Fellow dense person here.
I was 175 lbs in high school, wearing 28-inch waist jeans. Every new doctor is perplexed when they weigh me. I can't count the number of times a doctor has weighed me, had me step off the scale, weighed me again, had me step off the scale again, weigh themselves, then weigh me again. They then shake their head, and write down the number, and tell me that the obesity charts and measurements do not apply to me.
I'm currently 230, and am mistaken for <200 usually. I can wear the same pants that my sub-200 friends wear (38-inch waist).
A lot of people try to transmogrify their fat into "heavy bone density", or some such bullshit.
The reality is that some of us weigh more. Some less. Welcome to the club.