A new study published in Nutrition Research found that adding a moderate amount of almonds to the family diet (1.5 ounces/day of whole almonds or almond butter for parents, 0.5 ounces/day for children) significantly improved overall diet quality and modulated intestinal microbiota composition in study participants.

The health benefits of almonds have been well-established and reflected in science-based dietary guidance to consume nuts regularly as part of a healthy dietary pattern, but this is the first study of its kind to investigate the effects of dietary change on digestive health and immune function in parent-child pairs. Knowing that almonds contain a combination of fiber, vitamin E, unsaturated fats3 and flavonoids, study authors wanted to explore the nuts' impact on gut microbiota, which may in turn impact immunity, inflammation and general health.

The 14-week, randomized, controlled, crossover clinical study, led by researchers at the University of Florida, was conducted in 29 healthy parent and child pairs. The majority of the parents were mothers (n=24) who were overweight and an average of 35 years old. The children were 15 boys and 14 girls who were an average of 4 years old. Parents and children ate 1.5 and 0.5 ounces of almonds and/or almond butter, respectively, on a daily basis for three weeks, as part of their usual diet, followed by a 6-week washout period and another 3-week period of following the usual diet with no almonds. Adult participants completed daily questionnaires of compliance with nut intake and weekly dietary recalls on behalf of both themselves and their child.

When parents and children ate almonds, their overall diet quality improved, as measured by increased Healthy Eating Index (HEI) scores, a standard measure of adherence to recommended dietary guidance. While at the beginning of the study, HEI scores for parents and children fell below U.S. national averages, almond consumption increased their scores to 61.4, well above national averages of 57.4 for adults 31-50 years and 54.9 for children 4-8 years). Parent and child HEI component scores increased for fatty acids, total protein, seafood and plant protein and decreased for fruit and empty calories. In addition, when eating almonds, participants also consumed significantly more vitamin E and magnesium, two nutrients commonly under-consumed by the majority of adults and children. 

Although no specific changes in immune markers were observed, almond consumption did result in detectable changes in gut microbiota, which may have a variety of health benefits. Interestingly, although children consumed only one-third of the amount of almonds compared to adults, microbiota was affected to a greater extent in their bodies. Further research done over a longer time period or with a higher consumption of almonds is needed to confirm the potential effects on immune status.

"The findings suggest that participants replaced some of their empty calorie snacks with almonds, which has important implications since snacking has become so prevalent," said Wendy Dahl, PhD, RD, associate professor at the University of Florida and contributing author to the study.