Dietary acid load and its association with psychological disorders, sleep quality, and mood among Iranian older adults: a cross-sectional study

BMC Public Health. 2025 Aug 22;25(1):2891. doi: 10.1186/s12889-025-24249-z.

ABSTRACT

OBJECTIVE: The rapid increase in the global elderly population poses significant mental health challenges. Dietary factors, particularly dietary acid load, are increasingly recognized as influential factors in mental health and psychological well-being. This study aims to elucidate the associations of dietary acid load with psychological disorders, sleep quality, and mood among Iranian Older Adults.

METHOD: This study included a randomly selected sample of 398 elderly individuals. Their dietary habits were examined using a validated food frequency questionnaire (FFQ). To estimate dietary acid load, three well-established indices were employed: potential renal acid load (PRAL), net endogenous acid production (NEAP), and dietary acid load (DAL). Mental health status was evaluated by applying the Iranian version of the Depression, Anxiety, and Stress Scale (DASS-21), which has been validated for accuracy. Furthermore, participants’ sleep quality and mood were assessed through the Pittsburgh Sleep Quality Index (PSQI) and the Profile of Mood States (POMS), respectively.

RESULT: In fully adjusted models controlling for demographic, dietary, and lifestyle variables (e.g., age, BMI, socioeconomic status, caffeine intake), individuals in the highest tertile of the DAL index exhibited greater levels of stress than those in the lowest tertile (OR: 3.06, 95% CI = 1.43-6.57, p = 0.003). Elevated PRAL values were also linked to increased depressive symptoms (OR: 2.18, 95% CI = 1.04-4.58, p = 0.032). Higher levels of all three dietary acid load indices were significantly associated with poorer sleep quality (p < 0.05). However, no statistically significant associations were identified between dietary acid load and either anxiety or mood status (p > 0.05).

CONCLUSION: Elderly individuals with elevated PRAL and DAL values showed increased symptoms of depression and stress, respectively. Additionally, higher dietary acid load was associated with poorer sleep quality. Prospective studies and clinical trials are needed to validate these relationships and to better understand the underlying mechanisms.

PMID:40846926 | DOI:10.1186/s12889-025-24249-z