Link Between Dietary Intake and Diabetic Retinopathy: A Systematic Review
Overview of Diabetic Retinopathy
A recent systematic review published in PLOS One examined the correlation between dietary intake and diabetic retinopathy. This condition, a complication of diabetes, stands as a primary cause of vision loss and blindness globally. The rising incidence of diabetes has made diabetic retinopathy a significant public health issue. This condition results in damage to the blood vessels in the retina, affecting nearly all individuals with type 1 diabetes and over 60% of those with type 2 diabetes within two decades of diagnosis. Therefore, effective prevention and management of diabetic retinopathy are crucial.
Dietary Intake and Diabetes Management
Dietary practices play an essential role in diabetes care. While several guidelines exist, there is a lack of specific information regarding dietary strategies aimed at preventing and managing diabetic retinopathy. Current dietary recommendations are inconclusive about whether certain foods can increase or decrease the risk of developing this condition. Previous research has primarily focused on specific food groups or nutrients, overlooking the broader dietary context and its potential impact on diabetic retinopathy as a clinical outcome.
Research Findings
To fill this research gap, scientists assessed 31 observational and interventional studies that explored macro and micronutrient intakes, dietary patterns, and food and drink consumption concerning diabetic retinopathy. Their findings were published in PLOS One.
The Mediterranean Diet’s Protective Benefits
The study revealed that diets rich in fruits and vegetables, which are high in dietary fiber, low in glycemic index, and abundant in antioxidants, along with oily fish and adherence to a Mediterranean diet, appear to offer protective effects. These diets correlate with reduced glucose-induced retinal damage in patients at risk of developing diabetic retinopathy. The Mediterranean diet, known for its components like olive oil, red wine, and fiber, is widely regarded as one of the healthiest dietary patterns globally. It is thought to mitigate diabetic complications by addressing factors such as insulin resistance, oxidative stress, and inflammation, all of which can adversely affect the retina.
Caloric Intake and Risk Factors
Conversely, high-calorie diets were found to elevate the risk of developing diabetic retinopathy. Such diets contribute to increased metabolic stress and oxidative stress, factors that heighten the likelihood of the disease. Notably, the review did not find a specific association between carbohydrate intake and diabetic retinopathy, suggesting that the quality of carbohydrates may be more critical. Thus, focusing on carbohydrate quality alongside reducing overall caloric intake could prove beneficial for diabetes patients at risk.
Unclear Associations and Future Directions
The review also noted no significant links between sodium intake or vitamin D and diabetic retinopathy. However, the relationships between antioxidants, fatty acids, alcohol, and proteins with diabetic retinopathy remain ambiguous. The findings indicate a correlation between certain dietary components and diabetic retinopathy, emphasizing the importance of diet in preventing and managing the disease. A dietary approach that includes reducing calorie intake, increasing dietary fiber, consuming oily fish, and following a Mediterranean diet may help mitigate the risk and slow the progression of diabetic retinopathy.
Conclusion and Research Implications
The researchers concluded that additional studies are needed to validate these observations and potentially develop more informed dietary guidelines for preventing and managing diabetic retinopathy.
Written by Lacey Hizartzidis, PhD
Reference: Wong MYZ, Man REK, Fenwick EK, Gupta P, Li LJ, van Dam RM, Chong MF, Lamoureux EL. Dietary intake and diabetic retinopathy: A systematic review. PLoS One. 2018 Jan 1;13(1):e0186582. doi: 10.1371/journal.pone.0186582. eCollection 2018.