What does your dog eat?I have lost about 5kg of fat, I am not saying you can’t put on weight being vegan, you definately can.
But for me, I found that after dinner of lots of meat like I used to eat, I would feel sluggish for the rest of the night.
But, since cutting out meat It’s like my body digests my dinners easier, so I have more energy in the evenings and tend to take my dog for a walk or be active in other ways rather than just sit in front of the tv.
This flows on to other benefits to, having the energy to exercise etc increases consentration, and I find I read better than I used to at night.