Macronutrient Absorption from Almonds: the Measured Energy Value of Almonds in the Human Diet
Food Components and Health Laboratory
2011 Annual Report
1a.Objectives (from AD-416)
To measure the macronutrient digestibility and epigenetic effects of consumption of almonds as part of a controlled diet in humans.
1b.Approach (from AD-416)
ARS will conduct a randomized clinical trial to investigate the effect of almonds, a high-fat, high-fiber food on nutrient absorption and will collect samples to evaluate epigenetic effects, and the effect of almonds on pathways associated with cancer and cardiovascular disease.
This project is to measure absorption of macronutrients from almonds and to determine the energy value of these nuts. Results from epidemiological studies suggest that there is an inverse association between individuals who frequently consume nuts and body mass index, despite the relatively high energy density of nuts. Clinical studies have shown that fat from almonds and other nuts is not well absorbed; therefore, using Atwater factors for determining the energy value of almonds could result in an overestimation of the energy content. The objective of this research project was to empirically determine the metabolizable energy (ME) content of almonds. A randomized, crossover, controlled-feeding study with healthy adults (n = 9 males and n=9 females) was conducted. Almonds were fed in 3 doses as part of a controlled diet: 0 g/day (control), 42 g/day, and 84 g/day. Urine and fecal samples were collected for 7 to 10 day periods during each 3-week diet period. Urine, feces, and diet were analyzed for nitrogen, fat, total dietary fiber, ash, and combustible energy. The energy value of almonds was calculated from differences in energy excretion during the dietary treatments. The intervention and analyses were completed and study results have been presented to the sponsor. Accurate information about ME content of foods is important for reliable food labeling so consumers can make informed dietary choices. The effect of almond consumption on fecal microbiota will be determined in subsequent analyses. Activities and progress of this agreement were monitored through site visits, conference calls, and email correspondence.