Minimum: key ring, wallet, S&W 340 (15 ounces loaded) or Kahr PM-9 (19.4 ounces loaded), cell phone, mini-Spyderco. Commonly included: Bianchi speedstrip with 5 rounds of .38+Ps and 1 CCI .38 shot load, Key Defender OC spray. (Reloads and/or pump shotguns typically not far away.)
"Elevated risk" days: All of the above and/or Glock 29. 2-ounce Fox OC.
"High risk" days: I try not to do those anymore. Since roughly the age of 40, the brain seems to have gotten bigger and the balls smaller.
So yea, a lighter load.