A Randomized Study on the Effect of Dried Fruit on Acid-Base Balance, Diet Quality, and Markers of Musculoskeletal Health in Community Dwelling Adults.

OBJECTIVES: We tested whether 100 g/day of dried fruit (vs. no supplemental fruit control) for 6 months alters 24-hr urinary net acid excretion (NAE), bone resorption, weight, body composition, muscle performance, and diet quality. We explored consistency of self-selected dietary composition and potential renal acid load (PRAL). METHODS: This randomized, single-blind, 2-armed study included 83 normal- and over-weight men and postmenopausal women (age ≥50 years) on self-reported low fruit diets. Endpoints included group differences in NAE (primary), 24-hr urinary N-telopeptide (NTX), weight, body composition, muscle performance, and diet quality. RESULTS: At baseline, mean (±SD) age was 69 ± 8 years; 86% were Caucasian; body mass index was 24.5 ± 2.8 kg/m2; 46% female, and NAE was 32.4 ± 23.1 mmol with no significant baseline group differences. No significant group differences were noted in NAE (primary), NTX, weight, body composition, muscle performance or diet quality at 6 months. In the cohort as a whole, 6-month change in NAE was positively associated with change in NTX, but no significant associations were noted in other outcomes. PRAL on the day of the urine collection was positively associated with NAE. Comparison of two consecutive baseline 24-hr diet recalls revealed wide intra-individual variability in PRAL in self-selected diets in our participants. CONCLUSION: In this field study of older adults consuming self-selected diets, making one change to the diet by adding 100 g/day of dried fruit (equivalent to 4 servings per day) had no significant impact on NAE when compared to a no supplemental fruit control. This null finding may be attributable to the high day-to-day variability in consumption of foods affecting NAE. Added fruit also had no significant effect on weight, fat, muscle, or bone outcomes over a 6-month period.

Food groups associated with measured net acid excretion in community-dwelling older adults.

BACKGROUND/OBJECTIVES: Acid-producing diets have been associated with adverse health conditions. Dietary acid load can be estimated from dietary intake data, but the available methods require a full dietary assessment. We sought to identify a simpler means to estimate 24-h urinary net acid excretion (NAE), a robust measure of net endogenous acid production, using self-reported intakes of fruits, vegetables (acid-neutralizing foods), grain and/or protein (acid-producing foods) acquired by two different methods in community-dwelling older adults. Identifying food groups associated with NAE by using a method not requiring a full diet assessment could have a broad clinical application. SUBJECTS/METHODS: Fruit, vegetable, protein and grain servings/day were estimated with a widely used food frequency questionnaire (study A, n=162, 63±8 years). Differences in their intakes across NAE categories (<5, ⩾5 to <15, ⩾15 to <50, ⩾50 milliequivalents (mEq)/day) were analyzed using analysis of variance. The findings were verified in a second study, which estimated dietary intakes, using a more detailed record-assisted 24-h recall (study B, n=232, 67±6 years). RESULTS: Fruit intake was significantly associated with NAE in both studies. In study A, fruit intake was 9% lower with each categorical NAE increase (unstandardized beta=-0.21, P=0.01) and 7% lower with each categorical NAE increase in study B (unstandardized beta=-0.18; P=0.02). Grain intake was positively associated with NAE in study B only (unstandardized beta=+0.14; P=0.01). Vegetable and protein intake were not associated with NAE in either study. CONCLUSIONS: The inverse association between fruit intake and NAE suggests low self-reported fruit intake may be an indicator of acid-producing diets in older adults.

Food cravings and energy regulation: the characteristics of craved foods and their relationship with eating behaviors and weight change during 6 months of dietary energy restriction.

OBJECTIVE: To examine characteristics of craved foods in relation to dietary energy restriction (ER) with high (HG) and low glycemic load (LG) diets. DESIGN: Assessments of food cravings before and during a randomized controlled trial of HG and LG diets provided for 6 months. SUBJECTS: Thirty-two healthy, overweight women aged 20-42 years. MEASUREMENTS: Self-reported food cravings and dietary intake, body weight, weight history and measures of eating behaviors. RESULTS: Foods craved at baseline were more than twice as high in energy density as the habitual diet (3.7+/-1.5 vs 1.7+/-0.3 kcal/g; P<0.001), and on average were lower in protein (P<0.001) and fiber (P<0.001) and higher in fat (P=0.002). There were no statistically significant changes in nutritional characteristics of craved foods after 6 months of ER. There was a significant relationship between reported portion size of craved food consumed at baseline and lifetime high body mass index (r=0.49, P=0.005). Additionally, there was a significant association between susceptibility to hunger and craving frequency at baseline, and there were significant relationships between hunger score, craving frequency, strength and percentage of time that cravings are given in to after 6 months of ER. In multiple regression models, subjects who lost a greater percentage of weight craved higher energy-dense foods at month 6 of ER, but also reported giving in to food cravings less frequently (adjusted R (2)=0.31, P=0.009). CONCLUSION: High energy density and fat content, and low protein and fiber contents were identifying characteristics of craved foods. The relationships between craving variables and hunger score suggest that the relative influence of hunger susceptibility on cravings may be important before and especially after ER. Portion size of craved foods and frequency of giving in to food cravings appear to be important areas for focus in lifestyle modification programs for long-term weight loss.