Recently, the Department of Health and Human Services launched their first Physical Activity Guidelines for Americans . This was in direct response to the national obesity epidemic whose effects can be seen everywhere. The U.S. Centers for Disease Control have stated that adult obesity rates doubled since 1980, from 15 percent to 30 percent while childhood obesity has almost tripled during the same time period, from 6.5 percent to 16.3 percent.

While it is great that these new guidelines are here, it is fair to ask why it took so long for them to be published. The answer to that is clear. The responsibility for carrying out physical activity is almost entirely in the hands of individuals. If individuals don't make the effort to do physical exercise, then there is no one to blame but themselves. This is, of course, much more related to adults than children. For children, it is both the home and school environment that is largely responsible for the amount of exercise they do.

Because of the great degree of personal responsibility associated with physical exercise, there has been little attention paid to this issue on the part of consumer advocacy groups, whose political capital is largely the result of finding businesses and large institutions to blame for problems. With reference to the obesity epidemic, consumer advocacy groups invariably blame the food industry for producing high fat, empty calorie foods, and, to a lesser extent, they blame the government for not regulating the industry. It is a very rare occurrence when a consumer advocacy group calls on consumers to bear their share of the responsibility for managing their lifestyle and matching their food consumption with energy expenditure through physical activity.

Thus, while the Physical Activity Guidelines for Americans has just been published, the Dietary Guidelines for Americans is in the process of preparation of its sixth iteration since 1980.

It is strange that it is only since the first iteration of the Dietary Guidelines for Americans that we have experienced the obesity epidemic. This does not say much about the effectiveness of the Dietary Guidelines and the people or institutions that have developed them. Considering what has happened to our physical condition in the last quarter century, one wonders if Americans would have been better off without the Dietary Guidelines. Is it possible that this could have been corrected if the Physical Activity Guidelines were issued at the same time? Not likely.

As much as the Department of Health and Human Services (HHS) and the Department of Agriculture (USDA) assure us that the Dietary Guidelines are evidence-based, they are about the worst example of this that anyone might choose. The Dietary Guidelines are predominantly based upon opinion - the absolutely lowest level of evidence in the hierarchy of acceptable evidence. In fact, some of the evidence upon which the Guidelines are based is so subjective, there have been complaints that certain of the Guidelines should never have been issued. Unfortunately, there are certain segments of our society that have an burning desire to provide guidance, no matter how ill-advised.

If you consider both the Dietary and Physical Activity Guidelines, you will see that they don't really relate to one another. (It is interesting to note that the Physical Activity Guidelines are issued by the HHS alone, while the Dietary Guidelines are issued jointly by HHS and USDA - are there some issues at play here?) While food products carry labels that indicate the energy content (calories) of each serving, it is almost impossible for consumers to easily translate this into the amount of physical activity required to expend the energy taken. People who watch their weight and exercise regularly are an exception. They have a good idea of what extra energy will have to be burned off in order to make up for extra food consumption. If they treat themselves to a few extra chocolate chip cookies, then they put in the effort to jog for an extra half hour in order to burn the calories off.

Instead of putting calories on the food label, why don't they put the physical activity equivalent on, so that people will have an idea of what they have to do to get rid of that additional intake. That is the sort of thing that will link the Dietary and Physical Activity Guidelines together - calories by themselves simply don't convey the energy input/output message to consumers.

Getting consumers to relate their diet to physical activity and energy expenditure is not rocket science. It does, however, require a sensitivity to the needs and awareness of consumers rather than a focus on political expediency and a compulsion to give advice by a medical establishment that has still to learn what food and nutrition are all about.