I went on keto and lost around 50lbs. That's without adding exercise. So it's doable. Diet is actually a lot of weight loss. Running a mile burns like 100 calories? You'd have to run 30-35 to lose 1 lbs.
Grats!
I have a friend who did keto and lost some real excess weight without changing anything else. He was doing some lifting and other "bro" type exercises already though.
Usually a combination of the two is needed to be effective. Dieting alone usually only gets you so far, and a lot of times the loss is temporary and the bounce back is worse. It can even end up getting you sick because lots of todays fancy diets are based on fully cutting out certain foods and nutrition types, which we are not built to tolerate for longer periods (talking 6+months - years).
I know some people who can eat 2 bars of chocolate, chug 6 beers, eat half a kilo of bacon with 2 bag of chips, every single day, and don't gain a pound while sitting on their asses all day. I also know a guy who can gain 6trillion pounds from drinking a single beer and having to spend 6 months dieting and exercise to lose the excess weight.
It's all genetics...
80.lv
check out the vid, the sight of a cat with trackballs sticking out of it is just priceless 
