stinky bed

[dizziedumb]

i've been with my partner for years, but in the last month or two both of us have been noticing a wicked funk on his side of the bed. it's like an excretory smell mixed with sweat, almost buttery smelling, but butter gone bad. it makes me nauseous, that's how bad it is. i've been washing the sheets about twice a week since it started. i am wondering what the culprit could be, and if anyone has ideas. there are no prescription meds involved, his diet hasn't really changed, and his hygiene is pretty good. the only thing i can think of is that he's been taking GABA for mood stability since about may, he takes a regular men's multivitamin, and he also takes an herbal capsule to reduce anxiety (no garlic, valerian root, or other obviously stinky substances included). around the time that the stinkies started i also had gotten a foam topper for the bed. i wonder if the GABA might be excreting from his pores at night, and it's compounded by a warmness from the foam topper (it doesn't make me warm at all)?

any ideas for why this is happening, how to stop it, or at least combat it?