How to lose weight and keep it off
As Americans and others on Western diets continue to suffer from a weight epidemic, they continue to be told to eat less and get more exercise, and they continue to diet but then regain the weight they lose. Unfortunately, recent research suggests this will only continue.
For example, a recent study showed that dieters still feel hungry and obsess over food for long periods of time after losing a significant amount of weight from dieting. Hormones in the blood that help keep appetite in check were still significantly lower than before the weight loss a year after completing the diet.  The researchers suggest that, until the problem of reduced hunger reducing hormones is addressed, dieters will continue diet and relapse. Although some research has already been completed on the hunger hormone leptin, the results were “variable”. 
For most of human evolution, maintaining body fat actually played a major role in helping us survive and our bodies are apparently unwilling to let us give it up without a fight.  If we go without food or with a reduced level of food for even twelve hours, our brains will try to focus all our attention on getting more food. This focus on eating undoubtedly got our ancestors through numerous famines by storing up fat during good times. Unfortunately, we’re apparently having too many good times. Our fat stores an amazing amount of energy – which means we have to go hungry for quite a while in order to lose the pounds. One person underwent a therapeutic fast for over a year to reach a healthy weight. 
Food addiction is now receiving consideration as a real phenomenon, and that pharmacological and behavioral interventions similar to those used for drug addictions are needed. Take, for example, sugar-bingeing rats. Rats provided with a sugar and fat solution for just two hours per day consumed the majority of their calories from this solution even though regular mice chow was continuously available. Like opium smokers, they increased their consumption over time during the two hour window and then again after a period when the solution was no longer available daily. 
Drinks containing high fructose corn syrup are no longer just considered simply empty calories. Some now consider fructose to be a chronic liver toxin, much as alcohol is. Fructose continues to be strongly implicated in studies for causing cardiovascular disease, type two diabetes, and cancer, and for making our abdomens fat (which is considered a marker for cardiovascular disease). And since table sugar, sucrose, is half fructose, it is similarly implicated. ,, Unfortunately, most Americans seem totally unaware of this. One of the more vocal fructose critics is Robert Lustig, a Professor of Pediatrics at the University of California at San Francisco. A video of his 1.5 hour lecture, “Sugar: The Bitter Truth” garnered a lot of attention since it was released in 2009. If you haven’t seen the Lustig video, I recommend it if you have the time:
And perhaps fructose is making us more at risk for depression. Evidence is mounting that inflammation plays a role in depression, and adipose tissue in the abdomen (belly fat) is a primary source of inflammatory factors associated with depression. If body fat can cause depression and depression can cause body fat, there is the possibility of a viscous cycle. , 
On a more positive note, a large study was published in 2011 by the New England Journal of Medicine which examined the effect of diet and lifestyle on weight gain in non-obese individuals. The foods most associated with weight gain were not surprising: french fried potatos, potato chips, potatoes, sugar-sweetened drinks, processed and unprocessed red meats. French fries were by far the worst food and anyone who loves deep fat fried foods should take notice. Foods that were associated with weight loss were yogurt, nuts, fruits, whole grains and vegetables. Why yogurt consumption is associated with weight loss is unknown. It’s possible that gut bacteria influence weight gain or maybe yogurt consumers just tend to have more healthy behaviors. 
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So, what to do?
Until there are interventions for hunger hormones and food addiction, we will have to make use of the tools and knowledge we have now:
Stop consuming sugared drinks, including sodas, chocolate milk and fruit juices, starting now. Fructose in its natural form- fruits and vegetables- is fine. The fiber in these foods slow down the digestion of the fructose and it is processed via burning instead of storage. When you see a sugar drink, think “chronic liver toxin”.
See your doctor about the possibility of a therapeutic fast. Your doctor will probably suggest a restricted calorie diet instead as this is much safer. Fasting can be dangerous without regular blood tests to see what’s happening in your system, so don’t go it alone.
Exercising has long been known for playing a central role in controlling appetite. Exercise also detoxifies fructose by burning it instead of storing it as fat, and increases your metabolism, among other things. The average participant in the National Weight Control Registry (a data base of people who have maintained at least a 30 pound weight loss for one year or longer) burns around 2,600 kcal/week exercising.  For a 200 pound person, this is equivalent to one hour and fifteen minutes of walking at 3 mph per day. Even if you can’t adhere to a diet, and even if it doesn’t seem to help shed any pounds, you should still exercise.
Find a dieting plan or plans that you can stick with over a long period of time even though your body is attempting to undermine you at every turn. The safest bet is probably the paleolithic diet since humans evolved eating this diet over hundreds of thousands of years. (See the related link below for an example.) It includes no grains, milk products or refined sugar.
The type of diet you choose is not as important as your adherence to it.  You will feel hungry and constantly prompted to eat over an extended period of time (perhaps years) even after reaching your target weight, so put some serious thought into how you are going to deal with hunger.
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Don’t try to be a perfectionist. Occasionally you are going to eat something you shouldn’t because it’s too tempting. Attempting to be a perfectionist makes an extremely difficult task next to impossible, so don’t go to tears if you sneak a donut once in a while.
Finally, set a weight goal that is specific and difficult to achieve. The harder the goal, the higher the performance. Specific goals (135 pounds by January 1) are better than vague goals (lose some belly fat) because vague goals are always met even if you don’t even try.
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