The government recommendations that people receive most of their calories from carbohydrates are almost certainly a major factor in obesity, hyperinsulinism, and diabetes. For some people such a diet is workable, but for many others it is a complete disaster.
Although exercise and a change of diet are certainly helpful, merely trying to eat less isn't the solution. Hyperinsulinism is probably the biggest cause of obesity in this country and is caused not so much by over-eating in general, but rather by excessive carbohydrate consumption. Once insulin resistance and hyperinsulism set in, the result is that insulin still works to convert sugar to fat but is ineffective at converting sugar to energy. The net effect is that blood sugar levels are relatively low (causing sugar cravings) as are perceived "energy" levels, while sugar is converted to fat at an alarming rate.
The remedy is not to eat less, but to go essentially cold turkey on both sugars and starches. Although more and more people are starting to realize the need to minimize carbohydrate consumption, many "diet" programs completely fail in this regard. One can of Slim-Fast® brand ready-to-drink shake, for example, contains 35 grams of sugars--almost double the total daily allowance for the early stages of the Atkins Nutritional Approach™.
Perhaps someday enough people will recognize the perils of carbohydrates that the marketplace will make healthy low-carb foods part of the mainstream rather than an expensive specialty.