Changes in diet and lifestyle and long-term weight gain in women and men
BACKGROUND: Specific dietary and other lifestyle behaviors may affect the success of the straightforward-sounding strategy "eat less and exercise more" for preventing long-term weight gain. METHODS: We performed prospective investigations involving three separate cohorts that included 120;877 U.S. women and men who were free of chronic diseases and not obese at baseline; with follow-up periods from 1986 to 2006; 1991 to 2003; and 1986 to 2006. The relationships between changes in lifestyle factors and weight change were evaluated at 4-year intervals; with multivariable adjustments made for age; baseline body-mass index for each period; and all lifestyle factors simultaneously. Cohort-specific and sex-specific results were similar and were pooled with the use of an inverse-variance-weighted meta-analysis. RESULTS: Within each 4-year period; participants gained an average of 3.35 lb (5th to 95th percentile; -4.1 to 12.4). On the basis of increased daily servings of individual dietary components; 4-year weight change was most strongly associated with the intake of potato chips (1.69 lb); potatoes (1.28 lb); sugar-sweetened beverages (1.00 lb); unprocessed red meats (0.95 lb); and processed meats (0.93 lb) and was inversely associated with the intake of vegetables (-0.22 lb); whole grains (-0.37 lb); fruits (-0.49 lb); nuts (-0.57 lb); and yogurt (-0.82 lb) (P=0.005 for each comparison). Aggregate dietary changes were associated with substantial differences in weight change (3.93 lb across quintiles of dietary change). Other lifestyle factors were also independently associated with weight change (P<0.001); including physical activity (-1.76 lb across quintiles); alcohol use (0.41 lb per drink per day); smoking (new quitters; 5.17 lb; former smokers; 0.14 lb); sleep (more weight gain with <6 or >8 hours of sleep); and television watching (0.31 lb per hour per day). CONCLUSIONS: Specific dietary and lifestyle factors are independently associated with long-term weight gain; with a substantial aggregate effect and implications for strategies to prevent obesity.
Nuts improve diet quality compared to other energy-dense snacks while maintaining body weight
Previous studies have reported that regular nut consumption reduces cardiovascular disease (CVD) risk and does not promote weight gain despite the fact that nuts are energy-dense. However; no studies have investigated the body composition of those regularly consuming nuts compared to similar intakes of other snacks of equal energy density. This parallel study (n = 118) examined the effects of providing daily portions (~1100 kJ/d) of hazelnuts; chocolate; or potato crisps compared to a control group receiving no snacks for twelve weeks. Effects on body weight and composition; blood lipids and lipoproteins; resting metabolic rate (RMR); appetite indices; and dietary quality were compared. At week 12; there was no significant difference in any of the outcome measurements between the groups except for dietary quality; which improved significantly in the nut group. Nuts can be incorporated into the diet without adversely affecting body weight and can improve diet quality.
The effect of the addition of daily fruit and nut bars to diet on weight; and cardiac risk profile; in overweight adults
Background: The frequency of unhealthful snacking has increased dramatically over the last three decades. Fruits and nuts have been shown to have positive health effects. No study has investigated the aggregate effects of various fruits combined with nuts in the form of snack bars on cardiovascular risk factors. The aim of this randomised trial was to investigate the effects of a fruit and nut snack bar on anthropomorphic measures; lipid panel and blood pressure in overweight adults. Methods: Ninety-four overweight adults (body mass index > 25 kg m(-2) ) were randomly assigned to add two fruit and nut bars totalling 1421.9 kJ (340 kcal) to their ad libitum diet (intervention group) or to continue with their ad libitum diet (control group). Subjects underwent assessment for weight (primary outcome measure); as well as waist circumference; lipid panel and blood pressure (secondary outcome measures); before and at the end of the 8-week treatment. Results: Weight did not change from baseline after snack bar addition compared to controls (P = 0.44). Waist circumference (P = 0.69); blood pressure (systolic; P = 0.83; diastolic; P = 0.79) and blood lipid panel (total cholesterol; P = 0.72; high-density lipoprotein; P = 0.11; total cholesterol/high-density lipoprotein; P = 0.37; triglycerides; P = 0.89; low-density lipoprotein; P = 0.81) also did not change from baseline compared to controls. Conclusions: Two daily fruit and nut bars; totalling 1421.9 kJ (340 kcal); did not cause weight gain. The role of habitual snacking on nutrient dense and satiating foods on both weight over time; and diet quality; warrants further study. Satiating snacks rich in fibre may provide a means to weight stabilisation.
