I had the great honor to sit down with Dr. Andreas Eenfeldt for a video interview While at the the Metabolic Therapeutics Conference in Tampa last this past February. 
In case you don't already know, Dietdoctor.com is the  largest low-carb site in the world .

We discuss what’s it like to work with low-carb nutrition for patients as an internal medicine doctor.
 We also touch upon what ignited my interest in low-carb nutrition and In what ways can the ketogenic diet be of use to patients.
Find out in our interview, you can watch a segment above where I discuss the need to immediately reduce some medications, like drugs for blood sugar and blood pressure (transcript). The full, longer interview is available on by signing up for membership at dietdcoctor.com: This is something I strongly recommend to all my patients especially when you first start on a low-carb diet.

If you are overweight (or more than overweight),  you got more fat on your body than you want or need. Most people with is problem blame themselves for eating too much and for not going to the gym as much as they think the should. Well guess what? I DON'T BLAME YOU! Accumulating body fat is not caused by gluttony and sloth in fact it is the opposite. The wants of fat cells causes the behaviors of hunger and tiredness.
How come a fat cell wants to grow? It is hormonal. Hormones are chemical signals that circulate in the blood. Insulin, manufactured in the pancreas, is a signal for lots cells types in the body. Importantly, it signals the fat cells to suck in the ingredients of triglyceride (liquid fat) and also not release them. The fat cell, as a result gets bigger. Your belt size and/or behind gets noticeably larger if this process is allowed to continue long enough,  
When insulin is present in super high levels most of the time triglyceride (fat) won't be given the opportunity to escape. It will keep piling up like water behind a dam,  Concentrated, refined carbs are the greatest stimulus of insulin. High concentrations of insulin acts like a high dam on a stream, but not for water, for fat, obstructing its from freely exiting the fat cell.
Imagine a wild undammed stream in a forest, swift narrow and fast moving. Even if it rains more, it gets only a little bigger and only for a little while. Now imagine the same stream after a dam is placed across it. Now it is has a big fat lake in the middle. The lake will remain there even if rainfall remains stable from year to year.
Here is the problem with the calories in calories out model of obesity.  It doesn't account for hormonal regulation of fat cells. I know!! Simplistic and stupid, right?!  Typical calorie counting weight loss methods attempt to achieve weight through less rain to continue with the stream analogy.  They want people to eat less (everything in moderation): add less food to the stream. Even in a drought, the lake of water behind a dam will shrink only a little. So to get rid of your dammed up fat: lower your insulin by cutting out carbs and sugar.