Postabsorptive respiratory quotient and food quotient-an analysis in lean and obese men and women

Objective: Macronutrient intake is difficult to measure under free-living conditions, because of errors in the reporting of food intake. The aim of the current study was to assess whether postabsorptive respiratory quotient (RQ) is indicative for the food quotient (FQ), with other factors, such as body composition and energy balance, taken into account. Subjects: Thirty lean subjects (age 31+/-9 y, body mass index (BMI) 22.0+/-2.1 kg/m2) and 20 obese subjects (age 48+/-12 y, BMI 33.3+/-4.4 kg/m2) participated in the study. Design: Body mass changes were determined over a 7 day period before the measurement of postabsorptive RQ and in this period subjects reported their total food intake in a dietary record. A subgroup of 12 lean subjects was supplied with their total food intake in this period (twice with different diets). Food quotients were calculated from the valid food records (<10% underrecording and undereating). Body composition was estimated using the three-compartment model of Siri. Results: Postabsorptive RQ was not related to FQ (n=31, r=-0.24, P=0.2) and no difference was observed between the two diet periods (n=12 paired t-test, P=0.9). Postabsorptive RQ was related to the change in body mass (r=0.57, P=0.0001), but not to BMI, fat mass or fat-free mass. Conclusions: In the present study, the energy balance over the days prior to the measurement was the most important factor influencing postabsorptive RQ. Postabsorptive RQ was not a reliable indicator for habitual FQ even when corrected for energy balance and body composition. European Journal of Clinical Nutrition (2000)54, 546-55

Repeated measurement of habitual food intake increases under-reporting and induces selective under-reporting.

: Br J Nutr 2001 May;85(5):629-34 Related Articles, Books, LinkOut Repeated measurement of habitual food intake increases under-reporting and induces selective under-reporting. Goris AH, Meijer EP, Westerterp KR. Department of Human Biology, Maastricht University, The Netherlands. [email protected]. The aim of the current study was to measure differences in reporting behaviour between a first occasion of 7 d food recording and a second occasion of 7 d food recording 12 weeks later, in a group of elderly men (n 17) and women (n 17). Half the group followed an exercise intervention. The mean age was 61 (sd 5) years and mean BMI was 26.2 (sd 3.8) kg/m2. Reported energy intake was compared with energy expenditure as calculated from measured BMR and physical activity assessed with a tri-axial accelerometer for movement registration. Total under-reporting was divided into undereating and under-recording. Undereating was calculated from the change in body mass over the recording week and the under-recording was measured using the water balance technique. In the first period, the total under-reporting was 21 % and increased to 27% in the second period In the first period there was no indication for subjects eating less during the recording week, however, in the second period subjects lost body mass during the food recording indicating undereating. The amount of under-recording was calculated at 21% in the first period and 18% in the second period of recording (P 0.28). During the second period subjects selectively under-reported their fat intake and over-reported their protein intake. In conclusion, repeated assessment of food intake caused a higher quantitative and a qualitative under-reporting of food intake. The effect of interventions (dietary or otherwise) on habitual food intake might be confounded by changes in food-reporting behaviour

Alcohol energy intake and habitual physical activity in older adults

Alcohol forms a significant component of many diets and it supplements rather than displaces daily energy intake. Surprisingly, alcohol intake does not systematically increase body weight. The present study assessed whether a higher level of habitual physical activity in the daily environment is associated with a higher alcohol intake. Alcohol intake as part of total food intake was measured with a 7 d dietary record while at the same time physical activity was monitored with a tri-axial accelerometer for movement registration. Subjects were twenty women and twenty-four men, aged 61+/-5 years, of BMI 27.1+/-4.6 kg/m(2). Between subjects, there was a positive association between the level of habitual physical activity and alcohol intake (r 0.41; P<0.01). The subjects with higher alcohol intake had a higher activity level. On days with and days without alcohol consumption there was no difference in physical activity within subjects. In conclusion, it was shown that subjects with higher alcohol consumption are habitually more active. This may explain the lack of increasing body weight through additional energy intake from alcohol

Habitual meal frequency in relation to resting and activity-induced energy expenditure in human subjects: the role of fat-free mass