The effect of pistachio shells as a visual cue in reducing caloric consumption
It was hypothesized that pistachio shells left in sight as visual cues of consumption will cause individuals to consume less. A convenience sample of faculty and staff at a mid-western university (n=118) were recruited as subjects for the study. The subjects were told they were going to evaluate a variety of brands of pistachios and were surveyed at the end of each day to determine their fullness and satisfaction. The subjects were offered pistachios on their desks for an 8-h period on two separate days and were able to consume the pistachios at their leisure during that time. Subjects began each day with a sixteen ounce bowl filled with four ounces of pistachios in the shell. They were also provided with a second sixteen ounce bowl; in which they were instructed to place the empty shells from the pistachios they consumed. Every 2h throughout the day pistachios were added in two ounce increments. In condition one; the shells remained in the bowls until the end of the day; whereas in condition two; the shell bowls were emptied every 2h throughout the day. In condition one; subjects consumed an average of 216 calories. In condition two; subjects consumed an average of 264 calories; a difference of 48 calories. Subjects in condition one consumed significantly (p=.05) fewer calories; yet fullness and satisfaction ratings were not significantly (p=.05) different between conditions. Leaving pistachio shells as a visual cue to consumption may help consumers consume fewer calories. Learning outcomes: Individuals will be aware of the impact of visual cues of dietary intake on total food consumption.
In-shell pistachio nuts reduce caloric intake compared to shelled nuts
It was hypothesized that consuming in-shell pistachios; compared to shelled pistachios; causes individuals to consume less. A convenience sample of students at a mid-western university (n=140) was recruited; asking them to evaluate a variety of brands of pistachios. A survey at the end of class determined fullness and satisfaction. Subjects entering the classroom were given a 16-ounce cup and asked to self-select a portion of pistachios. Portion weight was recorded and subjects consumed pistachios at their leisure during class. At class end; pistachios remaining in the cup were weighed and total consumption by weight was determined. The caloric content of each portion was then calculated. In condition one; subjects offered in-shell pistachios consumed an average of 125 calories. In condition two; subjects offered shelled pistachios consumed an average of 211 calories; a difference of 86 calories. Subjects in condition one consumed 41% fewer calories compared to subjects in condition two (p=.01). Fullness and satisfaction ratings were not significantly different (p=.01). Caloric intake was influenced by the initial form of the food. The difference in calories consumed may be due to the additional time needed to shell the nuts or the extra volume perceived when consuming in-shell nuts.
The risk of child and adolescent overweight is related to types of food consumed
BACKGROUND/AIMS: To investigate the association between the risk of overweight and the consumption of food groups in children and adolescents. METHODS: We studied 1764 healthy children and adolescents (age 6-19y) attending 16 Seventh-Day Adventist schools and 13 public schools using a 106-item non-quantitative food frequency questionnaire from the late 1980 Child-Adolescent Blood Pressure Study. Logistic regression models were used to compute the risk of overweight according to consumption of grains; nuts; vegetables; fruits; meats/fish/eggs; dairy; and; low nutrient-dense foods (LNDF). RESULTS: The frequency of consumption of grains; nuts; vegetables and LNDF were inversely related to the risk of being overweight and dairy increased the risk. Specifically; the odds ratio (95% CI) for children in the highest quartile or tertile of consumption compared with the lowest quartile or tertile were as follows: grains 0.59(0.41-0.83); nuts 0.60(0.43-0.85); vegetables 0.67(0.48-0.94); LNDF 0.43(0.29-0.63); and; dairy 1.36(0.97; 1.92). CONCLUSION: The regular intake of specific plant foods may prevent overweight among children and adolescents.
