Food Habits Survey

MRC EWL’s role for the NDNS RP

National Health and Nutrition Examination Survey
Conclusions A questionnaire, derived in part from one previously published to assess physician knowledge, can be used to determine medical student awareness of nutritional facts. Guidelines on macronutrient recommendations We see the question of what to teach as the most critical problem in introducing or expanding nutrition education in the medical school course. Four of the 14 questions presented to the first year medical class were included in a recent survey of physicians published in this journal [ 4 ]. In addition to the effect on risk factors, epidemiologic evidence suggests that replacing fat with carbohydrate is deleterious. New York, Oxford University Press; Some of the major problems frequently cited are 1 inflexibility in the curriculum due primarily to time constraints and 2 inability to define what aspects of the subject needs to be taught. Take this quiz to gain some insight on why you smoke.

Background

Nutrition Questionnaire

Questionnaires were collected from students, all but 6 of whom answered all the questions. Because the questions had different goals knowledge assessment vs. Results from the first eight questions and the data from Flynn, et al.

Discrimination coefficients indicate discrimination of high and low performers on quiz overall as described in the text. First year students did not do as well as physicians at identifying sources of monounsaturated fats. On the other hand, the good discrimination coefficient indicates that knowledge of fat composition is a good indicator of overall knowledge at least as assessed by general performance on this quiz. Likewise, a very small fraction of first year students or physicians were aware of the association between low fat diets and two markers of CVD, triglycerides and HDL-c.

Student responses attest to the success of continued popular and government recommendations favoring low fat diets but the content of the answers raises the question of whether sufficient information is being disseminated.

It further raises the question as to whether these recommendations, rather than the basic nutritional knowledge, should be communicated.

Along the same lines, our questionnaire went beyond the area covered by Flynn to consider the changes in diet that have accompanied the epidemic of obesity. The observation of a decrease in fat and an increase in carbohydrate in parallel with the obesity epidemic remains as a serious challenge to traditional dietary recommendations.

Although more difficult to quantify, a decline in exercise is also a likely contributor to the epidemic, but it seems inappropriate, without further evidence, to ignore the prima facie evidence of the effect of macronutrients. Despite the clear correlation between higher carbohydrate, lower fat and obesity, government and health agencies rarely question the appropriateness of the original guidelines and have continued to recommend still higher carbohydrate and still lower fat [ 6 , 30 , 31 ].

Such recommendations have to be considered controversial and likely to change. For this reason we feel that one of the points brought out by our quiz and Flynn's is that nutritional facts rather than official recommendations should be the goal of nutrition education.

Changes in fat and carbohydrate between and Data from USDA as reported in reference [24]. We were surprised by some lapses in student knowledge revealed by the questionnaire. The National Board of Medical Examiners assumes knowledge of caloric value of macronutrients, and we had expected that it was common knowledge. The questionnaire result indicates that no fact in nutrition is too basic to be excluded from course material.

An overwhelming number of medical students believe that diet is as effective as drugs in lowering total cholesterol. This again attests to the pervasive message that diets control blood cholesterol, an idea continually reinforced by media advertisements, for example, for the cholesterol lowering effect of breakfast cereal.

Whereas it is likely that diet is an important influence on CVD, there is, again, the problem of which diet and the question would probably have been better framed, as in questions 2—4, on specific lipid components. It is likely, for example, that many medical students would not know that dietary cholesterol is largely without effect on serum cholesterol. In any case, it is generally acknowledged that, on average, drugs such as statins have a greater impact on cholesterol than currently reported diet interventions.

The general effectiveness of statins and the promotion by pharmaceutical companies has, most recently, led to a movement to reinforce the idea that genetics which can't be controlled by diet also plays a role. The competing financial interests have produced, in our view, bizarre and unpatriotic? Few students in the first year medical class knew that replacing unsaturated fat with carbohydrate was the most damaging substitution in terms of an association with CVD risk. The data from Hu, et al.

Similar results have been found in the analysis of risk factors [ 14 ]. In other words, whereas everybody agrees that removing fat from the diet as a mechanism of calorie reduction is a good thing, replacing fat with carbohydrate correlates with an increase in CVD risk and is likely worse for weight loss. Data from Hu, et al. The glycemic index GI , and the glycemic load GL which corrects for total carbohydrate in individual foods, are indicators of rise in blood glucose.

