is now which may have been a probation from previous life. Be good or else...
Karma - shit happens, where the individual lived now, ( the ground may have been unbalanced ) health condition or operation not aware or forgot that happened to a person, medication, diabetes ? and so on.
Karma - what was said in early life or said in the past life. is here now something trigger it.
There are more which I won't list but this is what I found from talking to some "spiritualist".
I had NDE when young and my meditations are way out there.
Now a person can be fat/thin, tall /short and still get horny and have a hard on like a rabbit, there are few who are the opposite.
"new age version isn't something I really believe in," you have to give me a link for me to see what they are saying / mean.
Now there are many modalities which I am not kicking anyone down.
Some to me are white wash bs. But an individual has to find the one that is close to them, and it could be many believe it or not. Then heal from it.
Astrology, ( Chinese ) ; Feng shui, Karma and many others are not wrong but it is the person to learn to interpret them.