Changes in diet and lifestyle and long-term weight gain in women and men
BACKGROUND: Specific dietary and other lifestyle behaviors may affect the success of the straightforward-sounding strategy "eat less and exercise more" for preventing long-term weight gain. METHODS: We performed prospective investigations involving three separate cohorts that included 120;877 U.S. women and men who were free of chronic diseases and not obese at baseline; with follow-up periods from 1986 to 2006; 1991 to 2003; and 1986 to 2006. The relationships between changes in lifestyle factors and weight change were evaluated at 4-year intervals; with multivariable adjustments made for age; baseline body-mass index for each period; and all lifestyle factors simultaneously. Cohort-specific and sex-specific results were similar and were pooled with the use of an inverse-variance-weighted meta-analysis. RESULTS: Within each 4-year period; participants gained an average of 3.35 lb (5th to 95th percentile; -4.1 to 12.4). On the basis of increased daily servings of individual dietary components; 4-year weight change was most strongly associated with the intake of potato chips (1.69 lb); potatoes (1.28 lb); sugar-sweetened beverages (1.00 lb); unprocessed red meats (0.95 lb); and processed meats (0.93 lb) and was inversely associated with the intake of vegetables (-0.22 lb); whole grains (-0.37 lb); fruits (-0.49 lb); nuts (-0.57 lb); and yogurt (-0.82 lb) (P=0.005 for each comparison). Aggregate dietary changes were associated with substantial differences in weight change (3.93 lb across quintiles of dietary change). Other lifestyle factors were also independently associated with weight change (P<0.001); including physical activity (-1.76 lb across quintiles); alcohol use (0.41 lb per drink per day); smoking (new quitters; 5.17 lb; former smokers; 0.14 lb); sleep (more weight gain with <6 or >8 hours of sleep); and television watching (0.31 lb per hour per day). CONCLUSIONS: Specific dietary and lifestyle factors are independently associated with long-term weight gain; with a substantial aggregate effect and implications for strategies to prevent obesity.
Prenatal fatty acid status and child adiposity at age 3 y: results from a US pregnancy cohort
BACKGROUND: Exposure to polyunsaturated fatty acids (PUFAs) in early life may influence adiposity development. OBJECTIVE: We examined the extent to which prenatal n-3 (omega-3) and n-6 (omega-6) PUFA concentrations were associated with childhood adiposity. DESIGN: In mother-child pairs in the Project Viva cohort; we assessed midpregnancy fatty acid intakes (n = 1120); maternal plasma PUFA concentrations (n = 227); and umbilical cord plasma PUFA concentrations (n = 302). We performed multivariable regression analyses to examine independent associations of n-3 PUFAs; including docosahexaenoic and eicosapentaenoic acids (DHA + EPA); n-6 PUFAs; and the ratio of n-6:n-3 PUFAs; with child adiposity at age 3 y measured by the sum of subscapular and triceps skinfold thicknesses (SS + TR) and risk of obesity (body mass index =95th percentile for age and sex). RESULTS: Mean (±SD) DHA + EPA intake was 0.15 ± 0.14 g DHA + EPA/d; maternal plasma concentration was 1.9 ± 0.6%; and umbilical plasma concentration was 4.6 ± 1.2%. In children; SS + TR was 16.7 ± 4.3 mm; and 9.4% of children were obese. In the adjusted analysis; there was an association between each SD increase in DHA + EPA and lower child SS + TR [-0.31 mm (95% CI: -0.58; -0.04 mm) for maternal diet and -0.91 mm (95% CI: -1.63; -0.20 mm) for cord plasma] and lower odds of obesity [odds ratio (95% CI): 0.68 (0.50; 0.92) for maternal diet and 0.09 (0.02; 0.52) for cord plasma]. Maternal plasma DHA + EPA concentration was not significantly associated with child adiposity. A higher ratio of cord plasma n-6:n-3 PUFAs was associated with higher SS + TR and odds of obesity. CONCLUSION: An enhanced maternal-fetal n-3 PUFA status was associated with lower childhood adiposity.