Effects of Eating (Overweight vs Underweight) and proper clothing (Stats)

Note that the  rates were got with using the correct clothing for the temperature. 

I started as underweight and ate 1 Prime Beef waited 5 minutes and switched lobby and repeat to gain weight. Weight is gained and lost in .75% increments.

Underweight gives you from -7.5% to -5.25% Stamina Drain Rate and +7.5% to +5.25% Damage Absorption depending on how underweight you are (7.5% being a the lowest weight). Also gives you a 125% Core Drain Rate.

Average (leaning to underweight side)  gives you -4.5% to  -.75% Stamina Drain Rate and +4.5% to +.75% Damage Absorption depending on how close to underweight you are. Also gives you a 100% Core Drain Rate.

Perfect gives you a 0% Stamina Drain Rate and 0% Damage Absorption. Also gives you an 85% Core Drain Rate.

Average (leaning to the overweight side) gives you a +.75%  to +4.5% Stamina Drain Rate and -.75% to  -4.5% Damage Absorption depending on how close to overweight you are. Also give you a 100% Core Drain Rate.

Overweight gives you a +5.25% to +7.5% Stamina Drain Rate and -5.25% to -7.5% Damage Absorption depending on how overweight you are (7.5% being at maximum weight). Also gives you a 125% Core Drain Rate.

Clothing 

If you are wearing the correct clothing (Fair temperature for your toon) you get a All Cores Drain Rate of 0%. If your toon is Hot or Cold you will get a All Cores Drain Rate of +900%