People think fatty proteins simply congeal in the arteries causing clogs. This is not entirely untrue, but the real concern with heart-disease is healthy cardiac cells.
Your circulatory system can handle a good deal of clogs and blockages, so long as its cells are supplied with an appropriate amount of energy, water and nutrients. Why do you think all the recent reports about obesity and cancer rates are the latest concern. Because a chronically obese lifestyle simply leads to unhealthy cells. Why? Not enough resources/per-cell.
They say you should drink eight glasses of water per day. We don't actually know if that's true, but we know the correct number isn't zero glasses. It could be ten, but for the sake comfortably making my point, let's be conservative and say an adult of healthy body mass needs six glasses a day in order to keep all his cells adequately hydrated to the point where he will live a natural full life-expectancy. (You can get water other ways such as veggies, but the average American diet has way more incidentals which dehydrate rather than hydrate.)
The BMI chart say a 5'10" male should weigh 150 lbs. He needs six glasses of water per day, otherwise he'll have health problems earlier in life than is naturally expected. That's 48 oz, or two ounces less than a Double Gulp from 7-11. Not an unmanageable amount of water, but think about how often you only had two or three glasses of water during days where soda, coffee, beer and wine made up the rest of your fluids.
Now imagine you weigh 300 pounds. You have roughly double the amount of cells as a healthy person. And all those cells need hydration and nourishment. Are you drinking 100 oz. of water each day? You better be! Because there are only so many times your cells can die and replace themselves with perfect copies, without their basic needs being met.
For a well hydrated person, you are looking at about 80 - 85 years before you start getting cancer and heart-attacks naturally. When I say naturally, I mean, the DNA in your cells have these things called telomeres. Think of telomeres as the little plastic tips on the end of your shoelaces (http://en.wikipedia.org/wiki/Aglet) which keep them from fraying.
Whenever a normal, undamaged cell in your body dies of natural causes (roughly once every seven years), the cell reproduces itself, The young cell is a copy, and then -- seven years later -- a copy of a copy. Every time it reproduces, it is exactly the same except the telomere is shorter. Once it starts to fray like a shoe-lace, you get liver-spots, skin-tags, heart-attacks, cancer... all sorts of originally unintended things.
If cells don't get the stuff they need -- oxygen, water and nutrients (nutrients are another thing the obese simply can't get enough of -- we are literally starving our cells. By taking in too many protiens and sugars (which generate new cells) and not enough energy-sustaining phyto-nutrients (which keeps existing cells healthy) it's creating starvation, at the cellular level.
Not unlike a fallen empire of history -- if your organs' infrastructural constituents are not strong and sustained over a long period of time, the entire thing crumbles from the inside out.
So lets say all our cells can reproduce about twelve times, before the noise of nature overcomes their structure. That's 84 years.
Now let's say that your cells are getting half of what they need, due to the ratio shift that obesity brings to cellular resource requirement -- and we'll grant the 26 year buffer during which all lifestyle damage is virtually reversible due to our Wolverine-like regenerative capabilities of young. That's 68 years of life, based on an initially generous 84 years of natural life...
There's a reason there aren't many bariatric geriatrics, and that's because a chronically obese human enters their "naturally" geriatric period much younger.
This is not to say that we chronic 300-pounders (which this author is one) can necessarily compensate for our extra cells by simply knocking back two double-gulps per day. We don't know that the kidneys can re-insert enough of that fluid back into the blood stream for that sustained a period of time -- especially without being artificially aged in their own right.
Best thing to do... well... you don't want to hear it, and neither do I.
As a married man living in the United States circa 2015, I couldn't possibly ask for for a better life, and I couldn't readily deserve a life half this good. There remain strands of that old psychic tether to the ludicrous superstition that most people eventually get what they deserve. When the relentlessly high quality of my life begins to elicit fits of bitter paranoia, it's clearly time to begin giving something back to the world which has been so nurturing and gratifying that virtually all of my life's suffering has emanated from within.
"It was astonishing how loudly one laughed at tales of gruesome things, of war's brutality -- I, with the rest of them. I think at the bottom of it was a sense of the ironical contrast between the normal ways of civilian life, and this hark back to the caveman code. It made all of our old philosophy of life monstrously ridiculous. It played the hat trick with the gentility of modern manners -- men who had been brought up to christian virtues, who had prattled their little prayers at their mothers' knees, who had grown up to love poetry, painting, music, the gentle arts, over-sensitized to the subtleties of half-tones, delicate scales of emotion, fastidious in their sense of words, in their sense of beauty, found themselves compelled to live and act like ape-men. And it was abominably funny. They laughed at the most frightful episodes, which revealed this contrast between civilized ethics and the old beast law, the more revolting it was, the more sometimes they shouted with laughter, especially in reminiscence, when the tale was told at the gilded salon of the french chateau, or at the mess table. It was the laughter of mortals at the trick which had been played on them by an ironical fate. They had been taught to believe that the whole object of life was to reach out to beauty and love. And that mankind in its progress to perfection had killed the beast instinct: cruelty, blood-lust, the primitive, savage laws of survival by tooth and claw and club and axe. All poetry, all art, all religion had preached this gospel and this promise. Now that ideal had broken like a china vase, dashed to hard ground. The contrast between that and this was devastating." -Phillip GibbsRecited by Dan Carlin on his podcast Hardcore History. It's a pretty important series in which Carlin illuminates historical engagements for the lay-person, with the approachability of an off-duty professor at the pub. Check out his entire series on World War One, entitled "Blueprint For Armageddon".