Randomized Controlled Trial Links Daily Almond Consumption to Improved Subjective Sleep Quality

A randomized controlled trial published in Frontiers in Nutrition reports that daily consumption of whole almonds over a five-month period was associated with improvements in subjective sleep quality among adults with poor sleep.¹

How Was the Study Designed?

The trial, conducted in the Mumbai Metropolitan Region of India between March 2023 and January 2025, was an open-label, parallel-arm, community-based study with blinded outcome assessment. Researchers screened 758 adults and ultimately randomized 209 participants aged 21–55 with poor sleep quality, defined by a Pittsburgh Sleep Quality Index (PSQI) score above 5 and/or an Epworth Sleepiness Scale (ESS) score above 10, to either an almond group or a control group. A total of 175 participants (88 in the almond arm, 87 in the control arm) completed the study and were included in the per-protocol analysis.

Participants in the almond group consumed 60 g of raw almonds daily (roughly 50 whole almonds), provided by the Almond Board of California, split between a mid-morning and evening snack. The control group received an isocaloric portion of Indian savory snacks matched for calories and protein. Both groups underwent polysomnography, PSQI and ESS assessments, anthropometric measurement, and blood biomarker testing at baseline and after 20 weeks.

What Did the Study Find?

After adjusting for baseline values and sex, the almond group demonstrated a lower global PSQI score (3.94 vs. 4.79; p = 0.013), higher subjective sleep efficiency (94.45% vs. 91.85%; p = 0.012), and shorter subjective sleep latency (18.46 vs. 26.29 minutes; p = 0.016) compared with the control group. Most polysomnography-derived (objective) sleep parameters did not differ significantly between groups, though wake during sleep trended lower in the almond group (p = 0.081). Among participants who achieved a clinically meaningful PSQI improvement, wake during sleep was reduced in the almond group compared with controls (p = 0.043).

Endline melatonin concentrations were higher in the almond group (250.63 vs. 206.19 pg/mL; p = 0.050). No significant between-group differences emerged for other biochemical markers, including serotonin and cortisol, nor for anthropometric outcomes such as BMI and body fat.

“Almond consumption was associated with improvements in subjective sleep efficiency and sleep continuity in adults with poor sleep quality,” the authors concluded. “These findings suggest that almonds may enhance perceived sleep quality, with slight objective improvements among responders.”

The study authors note that the trial's strengths include its randomized design, the combined use of subjective and objective sleep measures, and high adherence rates confirmed biochemically through serum vitamin E levels in the almond group. They also note limitations, including reliance on single-night polysomnography and a study population that excluded individuals with severe sleep apnea or major psychiatric conditions, which may limit generalizability. The participants were also asked to avoid regular consumption of caffeine and alcohol, and dietary confounding could not be excluded. The authors also noted that effect sizes were modest and that larger, multicenter trials are needed to confirm the findings and clarify underlying mechanisms.

The study was funded by the Almond Board of California.

What Research Background Does the Almond Board of California Provide?

Context for this study can be found on the Almond Board of California's website, which describes the organization's long-standing investment in almond-related research.² According to the Almond Board, the California almond industry has funded $89 million in research since 1973, covering farming practices, food quality and safety, and the effects of almonds on human health. The organization maintains a searchable Research Database for reports from 2021 onward, a separate legacy database for reports predating 2020, and a 2025 research update summarizing recent findings.

References

1. Desai SR, Pinto L, Halbe A, Vaidya RA, Udipi SA, Kalita S. Effects of almond consumption on sleep quality in adults: a randomized controlled trial. Front Nutr. 2026;13:1892442. doi:10.3389/fnut.2026.1892442
2. Almond Board of California. Research Home. Accessed July 29, 2026. https://www.almonds.org/research-database