The results from a new government survey into Americans’ eating habits are in and they are a mixture of good and bad. The good news is that the study found Americans do well in getting enough protein, carbohydrates and such key nutrients as selenium, niacin, riboflavin, thiamin, iron, folate, copper and phosphorus. Good news, that is, if you believe the findings.
The U.S. Department of Agriculture (USDA) report is drawn from the ongoing National Health and Nutrition Examination Survey (NHANES), which is conducted by the National Center for Health Statistics. This latest picture of the nation’s eating habits comes from information collected from nearly 9,000 people, aged at least 1 year, in 2001 to 2002, by the Agricultural Research Service in Beltsville.
So can we believe it? The survey method suffers from several weaknesses common to virtually all surveys. This one employs a technque requiring a 24-hour recall. This means respondents are asked to describe exactlly what they consumed during the previous 24-hour period.
Such recalls do suffer from errors. Some people simply forget, no matter how hard they try to remember. Others make a report they think will make themselves look good, so they over state the nutritional quality of their diet. However, with expert development and a good deal of practice in using it, the questionnaire used with the telephone followup technique added, is probably as good as one could expect and hence the data are probably acceptable indicators of general patterns of consumption.
The next hurdle is the interpretation of the data. This is where I have a little more difficulty. I actually doubt that selenium intake is really good and I do wonder about folate as well. Remember that the standards used by the USDA to make these judgements are their rather pathetic RDAs.
However, the findings about which I have little scepticism are those outlining areas of dietary deficiency. The survey found that 93 percent of Americans don’t get the daily intake of vitamin E recommended by the Institute of Medicine. Just over half fall short on magnesium, 44 percent miss eating enough vitamin A, about a third eat too little vitamin C and 14 percent skimp on foods rich in vitamin B6, which is needed to metabolize the good levels of protein said to be consumed.
This latest report did not measure vitamin D intake, but previous studies have shown that many people also fall short on that nutrient, which is important for strong bones and teeth, muscle function and cardiac rhythm.
Clearly, not everyone can afford the best complete and balanced nutritional formula supplement. However, almost everyone needs it in addition to making various dietary improvements, such as avoiding anti-nutrients (foods which actually consume more nutrients than they provide).
Simply eating certain foods in a 24 hour period says little about what is absorbed and assimilated. It does not give an adequate sample to determine the existing nutritional status, food allergies and sensitivities, other nutrient blocking or demanding pathologies, individual differences, nutritional imbalances, and so on. The snapshot provided by the survey actually provides extremely little truely worthwhile data. However, I guess it creates employment so it’s not completely useless.
