Supplement increases testicle size (Ball size) significantly

Omaga 3 fish oil works for me. Makes my balls larger and I produce more cum too. Took about 3 months to see the difference. 1000mg a day
The fish oil, rubbed on cock and balls, definitely increases precum. I haven't rubbed enough on to tell if it increases cum as well. However stay tuned.
 
Ruminant endocrine physiology can be fairly different than modern anatomical humans.

I mean… ruminants don’t even absorb glucose which is the preferred human energy source (glycogen ie stored glucose) that human gonads need to function properly. Obviously ruminants depend upon their liver’s gluconeogenesis capability and human livers also can perform gluconeogenesis but… it’s just a different game.

Fadogia Agrestis has been proven to increase the size of rat testicles… and like it or not… rats are closer to human physiology than ruminants.

Effects of oral administration of aqueous extract of Fadogia agrestis (Schweinf. Ex Hiern) stem on some testicular function indices of male rats - PubMed

High protein diets can slightly influence testosterone production… but so can low carb diets. A more or less balanced diet is one which will optimize endocrine function.

That said, fadogia agrestis, laxogenin, fenugreek, stinging nettle and Ashwaganda all have some data behind an increase in androgenic activity… even good old Korean Ginseng is powerful In that respect.

But yes, a diet high in legumes which are rich in fiber and protein can help keep insulin levels lower which is a good environment for androgenic activity.