Something is wrong with how I’m going to age

I’m in my 30’s now. I’m about 5’10, about 172 pounds, pretty good athlete. I stood next to my dad last week and realized how tall he is. He’s about 6’2. He was a great athlete as well in his day (basketball player) but he is currently about 250 pounds? <br><br>My grandfather had a severe weight gain of 30-40 pounds in his 30’s and his knees couldn’t even support his own weight anymore. He had to essentially use a cane his entire life to walk. <br><br>I can’t explain why, but something about this doesn’t make sense. All my ancestors for hundreds of years (forgot the exact number my professor told us, but hundreds of years) were still walking around at 80 years old. This is unacceptable and very rare to see in my family. <br><br>I just can’t explain why after hundreds of years, we start to fall apart in the last 50?