Glycemic control is a major variable in the analysis of metabolic syndrome and obesity, and dietary strategies based on the glycemic index [ 28 ] have the same rationale as low carbohydrate diets: A low carbohydrate diet might be described as a very low glycemic load diet.

Nonetheless, the concepts of GI and GL have become part of the political controversies surrounding dietary strategies and proponents usually urge a low GI diet as an alternative rather than a variation of low carbohydrate diets [ 15 ] despite the fact that in at least one isocaloric comparison of high GI and low GI meals, the low GI meal was, in fact, lower in carbohydrate [ 27 ].

An important limitation on the concept of GI is that fructose and therefore fructose-containing products such as sucrose and high-fructose corn syrup may have low values, although these substances may not be desirable.

The atherogenic qualities of fructose [ 32 ] is one of the ideas that we bring out in the lectures in the medical school course. We recommend that the term complex carbohydrates not be used since, in practice, it has lost its original meaning of polysaccharide. It is interesting that, to some extent, student answers followed the original definition.

Most students picked both white bread and whole wheat bred as complex although, with a slight preference for picking whole wheat over white bread as many health professionals and the lay public might.

In our view, however, this may be a mixed blessing because it shifts the emphasis from macronutrient composition, a major factor in health, to micronutrients, which, at least for the American population, has to be considered secondary. The relatively low performance and good discrimination coefficient in the question on redox precursors is somewhat discouraging, especially in that students had been exposed to the involvement of the three oxidative coenzymes in glycolysis and the TCA cycle.

Moreover, the origin of NAD coenzymes in dietary niacin was explicitly taught. We think this apparent deficiency likely results from a lack of emphasis on integration of nutritional information with biochemistry. We identify folate metabolism as one of the critical areas of biochemical nutrition. The importance of homocysteine and use of dihydrofolate reductase inhibitors such as methotrexate are two of the most obvious examples of how biochemistry is a practical part of medicine.

At the same time, the biochemical pathways are among the most complex, and because folate spans different areas of metabolism, it is difficult to teach. The key nutritional issues are covered both in lecture and in a case-based learning session. Many papers have been written on the need for, and the difficulty in implementing, improvements in teaching nutrition in medical schools [ 2 , 3 , 33 ]. Some of the major problems frequently cited are 1 inflexibility in the curriculum due primarily to time constraints and 2 inability to define what aspects of the subject needs to be taught.

There is also considerable disagreement on the best method of teaching the subject. The current study bears on some of these questions. With respect to point 1 above, the first year medical school curriculum is undoubtedly very dense in content. Adding new material is difficult, especially if it is of the strictly factual type, e. The "low pressure" quiz used here can, in theory, impart a certain amount of specific knowledge and generate student interest without interrupting the general flow of course work.

The quiz provides a venue in which interested students can absorb the information, and become aware of the general area if they need to find the information later. Also, in our view, many subjects taught in basic science courses already have nutritional relevance, e.

We point out, when the NAD cofactors are introduced, that one would expect global effects of a deficiency disease because of the number of different enzymes that use these cofactors. Although vitamin deficiencies are rare in the absence of gross malnutrition, the emerging role of hypervitamin therapies [ 34 ] has great pedagogical value.

The tie-in through the quiz may reinforce the basic biochemistry. We see the question of what to teach as the most critical problem in introducing or expanding nutrition education in the medical school course. Individual faculty may be resistant to giving up their own interests, but this may depend on how well the case is made for changing to new topics. The original study by Flynn was designed to test physicians' knowledge and expand it to allow them to better implement ATP III recommendations on serum triglycerides.

In combination with other questions that we have introduced, the general problem arises as to whether these recommendations or nutritional data should be taught. Given that low fat diets tend to raise triglycerides, the associated recommendations to reduce dietary fat and to raise carbohydrate intake appear somewhat contradictory. Thus, whereas the association between cholesterol levels and CVD is generally accepted by all but a minority of critics, the effect of diet, especially reduced fat diets, on CVD, or even cholesterol, is far more controversial.

The Chapter on "Diet and Coronary Heart Disease CHD " in Willett's Nutritional Epidemiology [ 35 ] is 40 pages long with more than references and contains more than one disclaimer on the diet-heart hypothesis, e. A viewpoint strongly against [ 37 ]" These cautionary reports as well as those of other critics of low fat dietary recommendations [ 8 , 19 , 38 - 40 ] are largely ignored by the ATP III and the body of experts who are making current recommendations.

