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PubMed1989

3H-ouabain binding sites in porcine skeletal muscle as influenced by environmental temperature and energy intake.

The influence of environmental temperature and energy intake on 3H-ouabain binding sites in skeletal muscle has been investigated in young growing pigs at 8 weeks of age. Animals lived for several weeks at 35 or 10 degrees C on a high (H) or low (L) level of energy intake. The four treatment groups were thus: 35H, 35L, 10H and 10L. The total number of 3H-ouabain binding sites (Bmax) in longissimus dorsi muscle (mean values +/- SEM) were 221 +/- 66, 214 +/- 61, 350 +/- 76 and 486 +/- 114 pmol/g wet weight for the 35H, 35L, 10H and 10L groups respectively. Bmax was significantly greater in those living in the cold than the warm (P less than 0.001). Moreover, at 10 degrees C energy intake had a significant effect, with Bmax being greater in the 10L than the 10H group (P less than 0.005). Level of energy intake had no influence on Bmax at 35 degrees C. The apparent dissociation constant was not affected by either temperature or intake. The elevated Bmax and hence the increase in number of Na+,K+-pumping sites in the cold is probably related to increased muscular activity associated with shivering. However, thyroid status also influences the number of Na+,K+-pumping sites and this may have been a contributory factor in the present study. In addition, the elevated Bmax suggests a greater potential for non-shivering thermogenesis associated with increased Na+,K+-ATPase concentration in the cold. Differences in relative stage of development between the four groups may help to explain the results for Bmax in relation to level of energy intake.

Animals↗

PubMed2004

Salad and satiety: energy density and portion size of a first-course salad affect energy intake at lunch.

OBJECTIVE: We tested the effect on meal intake of varying the energy density and portion size of a compulsory first-course salad. DESIGN: The study used a randomized crossover design. SUBJECTS/SETTING: Forty-two women from the State College, PA, university community ate lunch in the laboratory once per week for 7 weeks. INTERVENTION: Lunch comprised one of six first-course salads, or no salad in the control condition, followed by a main course of pasta. Subjects were required to consume the entire salad, but ate as much pasta as they wanted. The salads varied in energy density (0.33, 0.67, or 1.33 kcal/g) and portion size (150 or 300 g). The energy density of the salad was reduced by changing the amount and type of dressing and cheese. MAIN OUTCOME MEASURES: Energy intake and ratings of hunger, satiety, and food characteristics were measured. STATISTICAL ANALYSES PERFORMED: Outcomes were analyzed using a linear mixed model with repeated measures. RESULTS: Compared with having no first course, consuming the low-energy-dense salads reduced meal energy intake (by 7% for the small portion and 12% for the large), and consuming the high-energy-dense salads increased intake (by 8% for the small portion and 17% for the large). When two salads with the same number of calories were compared, meal intake was decreased when the large portion of the lower-energy-dense salad was consumed. CONCLUSIONS: Eating a low-energy-dense first course enhances satiety and reduces meal energy intake. Consuming a large portion of a low-energy-dense food at the start of a meal may be an effective strategy for weight management.

Adult↗

PubMed2003

Energy intake and body composition in anorexia and bulimia nervosa.

Energy intake during the weight gain phase and the weight maintenance phase was examined in three groups of inpatients: 64 anorectic restrictors (AN-R), 37 anorectic bulimics (AN-B), and 74 normal-weight bulimics (BN). The influence of body composition and other variables such as weight, exercise, and bingeing and purging frequencies on energy intake was analyzed. Eating disorder subgroups were found to differ in energy intakes to gain weight and to maintain weight within a target weight range. Anorectic restrictors consumed significantly more energy to gain weight than did the anorectic bulimics (a mean of 3055 kcals per day vs. a mean of 2788 kcal per day). Energy intake for weight gain was inversely related to admission body mass index (BMI) and to admission fat-free mass. Bingeing and purging frequencies did not predict caloric intake for either weight gain or maintenance for anorectics. Energy intake of the anorectic patients when they were maintaining weight within a target weight range did not differ between restrictors and anorectic bulimics (means of 2204 and 2134 kcal/day, respectively). Energy needed to maintain weight within a target weight range was predicted by the amount of fat-free mass at target weight and by the mean number of calories ingested per week during weight gain. Bulimics consumed fewer calories than either of the two anorectic groups during the weight maintenance phase (1538 kcal/day). Other than BMI at hospital admission, bulimics' energy intakes were unrelated to all demographic and eating disorder-related variables, including body composition.

