To put this into perspective, let's look at what the 75 pounds of fat that I lost looked like.
In terms of size, since each pound of fat is roughly 2 cups, we're talking 150 cups of fat, or 9 gallons. For you in metric land, that would be about 35 liters. For reference, here are 9 gallons of milk:
Holy cow! How could I have packed 9 gallons of fat onto my frame? After all, I was only 75 pounds overweight, it wasn't as if I weighed a ton or anything. Here's a superimposed side image showing me before and after my weight loss:
The red area shows my "before" dimensions, so you can see that most of my fat was stored around my stomach and thighs. Not terribly scientific, but you get the idea. The body is really good at distributing a lot of fat evenly around those areas.
What is the effect of 75 additional pounds on life expectancy? According to Science Daily, someone with moderate obesity can expect to live 3 less years, so instead of 79 years (average for the US), I might only live 76 years. Severly obese individuals might cut up to 10 years off their life.
Since I was moderately obese, 3 years is 1095 days, or 26,280 hours or 1,576,800 minutes. Granted the last years aren't always the best years, but they can be enjoyable. I would have missed many important moments with my family.
What about the economic toll of being overweight? Forbes reports that while difficult to measure, a man who is overweight might pay an additional $432 a year in various costs. Assuming I was overweight from the time I was 25 until my shortened life expectancy of 76 years, the cost is $22,032. Not so bad you say - $22k for a life of gluttony sounds reasonable! But if I had saved and invested that money at 7% annually for 51 years, I would have made $200k. That's real dough. For truly obese men, the number is $2,646 per year. With the reduced life expectancy of 69 years, that would be $116,424. With the 7% investment, $753k. Uh, this is starting to hurt.
Besides the above, there are findings that being overweight or obese can increase your chances of contracting cancer, increase infertility rates, make sleep harder (I had just been diagnosed with sleep apnea), increase chance of bullying and potentially lower paychecks. The list goes on, and on, and on.
So you tell me if all of this is worth it to sit around and eat what you want. For me, it isn't.