Habitual meal frequency in relation to resting and activity-induced energy expenditure in human subjects: the role of fat-free mass. Westerterp-Plantenga MS, Goris AH, Meijer EP, Westerterp KR. Department of Human Biology, University of Maastricht, Maastricht, The Netherlands. [email protected] Habitual meal frequency was assessed as a possible function of components of energy expenditure (EE) in human subjects. Fifty-six subjects participated (four categories differing in body composition): ten older women (fat-free mass (FFM) 42.0 (sd 6.3) kg, aged 59 (sd 2) years, BMI 27.5 (sd 6.9) kg/m(2)), fifteen younger women (FFM 45.5 (sd 5.2) kg, aged 34 (sd 10) years, BMI 21.9 (sd 2.3) kg/m(2)), twelve older men (FFM 56.8 (sd 5.9) kg, aged 62 (sd 4) years, BMI 25.7 (sd 3.3) kg/m(2)) and nineteen younger men (FFM 63.9 (sd 7.5) kg, aged 23.1 (sd 3.9) years, BMI 22.9 (sd 1.8) kg/m(2)). Measurements consisted of habitual meal frequency by validated food-intake diaries, physical activity by tri-axial accelerometers and resting EE by a ventilated hood system. Habitual meal frequency was expressed as a function of resting EE (including resting EE as a function of FFM), and of activity-induced EE, using regression analysis. FFM differed according to gender and age categories (P<0.01). Physical activity level was higher in the younger men than in the other categories (P<0.05). No relationship of meal frequency with the variables assessed was observed in subjects with a low FFM (the women). In the subjects with a medium FFM (the older men), meal frequency was positively related to resting EE (r(2) 0.4, P<0.05), but not to the residuals of resting EE as a function of FFM, and inversely related to activity-induced EE (r(2) 0.3, P<0.05). Resting EE explained 40 % of the variation in meal frequency; adding activity-induced EE increased this to 60 %. In the subjects with a high FFM (the younger men), meal frequency was inversely related to resting EE (r(2) 0.8, P<0.0001) and to the residuals of resting EE as a function of FFM (P=0.03), and positively related to activity-induced EE (r(2) 0.6, P<0.0001). Resting EE explained 85 % of the variation in meal frequency; adding activity-induced EE increased this to 89 %. Habitual meal frequency was a function of components of EE, namely resting EE and activity-induced EE, only in subjects with a medium to high FFM (men). FFM-related differences in these relationships suggest a role of physical activit

Exercise-induced oxidative stress in older adults as a function of habitual activity level

OBJECTIVES: It has been suggested that regular physical activity might maintain and promote the antioxidant defense capacity against oxidative stress. Therefore, we assessed exercise-induced oxidative stress in relation to habitual physical activity level (PAL) in older adults. DESIGN: The study included a 2-week observation period for the measurement of average daily metabolic rate (ADMR) and PAL. Exercise-induced oxidative stress was measured during a 45-minute cycling test at submaximal intensity. SETTING: A university medical research center. PARTICIPANTS: Twenty-six subjects volunteered for the study (n = 26; mean age ± standard deviation 60 ± 1; body mass index 27 ± 1 kg/m2). MEASUREMENTS: PAL was determined as ADMR combined with a measurement of basal metabolic rate (BMR): PAL = ADMR/BMR. ADMR was measured over 2 weeks with the doubly labeled water method, preceded by a BMR measurement with a ventilated hood. Antipyrine oxidation was used as marker for oxidative stress in vivo. Reaction of antipyrine with hydroxyl radicals results in the formation of para-hydroxyantipyrine (p-APOH) and ortho-hydroxyantipyrine (o-APOH), where o-APOH is not formed through alternative oxygenetic pathways. RESULTS: PAL was inversely related to the exercise-induced increase in the ratio of o-APOH to native antipyrine (r = -0.49, P = .010). The relationship between PAL and exercise-induced increase in the ratio of p-APOH (r = -0.30, P = .140) or thiobarbituric acid reactive species (r = -0.31, P = .130) did not reach the level of significance. CONCLUSION: Physically active older adults have a reduced exercise-induced oxidative stress than older adults with a lower level of physical activity. It seems that regular physical activity improves the antioxidant defense capacity

