When hubby has a lot of cow’s milk, his prostate gets swollen. It’s been the case since 35-40yo, maybe earlier. With him and two teens in the house it’s good we shop at Costco.

Anecdotally, as women age we can develop dairy and wheat sensitivities. It may be a general aging symptom as much as gender-hormone related. Milk has been easy enough to avoid to see if I feel better, it may be worth a try if someone’s having symptoms. Wheat otoh is everywhere.
On one hand it’s easy to look for healing peptides, but be cautious with your buddy’s father as they often encourage cancer growth. The growth warnings seem easy to find.
For yourself (and other guys with general prostate swelling, malaise) healing peptides may be a preventative move since there’s no cancer to feed. Some people stay on low dose GLP-1s for the anti-inflammatory benefit.