Adipose Tissue↗

PubMed2004

Adjusting for energy intake--what measure to use in nutritional epidemiological studies?

BACKGROUND: The measurement of energy intake in epidemiological studies is difficult. However, it is important that energy intake is assessed if epidemiological analyses are to correspond to isocaloric experiments. The aim of this study was to compare self-reported energy intake, physical activity, and body weight with energy expenditure measured by 4 days of heart rate monitoring with individual calibration of the relationship between heart rate and oxygen consumption. METHODS: Volunteer sub-study of 97 men and women (mean ages 54 and 51 years respectively) within the European Investigation into Cancer (EPIC) study in Norfolk (UK). Dietary assessment of energy intake and physical activity was by self-report and weight was measured using standard techniques. Energy expenditure was assessed objectively by recording heart rate for 4 days following a calibration of the relationship between heart rate and oxygen consumption. RESULTS: Self-reported energy intake by 7-day diary (mean 8.5 MJ/day) and food frequency questionnaire (FFQ) (mean 8.8 MJ/day) were significantly lower than objectively measured total energy expenditure (mean 11.2 MJ/day). The deattenuated partial correlations between total energy expenditure were 0.33 (7-day diary), 0.34 (FFQ), 0.50 (physical activity), and 0.56 (weight). Weight accounted for 31% (deattenuated) of the sum of squares about the mean of true energy intake after adjusting for age and sex. With the addition of self-reported physical activity, the model was significantly improved (R2 = 0.57). Adding energy either assessed by the diary or FFQ did not improve the model. CONCLUSIONS: The results presented here indicate that to adjust for energy intake, for the purpose of replicating an isocaloric experiment in an observational epidemiological study, one would do considerably better adjusting for weight and physical activity, than adjusting for energy intake estimated from an FFQ.

Body Weight↗

PubMed1994

Total energy expenditure and energy intake in the pre-school child: a comparison.

In a cohort (n 81) of healthy children aged 1.5-4.5 years, measurements of energy intake and energy expenditure were compared. Energy intake was calculated following a 4 d weighed record completed by the mother or guardian of the child. Total energy expenditure was measured using the doubly-labelled water technique. Mean energy intake and expenditure in the cohort were 4773 kJ/d and 4928 kJ/d respectively. The mean relative bias between the techniques was 154 kJ/d. In the older children (3.5-4.5 years) the mean relative bias was only 37 kJ/d. At the population level the measurements of energy intake and energy expenditure were extremely close, and the study has provided sufficient confidence in weighed intake methodology for it to be used in a major nationwide study of dietary intake and nutritional status of children aged 1.5-4.5 years.

Age Factors↗

PubMed2002

Participant characteristics associated with errors in self-reported energy intake from the Women's Health Initiative food-frequency questionnaire.

BACKGROUND: Errors in self-reported dietary intake threaten inferences from studies relying on instruments such as food-frequency questionnaires (FFQs), food records, and food recalls. OBJECTIVE: The objective was to quantify the magnitude, direction, and predictors of errors associated with energy intakes estimated from the Women's Health Initiative FFQ. DESIGN: Postmenopausal women (n = 102) provided data on sociodemographic and psychosocial characteristics that relate to errors in self-reported energy intake. Energy intake was objectively estimated as total energy expenditure, physical activity expenditure, and the thermic effect of food (10% addition to other components of total energy expenditure). RESULTS: Participants underreported energy intake on the FFQ by 20.8%; this error trended upward with younger age (P = 0.07) and social desirability (P = 0.09) but was not associated with body mass index (P = 0.95). The correlation coefficient between reported energy intake and total energy expenditure was 0.24; correlations were higher among women with less education, higher body mass index, and greater fat-free mass, social desirability, and dissatisfaction with perceived body size (all P < 0.10). CONCLUSIONS: Energy intake is generally underreported, and both the magnitude of the error and the association of the self-reporting with objectively estimated intake appear to vary by participant characteristics. Studies relying on self-reported intake should include objective measures of energy expenditure in a subset of participants to identify person-specific bias within the study population for the dietary self-reporting tool; these data should be used to calibrate the self-reported data as an integral aspect of diet and disease association studies.

Aged↗

PubMed2005

Is energy intake underestimated in nondialyzed chronic kidney disease patients?