Predicting daily physical activity in a lifestyle intervention program

The growing number of people adopting a sedentary lifestyle these days creates a serious need for effective physical activity promotion programs. Often, these programs monitor activity, provide feedback about activity and offer coaching to increase activity. Some programs rely on a human coach who creates an activity goal that is tailored to the characteristics of a participant. Throughout the program, the coach motivates the participant to reach his personal goal or adapt the goal, if needed. Both the timing and the content of the coaching are important for the coaching. Insights on the near future state on, for instance, behaviour and motivation of a participant can be helpful to realize an effective proactive coaching style that is personalized in terms of timing and content. As a first step towards providing these insights to a coach, this chapter discusses results of a study on predicting daily physical activity level (PAL) data from past data of participants in a lifestyle intervention program. A mobile body-worn activity monitor with a built-in triaxial accelerometer was used to record PAL data of a participant for a period of 13 weeks. Predicting future PAL data for all days in a given period was done by employing autoregressive integrated moving average (ARIMA) models on the PAL data from days in the period before. By using a newly proposed categorized-ARIMA (CARIMA) prediction method, we achieved a large reduction in computation time without a significant loss in prediction accuracy in comparison with traditional ARIMA models. In CARIMA, PAL data are categorized as stationary, trend or seasonal data by assessing their autocorrelation functions. Then, an ARIMA model that is most appropriate to these three categories is automatically selected based on an objective penalty function criterion. The results show that our CARIMA method performs well in terms of PAL prediction accuracy (~9% mean absolute percentage error), model parsimony and robustness

Underreporting of habitual food intake is explained by undereating in highly motivated lean women.

Underreporting of habitual food intake can be explained by underrecording and/or undereating. This study was designed to discriminate between the two errors mentioned, by measuring energy and water balance. Twenty-four lean female dieticians were recruited as subjects. Energy intake and water intake were measured for 1 wk with a weighed dietary record. Energy expenditure was estimated from measurements of resting metabolic rate, and measured physical activity with a triaxial accelerometer for movement registration. Water loss was estimated with deuterium-labeled water. Energy balance was determined by measuring the change in body mass over a nonrecording week (preceding the recording week) and over the recording week. Mean energy and water intake were 8.5 +/- 1.0 MJ/d and 2.3 +/- 0.5 L/d. The change in body mass in the nonrecording week was 0.1 +/- 0.6 kg and in the recording week -0.6 +/- 0.8 kg (paired t test; P = 0.02), indicating 16% undereating. Recorded water intake plus calculated metabolic water closely matched measured water loss (r = 0.93; P = 0.0001), which indicated a high recording precision. In conclusion, in the studied group of highly motivated lean women, there was 16% underreporting of habitual food intake, which could be explained by undereating

Improved reporting of habitual food intake after confrontation with earlier results on food reporting

The aim of the present study was to improve the reporting of food intake by confronting subjects with their way of reporting food intake, e.g. under-recording and/or under-eating. To minimize portion size errors, eighteen female dietitians were recruited as subjects. Energy- and water intake were measured for 1 week with a weighed dietary record. Resting metabolic rate was measured with an open-circuit ventilated-hood indirect calorimeter, and physical activity was measured with an accelerometer for movement registration. Water loss was estimated with 2H-labelled water. Energy balance was checked for by measuring empty body-weight 1 week before the start, at the start and at the end of the recording week. In the first part of the study, the change in body weight in the non-recording week was 0.14 kg and in the recording week -0.45 kg (P 0.02), indicating 12% under-eating. Total water intake closely matched measured water loss, indicating a high recording precision. There was under-reporting of habitual food intake that could be fully explained by under-eating. In the second part of the study, subjects were confronted with these results and the protocol was repeated. This time there was no significant change in body weight in the recording week, indicating no under-eating. The reporting of habitual food intake had been improved. In conclusion, in the studied group of highly motivated lean women, under-reporting of habitual food intake (here due to under-eating) could be eliminated by confrontation with the results of this phenomenon

Validity of the assessment of dietary intake: problems of misreporting.

Department of Human Biology, Maastricht University, Maastricht, The Netherlands. [email protected] PURPOSE OF REVIEW: This is a review of recent studies on the analysis of misreporting of food intake and on the consequences of misreporting for the interpretation of dietary surveys. Bias in the assessment of dietary intake was analysed from studies comparing reported intake with doubly labelled water assessed energy expenditure. RECENT FINDINGS: There is not yet a method for the accurate determination of dietary intake. Physical and psychological characteristics of study participants play an important role in the observed reporting bias. The degree of misreporting might increase with repeated dietary assessment in the same subjects, confounding the results of intervention studies. SUMMARY: Campaigns aimed at changing food intake might not be as successful as concluded from the results of national food consumption measurements. Subjects might be reporting according to expected instead of real intake. In a clinical setting, the increased awareness of the nursing staff has been observed to result in overreporting of intake. Publication Types: Review Review, Tutoria