I'm 25 net carbs a day, or I'll gain.

What works for one doesn't necessarily work for another. Or like my father used to say, “One man's meat is another man's poison.”

If you look at pictures of youth from the 50s, 60s and 70s, before the low fat/high carb diets, you will notice they are quite a bit slimmer than today's youth. That should tell you something.