The recent demonstration of a beneficial effect of saturated fat and lower carbohydrate in patients on an overall low fat diet [ 41 ] has been described in an accompanying editorial as an "American paradox. The extent to which researchers seek to resolve this paradox remains to be seen. The analysis above also bears on the role of low carbohydrate diets in educating students and physicians.

We have previously indicated how such diets can be used to teach basic intermediary metabolism [ 43 ] and whereas we do not recommend any particular diet, we feel that the biochemical rationale of carbohydrate restriction makes it increasingly difficult to justify exclusive recommendations for low fat, high carbohydrate guidelines. In summary, what to teach remains very problematic.

This has to make one question whether students and physicians should be educated only in currently recommended practice, or whether we should instead emphasize understanding the underlying data.

This is especially true, given the disclaimers in the American Heart statement [ 31 ] that "These recommendations may require modification, based on the results of ongoing and future dietary therapy studies. The resolution currently depends on individual instructors and departments. It would be good pedagogically to establish the idea that not everything is known about nutrition and that many people consider that a rush to guidelines on insufficient evidence is to be avoided. A questionnaire, derived in part from one previously published to assess physician knowledge, can be used to determine medical student awareness of nutritional facts.

At the same time, such a quiz can be employed as a teaching device to reinforce earlier material, provide preview of new material, or expose students to factual information that is not easily incorporated into a formal course. One of the areas chosen, the effect of macronutrients on obesity and cardiovascular disease, can lead to discussion and focus on important current issues.

The performance of first year medical students as well as the performance of the physicians in the previous study suggest that improvement is needed in imparting knowledge about some basic ideas in nutrition.

We believe that the focus should be on these ideas rather than on official recommendations with which the ideas are sometimes in conflict. Finally, the questionnaire is intended as a practical method. Several people have provided valuable help and suggestions.

The authors thank Dr. John Kral of the Department of Surgery and Dr. National Center for Biotechnology Information , U. Journal List Nutr J v. Published online Jan Mary Makowske 1 and Richard D Feinman 1.

Mary Makowske 1 Department of Biochemistry. Richard D Feinman 1 Department of Biochemistry. Received Nov 28; Accepted Jan This article has been cited by other articles in PMC. Abstract It is generally recognized that there is a need for improved teaching of nutrition in medical schools and for increased education of the general population.

Methods The following is a verbatim reproduction with addition of references of the questionnaire given to first year medical students at SUNY Downstate Medical Center. Questionnaire This questionnaire is anonymous and does not affect your grade.

A good source of monounsaturated fat is: In general, what effect does a low-fat diet have on triglycerides? In the past thirty years, the per cent fat in the American Diet has: High total blood cholesterol can be lowered significantly by: The dietary change that is most likely to increase the risk of cardiovascular disease: MRC EWL inputs include logistics support and fieldworker training for sample collection, laboratory analyses, results analysis, and interpretation and reporting.

These resulted in separate reports on sodium intakes for adults aged 19 to 64 years in England , Scotland and Northern Ireland published in What do UK children and adults eat? The NDNS interview collects data on Demographic and socio-economic characteristics Dietary habits, food and nutrient intake and population trends in food consumption Physical activity Oral health General health and lifestyle, including smoking and alcohol consumption A spot urine sample for iodine status assessment Food intake data is collected using an estimated unweighed 4-day food diary.

The nurse visit includes: Dietary assessment Fieldwork support and training and logistics support Blood and urine specimen logistics and analysis Management of the NDNS Biorepository Doubly-labelled-water logistics and analysis Data management Statistical analysis and reporting The success of the NDNS RP depends on the good will and voluntary cooperation of members of the public across the UK.

Findings from the Eating environment and meal satisfaction study Study purpose The environment in which food is eaten may affect how This information provides a general overview and may not apply to everyone. Talk to your family doctor to find out if this information applies to you and to get more information on this subject.

Two of the simplest yet most important ways to have a healthy heart are through diet and exercise. Take this quiz to gain some insight on why you smoke. Then, use that information to help you quit. Visit The Symptom Checker. Tips for Healthy Children and Families. What You Should Know.

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