OBJECTIVE: To evaluate whether energy intake of nondialyzed chronic kidney disease (CKD) patients is underestimated. DESIGN: Cross-sectional study. SETTING: Outpatient clinic of the Federal University of Sao Paulo, Oswaldo Ramos Foundation. PATIENTS: One hundred and thirty-one nondialyzed CKD patients (86 male, 66%; body mass index [BMI] 26 +/- 4.21, mean +/- standard deviation) were included. Body weight change was evaluated after 6 to 12 months in 59 patients of the entire group. METHODS: Energy intake was evaluated using 4-day food diaries (3 weekdays and 1 weekend day), and resting energy expenditure (REE) was measured by indirect calorimetry. The ratio of energy intake to REE (EI/REE) was used to evaluate the accuracy of the recorded energy intake. An EI/REE ratio below 1.27 was used to identify patients who were underreporting their current energy intake. RESULTS: The majority of the patients reported an energy intake substantially below the recommendation (22.4 +/- 7.15 kcal/kg/d) and had an EI/REE ratio lower than 1.27. In patients with a BMI >or= 25, the mean EI/REE ratio was significantly lower than that of patients with a BMI < 25 (1.01 +/- 0.28 versus 1.27 +/- 0.42, P < .01, respectively). In addition, only in the group with higher BMI was the mean ratio indicative of underreporting. When the body weight of a subgroup of patients (n = 59) was evaluated after 7.9 +/- 2.4 months, it was observed that the subgroup of patients who maintained or gained body weight had a mean EI/REE not compatible with this condition (1.13 +/- 0.38). The low ratio, despite increasing or maintaining body weight, is highly suggestive of underreported energy intake. CONCLUSION: Energy intake of nondialyzed CKD patients seemed to be underestimated and was more pronounced in overweight and obese patients.

Body Mass Index↗

PubMed1991

Rapid orocecal transit in chronically active persons with high energy intake.

Although chronic physical activity by humans can raise energy requirements and energy intake severalfold above sedentary levels, whether these increases alter digestive strategy remains unknown. To investigate this possibility, food passage rate (mouth-to-large intestinal lactulose transit) and absorption (xylose) were compared in a cross section of young men chosen to represent a wide range of daily physical activity and food intake. In 20 men (energy intake 1,272-5,342 kcal/day), resting mouth-to-cecum transit was faster in high caloric consumers (r = -0.69, P less than 0.01). In contrast, xylose absorption (n = 26; measured either as urinary xylose excretion or integrated breath H2 production from the sugar) was unrelated to food intake. Dietary fiber intake was uncorrelated with energy intake. This apparent human digestive strategy of rapid transit across the gut absorptive surface, without a sacrifice in absorption, parallels the adaptations made by several animal species similarly faced with increased energy demand at constant fiber intake. We therefore conclude that the hyperphagia of chronic exercise in humans may be linked with significant gastrointestinal adaptations.

Adaptation, Physiological↗

PubMed2000

Influence of dietary lysine and energy intakes on body protein deposition and lysine utilization in the growing pig.

A serial slaughter study was conducted to determine the effects of true ileally digestible lysine (IDLys) intake and metabolizable energy intake (MEI) on whole-body protein deposition (PD) and dietary lysine utilization in pigs between 45 and 75 kg live weight (LW). Conventional N balances were determined at the start and end of the serial slaughter study. Semisynthetic diets based on casein and cornstarch provided protein-bound lysine to support protein depositions of approximately 70% (Lys70%, IDLys 11.1 g/d) or 90% (Lys90%, IDLys 13.2 g/d) of a determined maximum PD. During the serial slaughter study and at Lys70%, pigs were fed one of six levels of MEI ranging from 14.1 to 23.5 MJ/d; at Lys90%, pigs were fed one of seven levels of MEI ranging from 15.6 to 26.4 MJ/d. The serial slaughter study and N balances indicated that MEI and IDLys had independent effects on PD and lysine utilization. Lysine utilization (calculated as the fraction of absorbed available lysine, over and above maintenance lysine requirements, that was retained in body protein) and PD increased with increasing MEI until plateau values were reached. At the plateaus, PD was determined by lysine intake. When lysine intake determined PD, lysine utilization did not decline (P > 0.10) with increasing lysine intake. Based on the N balance study, there was no effect (P > 0.1) of LW on lysine utilization. The marginal efficiency of using absorbed available lysine for PD was 0.75 and was not affected by LW, MEI, or IDLys.

