Findings from a recent study published in Journal of Ophthalmology examined how dietary patterns relate to myopia in children and adolescents, drawing on data from a citywide eye screening program in Tianjin, China.
Researchers identified three distinct eating patterns and tested each against myopia outcomes after controlling for known confounders. Two of the three showed a statistically significant relationship with myopia risk.
Give me some background first.
Myopia prevalence is climbing fast, particularly among school-aged children in East Asia. The most commonly discussed triggers include screen time, outdoor activity, and genetics.
Diet has gotten far less attention, in part because most existing research has looked at single nutrients or specific foods rather than overall eating patterns.
- As such: Whether total dietary habits can meaningfully shift myopia risk has been largely unexplored.
Now, talk about the study.
A team from Tianjin Medical University ran a cross-sectional study using data from the Tianjin Child and Adolescent Research of Eye (TCARE) survey—a large-scale, school-based ocular screening conducted across rural, urban, and suburban districts conducted August to October 2022.
Who was included in the study?
The study initially enrolled 28,267 students aged 6 to 18. After excluding participants with missing behavioral data or abnormal dietary entries, 24,797 participants were included in the final analysis.
- The gender breakdown: 52.3% male, 47.7% female.
And how was the study conducted?
Participants’ dietary assessments were based on parent-reported food frequency questionnaires (FFQ) covering 17 food groups.
Following this:
- Researchers applied principal component analysis (PCA) to organize eating habits into three dietary patterns (A, B, and C):
- Dietary Pattern A: refined grains, eggs, fruits, red meats, dairy products, and leafy vegetables
- Dietary Pattern B: nuts, tubers vegetables, legumes, whole grains, and aquatic products
- Dietary Pattern C: fried and barbecued, fast foods, and savory snacks
- They then used binary logistic regression to test each pattern's association with myopia
Take note: Myopia was defined based on uncorrected visual acuity combined with noncycloplegic refraction, specifically a spherical equivalent refraction (SER) of ≤ −0.50 diopters (D).
Now to the findings … starting with patients’ demographics.
In general: Girls were more likely to have myopia than boys—while the following characteristics of students all contributed to higher rates of myopia (p < 0.001):
- Those in grades 7 to 12
- Those in suburban areas
- Those with parental myopia
- Those with longer daily homework time
- Those with less outdoor exercise
The study’s results were adjusted for patients’ age, sex, region, parental myopia, homework time, and outdoor exercise time.
And what were the outcomes of those dietary patterns?
Of the three dietary patterns, two reached statistical significance—for opposing reasons—after full adjustment for confounders:
Dietary Pattern B was associated with lower myopia risk.
- High adherence compared to low adherence: odds ratio (OR) = 0.933, 95% confidence interval (CI): 0.872 to 0.999, p = 0.046
Dietary Pattern C was associated with increased myopia risk
- High adherence: (OR = 1.083, 95% CI: 1.012 to 1.158, p = 0.021).
What about Dietary Pattern A?
Dietary Pattern A showed a reduced risk of myopia in unadjusted analysis for the moderate adherence group (OR = 0.907, 95% CI: 0.852 to 0.964, p = 0.002).
- However, that association disappeared after controlling for confounders—and the adjusted models found no significant relationship between Pattern A and myopia.
Let’s discuss this.
As long-term high sugar intake is known to affect blood glucose, insulin, and glucagon levels, the authors noted that elevated blood glucose and abnormal glucose metabolism may also disrupt the polyol and acetylcholine signaling pathways—which could induce refractive and axial myopia.
Worth noting: The nuts-tubers vegetables pattern overlapped considerably with established dietary frameworks, including the Planetary Health Diet and the Dietary Approaches to Stop Hypertension (DASH) diet.
- Both emphasize whole grains, legumes, vegetables, and nuts while limiting added sugars and processed foods.
Any limitations with this research?
The cross-sectional design meant causation could not be established.
- Plus: Parent-reported FFQs were subject to recall bias and may have missed certain food items, even with 17 food groups assessed.
See here for other considerations, including the use of noncycloplegic refraction, which may have overestimated myopia prevalence in children.
Expert opinion?
The authors argued that dietary modification could serve as a primary prevention strategy for myopia, and that the snacks pattern findings are consistent with earlier research linking high sugar intake to myopia risk in children.
- See here for more insights on the findings.
Take home.
While diet is rarely part of myopia counseling conversations, this study may give clinicians a reason to ask young myopic patients (and their parents) about eating habits.
- Parents looking for actionable prevention steps can be directed toward reducing ultra-processed food intake, an area with growing evidence behind it well beyond eye health.