Simple carbs spike up blood sugar through the roof, the body responds by dumping insulin, the insulin causes blood sugar to be sequestered in fat and muscle cells (as intended), but if the dump is large it may overshoot and the blood sugar falls through the floor. Aka "sugar crash". The crash will of course make you crave food again, the same simple carb kind. Vicious cycle.
This sort of see-saw messes you up real bad. So I was told 
I have since then thrown in intermittent fasting as well. I fast 22 hours a day, work out at the end of the day, and then go home and eat 1kg of steak/lamb. I think intermittent fasting is worth adding to any diet, vegan or otherwise.
 Book was printed in 1956, so copyright may have expired. There's PDFs online. Here's a link to Stefansson's Wikipedia entry: https://en.wikipedia.org/wiki/Vilhjalmur_Stefansson
 Non-affiliate: https://www.amazon.com/Why-We-Get-Fat-About/dp/0307474259
then, as others have said, reddit.com/r/keto is good for "how to"
I read that 4 years ago, spent another 4 months reading the listed studies, convinced myself it was a good plan, and lost 40 pounds with no exercises. I still do LCHF after all these years, and likely will never go back to a traditional diet, it feels great.
In short, for most of us, our fat tissue is regulated primarily through our response to insulin.
The third chapter is all about why exercise isn't a good way to lose weight. It is generally a fantastic book.
When I first encountered the idea that we do not get fat from eating too much and that calories weren't responsible, I thought it ludicrous—the body can't disobey the laws of physics! Thermodynamics! But after seriously thinking about the idea, I realized Taubes was providing a far more complete understanding of metabolism. The human body doesn't run on calories, it runs on food. Yes, we can easily learn the caloric content of food, but that's largely irrelevant. What's important is how food affects the body, not its raw energy content. I see this misconception time and time again, especially among smart people who like to reduce the human body to merely a physical machine, often ignoring the whole biology thing.
I think the hormone theory of obesity is correct and I think these studies will prove it. But even if they show otherwise, this type of research is long overdue and we all stand to benefit from the results.
Why We Get Fat: And What to Do About It
Good Calories, Bad Calories: Fats, Carbs, and the Controversial Science of Diet and Health
From things I've read  it seems that the vast majority of people consume more calories than they 'burn' but only in some people is it converted to unwanted weight gain. The real question, as many people have been referring to, is how do you determine whether your body hangs onto the extra calories as weight or simply disposes of it.
Saying "If you eat less energy than you burn, you will lose weight" is certainly true, but is akin to saying: "If you never get in a car your chances of dying in a car accident are significantly reduced." It's true...but not really helpful or meaningful.
1 - http://www.amazon.com/Why-We-Get-Fat-About/dp/0307474259
which is a more accessible version of his more rigorous book Good Calories, Bad calories.
I've been on a bit of a health binge since the beginning of the year and have been doing lots of research into these things. In a nutshell, not all calories are the same the some can wreak havoc on your system (grains, it turns out, aren't that good for us). The Paleo Solution, by Robb Wolf, is another great book - he goes to great lengths to discuss the science and biochemistry behind the points he is making. Highly recommend.
I don't disagree with this, but sometimes motivation is more enabled by a society or cultural milieu and sometimes it's less enabled. In our society, the default is towards simple sugars in everything from ubiquitous soda to donuts in the break room to sandwiches to white rice in restaurants to high-fructose corn syrup in damn near everything. The larger the cultural inertia, the harder the change. Ask vegetarians: in the U.S., meat-eating is the assumed default. I've read that, in India, vegetarian food at events, parties, and so forth is basically the norm.
They can tell us when we need to lose weight and perhaps even give us a general idea of what we need to do, but they really aren't trained to focus on habits and motivation
It's actually more pernicious than that. As described by Taubes in Why We Get Fat (http://www.amazon.com/Why-We-Get-Fat-About/dp/0307272702?ie=...), the government and doctors have spent the last 40 years convincing everyone that a high-carbohydrate, low-fat diet is optimal, and government agencies and many researchers have ignored evidence to the contrary. I don't think this reflects malice on the part of individual doctors, but it does reflect systematic misinformation about what effective nutrition actually is. So doctors haven't only not given "us a general idea of what we need to do," but they've actually told us the opposite, even unwittingly.
The point is that protein and fat satisfy hunger in a way that our bodies have evolved to process. And the fact is, after eating a bit of protein and fat, you won't DESIRE to eat any more.
Seriously, read this book, it will change your life. http://www.amazon.ca/Why-We-Get-Fat-About/dp/0307272702
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