Animal Feed↗

PubMed1981

Energy intakes on sledging expeditions.

1. Previous measurements of energy intake on sledging journeys in Antarctica have given a mean intake of 14.2 MJ (Acheson, 1974; Campbell, 1975), markedly lower than values reported earlier (see Edholm & Goldsmith, 1966). The technique used (individual weighed-diet survey) was more detailed and could be assumed to be more accurate than most of the earlier work where intakes had been largely inferred from the known energy content of food boxes. In the present study an individual weighed-diet survey was carried out on male subjects during a summer manhauling journey on the east coast of Greenland. 2. Mean daily energy intake of six subjects over 33 d travelling was 16.5 MJ. Mean weight loss was 2.3 kg, probably accounted for entirely by fat loss. Weight loss occurred despite the presence of excess food. Mean daily energy intake rose gradually but persistently over the 5 weeks of the journey despite a constant level of activity and to 20.1 MJ during the 4 d rest at the end of the journey. 3. Intakes were thus higher than those found in the earlier Antarctic studies (Acheson, 1974; Campbell, 1975) but not as high as intakes reported previously (see Edholm & Goldsmith, 1966). The fact that weight loss occurred despite the presence of excess food was ascribed to the monotonous nature of the diet. The fact that energy intake rose persistently over the 5-week study period may imply that a new state of balance of intake and expenditure was reached.

Adult↗

PubMed2004

Underreporting of energy intake among Japanese women aged 18-20 years and its association with reported nutrient and food group intakes.

OBJECTIVES: To evaluate the ratio of energy intake to basal metabolic rate (EI/BMR) among young female Japanese adults, and to compare the lifestyle and dietary characteristics between relatively low and high reporters. DESIGN: Dietary intakes were assessed over a 1-month period with a validated, self-administered, diet history questionnaire, and lifestyle variables were assessed by a second questionnaire designed for this survey. The ratio of EI/BMR was calculated from reported energy intake and estimated basal metabolic rate. SUBJECTS: In total, 1889 female Japanese university students aged 18-20 years who were enrolled in dietetics courses. RESULTS: Ninety-five per cent of the subjects were classified into a non-obese group (body mass index (BMI) <25 kg m(-2); mean+/-standard deviation (SD): 20.8+/-2.6 kg m(-2)). EI/BMR was 1.43+/-0.40 (mean+/-SD). Sixty-eight per cent of the subjects showed an EI/BMR level below the possibly balanced value of 1.56, 37% showed EI/BMR below the minimum survival value of 1.27 and 2% of the subjects showed EI/BMR exceeding the maximum value for a sustainable lifestyle of 2.4. BMI, body weight and BMR decreased significantly with the increase in EI/BMR (P<0.001). The percentage of energy from carbohydrate was significantly higher, whereas those from fat and protein were significantly lower, among the lower EI/BMR groups. As for food groups, a significantly declining trend from the lowest to the highest EI/BMR groups was observed for cereals. CONCLUSION: Underreporting, rather than overreporting, of energy intake was predominant in this relatively lean Japanese female population. BMI was the most important factor affecting the reporting accuracy of energy intake.

Adolescent↗

PubMed2006

Larger portion sizes lead to a sustained increase in energy intake over 2 days.

OBJECTIVE: We tested the effect on energy intake of increasing the portion size of all foods and beverages served over 2 consecutive days. DESIGN: The study used a randomized crossover design. SUBJECTS/SETTING: Subjects were 32 adults from a university community. INTERVENTION: For 2 consecutive days in each of 3 weeks, subjects ate their main meals in a controlled setting and were given snacks for consumption between meals. We used the same two daily menus each week, but varied the portion sizes of all foods and beverages served in a given week (either 100%, 150%, or 200% of baseline amounts). MAIN OUTCOME MEASURES: Energy intake and ratings of hunger and satiety were measured. STATISTICAL ANALYSES PERFORMED: A linear mixed model with repeated measures was used. RESULTS: There was a significant effect of portion size on energy intake in both men and women (P<0.0001). Increasing portions by 50% increased daily energy intake by 16% (women: 335 kcal/day; men: 504 kcal/day), and increasing portions by 100% increased intake by 26% (women: 530 kcal/day; men: 812 kcal/day). Energy intake did not differ between the 2 days of each week. Daily ratings of fullness were lowest in the 100% portion condition (P=0.0004), but did not differ significantly in the 150% and 200% conditions. CONCLUSIONS: Increasing the portion size of all foods resulted in a significant increase in energy intake that was sustained over 2 days. These data support suggestions that large portions are associated with excess energy intake that could contribute to increased body weight.

