What is the cause of my weight gain?

I have always been relatively thin, but I've gained around 15 lbs in the last 18 months despite no lifestyle change. I brought it up to my general doc, but was told that my metabolism is probably changing due to age. I don't buy this explanation.

I did an horary last night. I believe my horary is telling me something.

I am Mercury in Detriment in the 4th house. My 6th house of illness is fixed Aquarius Saturn applying in a conjunction to Mercury also in the 4th. South node is also in the 6th in an applying conjunction with Venus. My Moon is in 8th in Aries.

I can't figure out what the 4th house represents, other than perhaps something hidden?? Although Jupiter is associated with weight gain, so it makes sense that Mercury and Saturn are there. I think the Moon in my 8th in Aries could mean reproductive organs, uterus or a reproductive hormone. Saturn tells me there's a chronic or long-standing component to this, while Mars means acute. My Venus conjunct the South Node could also relate to reproductive organs or my neck.

In general, I don't feel ill, but something is off.

I have trouble putting all this together and would appreciate feedback.

yeah that bloody merc is getting to be a bit too ridiculous

it is critical deg
detriment
and fall

i have to say it is osmething to do with the diet

venus rules food
and merc is not friends with venus atm
venus strong pisces overeating condition NOT saying you are overeating but the exalted planet is too much of a good thing.
it has to be the diet

Thanks for the feedback. Food and weight gain do go hand in hand.

I'll work at revising my diet. Perhaps I'm getting too much of one certain thing.