There is much debate over this topic in actual athletic or bodybuilding circles because it seems like everyone in the US is a fat tub of shit. But that is because of sedentary lifestyle PERIOD. And I will explain why.
Obese morons can't seem to get their shit together enough to stop eating fucking 6,000 calories of fast food every single day and lose 50-100lbs...For christ's sake. My TEMPER flares up just thinking about some fatty claiming "It's genetic" "I have skinny friends that eat 5x more than me" "slow metabolism" All the while their BMR is 1,500 cals watching tv while eating 5,000 SMDH..
Anyone who has been muscular and lean, let's say 200+lbs and semi lean, understands the work that it takes both in the gym and the kitchen. When it comes down to it though what is easier; going from a 150lb weakling to a 220lb beast, or going from 290lb to 200lbs and 6%?
I have been both places; I started training around 180lbs skinny fat...I now sit at 230lbs @ roughly 12%. I have also gone from 230 down to 180 and been very lean thus making gains - I was 180 and chubby, and 2 years later after bulking and cutting I was 180 and 6%. It took me 2 more years to slowly get back up to 230 and I am a lot leaner than the previous time I was 230, and so on.
I take the stance that gaining weight is actually much harder than losing weight..The reason I take this stance is because if you train hard, and carry some muscle, it is MUCH harder to choke down 4,500 calories of (Meat)+(Rice, Potato, Pasta, etc.) every day...And that is what is takes for me to gain weight at 230lbs is 4,000-4,500 calories per day. On the flip side what all the fatties would have you believe is that it is damn near impossible to "diet" meaning ?? 2,500 cals a day low-moderate fat/carbs? This is THE EASIEST THING YOU CAN EVER DO !!! WTF?
Eating 2,500 cals and thus LOSING WEIGHT is by far easier than gaining weight...You eat 500cals when you're hungry and boom you lose weight...Trying to get 4,500 cals of pure foods into your throat involves eating huge bowls of bullshit when you often have no appetite at all because you ate 2 hours ago...Eating becomes some chore that you begin to loath we aint talking pizza and cheesecake here, rice pilaf and meat 8 times per day baby, yum...

Getting lean =
10am - coffee, scoop of whey...
3pm - chicken, pasta
8pm - salmon, rice
12am - beef, pasta
+ small snacks fruit almonds etc...Fresh yummy stuff 100 cal here and there for hunger..
boom 2,000-2,500 calories and feeling like a damn spry little kitten all day, never too full, never sluggish, no insulin issues etc...The easiest thing ever is losing weight. Gaining weight is the hard part. Given that you actually lift and don't sit on the couch all fucking day eating pizza.
Compare that to;
8am - shake: scoop whey, 100g oats, banana.
10am - eggs, potato (uncomfortably full)
12pm - chicken, pasta > (not hungry)
2:30pm - beef, rice (uncomfortably full)
5pm - chicken, rice > (not hungry)
7:30 - 2 tuna sandwich (uncomfortably full)
10pm - chicken, fries > (not hungry)
12am - cottage cheese.
EVERY SINGLE DAY to gain 10lbs of water, fat, and muscle in 1 year...IF you're lucky.
Gaining weight is obviously harder and therefor there is absolutely no excuse not to be at least lean. Just stop driving food down your throat emotionally, happy = pizza, sad = burger, mad = cake blah blah fatties...Losing weight is fucking immensely easy.