Adult↗

PubMed1991

Energy-intake restriction and diet-composition effects on energy expenditure in men.

Eight men were fed at maintenance for 2 wk, followed by 4 wk at 50% of maintenance, then 1 wk at maintenance. The diets were formulated to contain either 40% or 20% of energy from fat. Daily energy expenditure (24-h EE) was determined by indirect calorimetry at the end of the 2-wk maintenance period; on days 1, 7, and 28 of reduced energy intake; and on days 1 and 7 of refeeding. During the reduced-energy period, body weight decreased from 96.6 to 91.5 kg and body fat decreased from 30.4% to 27.7%. There were no significant differences in 24-h EE or energy requirements per unit body weight due to diet composition or weight loss. Maintenance metabolizable-energy (ME) requirement averaged 31.0 kcal/kg body wt. Overall, the efficiency of ME use relative to body stores was 0.87 and was greater for high-fat than for low-fat diets. There was some evidence of an increase in the efficiency of energy use of body stores after weight loss. Substrate use reflected diet composition and energy-balance status independent of changes in body composition.

Adult↗

PubMedDate not supplied

[Nutrient and energy intake in adolescents from a public school]

OBJECTIVE: To assess the average intake of energy, protein, calcium, iron, vitamins A and C in adolescents. METHODS: Cross-sectional study in a high school in São Paulo, Brazil, with 92 students, both males and females, aged between 11 and 17. The sample was chosen by a systematic statistical selection. The food intake was determined by 24-h diet recall and compared with the National Research Council recommendation (1989). RESULTS: The average intake of energy, proteins and vitamin C by both males and females was higher than the recommendation. The average iron intake by males was higher than the recommendation and more than 80% in females. The average calcium intake by males was less than 70% and less than 50% in females. CONCLUSIONS: Low average intake of calcium and high average intake of energy were observed.

Journal Article↗

PubMed2004

Underreporting of energy intake from a self-administered food-frequency questionnaire completed by adults in Montreal.

BACKGROUND: Energy intake determined from self-reported dietary assessment methods may be underreported. Therefore, it is important that such methods be validated against another with known validity for energy intake or energy expenditure. METHODS: We investigated potential underestimation of energy intake obtained from our semi-quantitative food-frequency questionnaire (FFQ) administered between 2000 and 2001 in the metropolitan area of Montreal, Canada. The study population included 246 adults aged 18 to 82 years. The ratio of energy intake to estimated basal metabolic rate (EI/BMR) was used to assess underreporting and physical activity was determined from self-administered questions. Comparison of the EI/BMR ratio with the Goldberg statistical cut-off allowed us to detect individuals who were low energy reporters (LERs). LERs and non-LERs were compared to determine if they differed on sociodemographic, anthropometric and lifestyle variables. RESULTS: The EI/BMR ratio was 1.26 for men and 1.32 for women. LERs represented 43% of the sample of individuals. Male LERs accounted for 54% compared with 35% among females. Underreporting of energy intake was highest in men and individuals who were older, heavier, with higher body mass index and lower education level. A higher proportion of male LERs perceived their financial situation as adequate while a greater proportion of female LERs considered themselves poor. CONCLUSION: Our data suggest that underreporting of energy intake from the FFQ was considerable and may bias dietary interpretation. As this was uneven across the sample, it is crucial to recognise the characteristics of LERs in order to increase the validity of reported energy intake.

Adolescent↗

PubMed1998

Assessment of energy intake underreporting by doubly labeled water and observations on reported nutrient intakes in children.

