A new study reveals an association between higher dietary acid load and increased risk of depression and anxiety, particularly in women.
The research highlights the potential role of diet in mental health and wellbeing.
- Women with high dietary acid load had 20% higher odds of severe depression compared to those with low acid load.
- There was a positive association between dietary acid load and anxiety severity in the whole study population.
- Diets higher in fruits, vegetables and fiber were linked to lower acid load scores.
- High acid load diets featured more meats, grains and processed foods.
- Mechanisms like inflammation, ion channel activity changes may underlie the acid load-mental health link.
Source: BMC Psychiatry 2023
Link Between Dietary Acid Load & Mental Health
In the human body, a delicate balance exists between acids and bases.
The foods we eat can tip that balance one way or the other.
A diet high in meat, grains, cheese, and processed foods creates an acidic environment in the body, also called a high acid load.
In contrast, fruits, vegetables and plant proteins induce alkalinity, creating a low acid load.
Emerging research now suggests that higher dietary acidity may detrimentally impact mental health.
A new cross-sectional study specifically examined associations between dietary acid load and risk of depression and anxiety in over 6,000 Iranian adults.
Acid load was estimated using two validated scores – potential renal acid load (PRAL) and dietary acid load (DAL).
The higher the PRAL and DAL scores, the more acidic the diet. Mental health assessments were done using standardized depressive and anxiety symptom questionnaires.
Dietary Acid Load & Depression
The study found that women in the highest category of DAL and PRAL scores had approximately 20% higher likelihood of severe depression compared to women with the lowest acid load.
This association remained significant even after considering other influencing factors like BMI, age, marital status, chronic diseases and more.
However, no such clear associations were observed between acid load and depression in men.
Considering the whole study population, acid load did not seem to impact depression severity in a statistically meaningful way.
Dietary Acid Load & Anxiety
For anxiety, the results were slightly different.
PRAL scores showed a positive relationship with anxiety severity in the overall study group.
Participants with the most acidic diets had 13% higher odds of severe anxiety versus those with the least acidic diets.
However, the DAL score was not associated with anxiety in the whole population.
Even when split by gender, neither PRAL nor DAL showed a significant link to anxiety.
Overall, the study indicates dietary acidity may be a risk factor, especially for depression in women and anxiety to some degree in the general population.
Next, let’s explore the possible reasons behind this acid load-mental health connection.
Potential Mechanisms by Which High Acid Diets May Cause Depression & Anxiety
Chronic low-grade inflammation is a key feature of numerous physical and mental health disorders.
High acid diets are known to trigger inflammatory pathways in the body.
Acidity-induced inflammation stemming from a poor diet may ultimately impact the brain and raise depression and anxiety risks.
Ion Channel Dysfunction
Acid sensing ion channels (ASICs) play diverse roles in physiological processes related to sensory perception, neuronal signaling, plasticity and inflammation.
Dietary acid load can potentially disrupt ASIC expression and activity.
Emerging research implicates dysfunctional ASICs in depression pathophysiology.
Modifying dietary acidity may influence ASIC function and thereby mood disorders.
Diet and gastrointestinal health share an intimate connection with mental wellbeing through the microbiome-gut-brain axis.
Acidic diets alter gut microbiome profiles and gastrointestinal health, which can have ripple effects on immune, endocrine and neural pathways relevant to mood regulation.
High acid foods like processed meat and refined grains promote oxidative stress.
Meanwhile, fruits and vegetables are rich in antioxidants.
Oxidative stress and low antioxidant levels are associated with poorer mental health.
Shifting dietary acid load may impact the body’s redox balance.
Acidic dietary patterns are linked to lower intake of vital mood-supporting nutrients like minerals, fiber and plant compounds.
In contrast, alkalizing diets provide an abundance of these micronutrients.
Suboptimal nutrient intake may contribute to the mood destabilizing effects of high acid foods.
While the exact mechanisms are unclear, inflammation, ion channel changes, gut health modulation, oxidative stress and nutrient adequacy appear to play a role in the dietary acid load – mental health connection.
Is Dietary Acid Load a Risk Factor for Anxiety & Depression?
Mental health disorders like depression and anxiety represent a significant disease burden worldwide.
Lifestyle risk factors such as diet offer a promising avenue for prevention and treatment.
This new study adds to the evidence that dietary acid load may be one such modifiable risk factor, especially for depression and anxiety.
However, the cross-sectional design prevents determining causative relationships.
Long term clinical trials are needed to establish if lowering dietary acid load can improve mental health outcomes.
Confirming acid load as a risk factor can open the door to dietary interventions as safe, economical prevention and management strategies.
Dietary Patterns in the Study (Analyzed)
To delve deeper into this acid-mental health link, let’s take a closer look at the dietary intakes of the study participants across varying acid load levels:
High Acid Load Diets
Those with the top acid load scores consumed:
- More grains, meats
- Less fruits, vegetables, fiber
- Higher energy, protein, fat, phosphorus
- Lower potassium, calcium
Essentially, grains, processed meats and low micronutrient foods were staples in high acidity diets.
Refined carbohydrates and animal proteins are known to increase acid load.
Displacing plant foods reduces dietary alkalinity and antimicrobial compounds.
Overall, these acidic dietary habits echo elements of the modern Western dietary pattern.
Low Acid Load Diets
People with the bottom acid load scores ate:
- More fruits, vegetables, dairy, fiber
- Less grains, meats
- Higher potassium, calcium
- Lower phosphorus, protein
In comparison, the low acid load diets were abundant in plant foods and fiber.
Fruits and vegetables are rich in minerals that promote alkalinity.
Fiber consumption also enhances alkalinity. Plant-based proteins are less acidic than meat.
Thus, a more Mediterranean style plant-focused diet was associated with lower acidity.
This analysis gives us a clearer picture of what constitutes an acidic versus alkaline diet.
Minimizing acidic foods like processed grains and meats while maximizing produce, plant proteins and fiber is key to reducing dietary acid load.
6 Tips to Reduce Your Dietary Acid Load
Want to balance your dietary acid load to potentially support mental health?
Here are some strategies:
- Consider fruits and/or non-starchy vegetables at every meal.
- Swap refined grains for whole grains like quinoa, oats and brown rice.
- Choose plant protein sources like beans, lentils and tofu more often than meat.
- Enjoy nuts, seeds and plant-based yogurt for nutritious snacks.
- Avoid sugar-sweetened beverages and drink more tea and water.
- Season foods with lemon, apple cider vinegar and turmeric to add alkalinity.
Conclusion: Link Acidic Diet & Psychiatric Disorders
This comprehensive analysis of a new dietary acid load study offers novel insights into the links between acidic diets and risks of depression and anxiety.
Key associations were found, especially for women’s depression risk and anxiety in general.
Chronic low-grade inflammation, ion channel changes, oxidative stress and gut-brain signaling may represent potential mechanisms involved.
Though confirmation is needed, reducing dietary acidity could one day emerge as an accessible lifestyle strategy for improving mental health.
For now, balancing acid and alkaline foods with more fruits, vegetables and plant proteins may be a healthy step for body and mind.
- Paper: Dietary acid load, depression, and anxiety: results of a population-based study
- Authors: Hossein Bahari et al. (2023)