OBJECTIVE: To compare reported energy intake with energy expenditure using doubly labeled water (DLW). Additionally, we compared reported nutrient intakes of our subject population with national survey population data from the third National Health and Nutrition Examination Survey (NHANES III). DESIGN: This was a cross-sectional study of children, balanced by race and gender, primarily characterized by 4 body types: lean, obese, centrally fat, or peripherally fat. SUBJECTS/SETTING: Children (n=118; mean age=10 years) kept 8-day food records, with nutritionists recording weekday school lunch intakes. These subjects, assisted by their parents, recorded all breakfasts, dinners, snacks, and weekend lunches. STATISTICAL ANALYSES PERFORMED: Data were analyzed using least squares analysis of variance with the general linear models procedure. Tukey's test was used for multiple comparisons of predicted treatment means. RESULTS: Mean daily energy intake was underreported by 17% to 33% of energy expenditure. The tendency to underreport increased with age. Underreporting occurred in all groups and subgroups studied. Reported mean intakes of vitamin A, vitamin E, vitamin B-6, calcium, zinc, and copper were less than 70% of the Recommended Dietary Allowance (RDA) for African-American girls, whereas African-American boys reported similarly low intakes of copper. On average, white girls reported intakes less than 70% of the RDA for zinc and copper, whereas white boys reported low intakes of copper (60% of the RDA). Reported intakes in general were somewhat lower than those reported in NHANES III. APPLICATIONS/CONCLUSIONS: Dietetics professionals may modify the nutritional advice they give to patients/subjects based on food intake records and other data. For children, particularly, it is imperative that ethnic and gender differences be taken into consideration and that all foods eaten be accounted for as much as possible.

Black or African American↗

PubMed1997

Endurance training with constant energy intake in identical twins: changes over time in energy expenditure and related hormones.

The effects of exercise training and of its interaction with the genotype on components of energy expenditure and related hormones were examined in young male monozygotic twins. Energy intake was maintained at the pretraining level for a 93-day training period. The estimated net energy deficit induced by training was 244 MJ and was associated with a 5-kg body weight loss that was almost entirely explained by body fat loss. Resting metabolic rate (RMR) was significantly decreased by 8% after training despite the preservation of fat-free mass (FFM). Accordingly, plasma norepinephrine (NE) concentrations, NE appearance rate, and plasma levels of triiodothyronine (T3), free T3, and total thyroxine (T4) were lower after training. The energy cost of standardized exercise was also reduced after the training program. A modest to significant within-twin-pair resemblance was observed for absolute changes in the RMR, thermic effect of food, energy cost of exercise, NE clearance, and plasma concentrations of thyroid hormones. These results suggest that when exercise training is associated with a substantial negative energy balance, energy expenditure and levels of related hormones are decreased, and this effect is partly accounted for by heredity.

Adult↗

PubMed2003

Interrelation of energy intake, body size, and physical activity with prostate cancer in a large prospective cohort study.

Energy restriction reduces prostate tumor growth in transplantable tumor models in rodents, which suggests that excessive energy intake may contribute to the risk of prostate cancer. The association of total energy intake across the normal range with prostate cancer has not been consistent in epidemiological studies. We prospectively evaluated the joint associations of energy intake and body size or physical activity with prostate cancer. Participants were 46786 male health professionals ages 40-75 years at baseline in 1986 who were free of cancer diagnosis. Between 1986 and 2000, we documented 2896 incident prostate cancer cases (excluding stage T1a) by review of medical records and histopathology reports. Of these, 339 were metastatic or fatal cases. We used Cox proportional hazards regression to estimate the multivariate relative risk (RR) of prostate cancer associated with energy intake measured using a food frequency questionnaire, overall and stratified by body mass index, waist size, physical activity, as well as by age and family history of prostate cancer. There was no association between energy intake and total prostate cancer incidence. However, a modest increased risk of metastatic or fatal disease with energy intake was suggested [RR comparing extreme quintiles: 1.38, 95% confidence interval (CI) 0.96-1.98, P(trend) = 0.06]. This association was most pronounced in men with a lower body mass index (in stratum < 24 kg/m(2): RR = 1.76, 95% CI 0.92-3.39; P(interaction) = 0.04), smaller waist size [in stratum or= median: RR = 1.74, 95% CI 0.93-3.26; P(interaction) = 0.09]. Also, the association of energy intake with metastatic and fatal prostate cancer was restricted to men who were younger [in stratum <or= 65 years old: RR = 2.60, 95% CI 1.26-5.39; P(interaction) = 0.04] or who had a positive family history [RR = 3.33, 95% CI 1.26-8.76; P(interaction) = 0.04]. Although energy intake is known to be imperfectly measured by questionnaire, we observed a positive association between energy intake and metastatic or fatal prostate cancer among men who were leaner, more physically active, younger, and who had a family history of prostate cancer. Our observations suggest the testable hypothesis that the elevated risk of clinically important prostate cancer in men with a high energy intake may be attributable to certain metabolic profiles that favor enhanced growth factor production over an increase in adiposity.

Aged↗