Scientists followed 398 older women for 15 years to see if their diet affected the tiny blood vessels in their eyes. They found that women who ate fewer starchy vegetables and fish had narrower blood vessels in their eyes. The researchers were especially interested in foods that create a compound called TMAO in the body, which might affect blood vessel health. While the results weren’t strong for the overall diet pattern, certain individual foods did seem to make a difference in eye blood vessel size over time.

The Quick Take

  • What they studied: Whether the foods women eat affect the size of tiny blood vessels in their eyes 15 years later
  • Who participated: 398 postmenopausal women with an average age of 65 years from the CAREDS study
  • Key finding: Women who ate less fish and starchy vegetables had narrower eye blood vessels, but overall diet patterns showed mixed results
  • What it means for you: Eating fish and starchy vegetables may help keep eye blood vessels healthy, but more research is needed to confirm these findings

The Research Details

This was a long-term follow-up study where researchers tracked the same group of women for 15 years. At the beginning (2001-2004), the women filled out detailed questionnaires about what they typically ate. Then, 15 years later (2016-2019), the researchers took special photographs of the back of their eyes to measure the width of tiny blood vessels. The researchers were particularly interested in foods that help create a compound called TMAO in the body, which comes from breaking down a nutrient called choline found in foods like eggs and meat.

This type of long-term study is valuable because it can show whether diet choices made years ago might affect health outcomes later. The blood vessels in the eye are similar to blood vessels throughout the body, so changes in eye blood vessels might reflect overall blood vessel health.

The study followed women for a long time, which is a strength. However, many women dropped out over the 15 years, which may have affected the results. The researchers tried to account for this using special statistical methods.

What the Results Show

The main finding was that individual food groups seemed more important than overall diet patterns. Women who ate less fish and fewer starchy vegetables (like potatoes, corn, and peas) had narrower arterioles - the tiny arteries in their eyes. When researchers used special statistical methods to account for women who dropped out of the study, they found that women with diets highest in TMAO-producing foods had slightly narrower arterioles compared to those with the lowest intake. However, this finding only appeared when using the special statistical correction, making it less certain.

The researchers didn’t find strong associations between the overall TMAO diet pattern and venules (tiny veins in the eyes). The effects they did find were relatively small and may not be clinically significant for most people.

This appears to be one of the first studies to look at long-term diet effects on retinal blood vessel size, so there isn’t much previous research to compare it to. The connection between diet and blood vessel health has been studied in other parts of the body with mixed results.

A major limitation was that many women dropped out over the 15 years, which could bias the results. The study only included postmenopausal women, so results may not apply to men or younger women. The effects found were small and may not be meaningful in real life.

The Bottom Line

Based on this study, eating fish and starchy vegetables may support healthy eye blood vessels, but the evidence is preliminary. Continue following general healthy eating guidelines that include a variety of foods including fish and vegetables.

Postmenopausal women may be most interested in these findings, but the results need confirmation in larger, more diverse groups before making specific recommendations.

If diet does affect eye blood vessel health, this study suggests effects may take many years to become apparent, so consistency in healthy eating over time is likely most important.

Want to Apply This Research?

  • Track weekly servings of fish and starchy vegetables like potatoes, corn, and peas to see if you’re getting adequate amounts
  • Consider adding one serving of fish per week and including starchy vegetables as part of balanced meals
  • Log fish and starchy vegetable intake monthly to identify patterns and ensure consistent consumption over time

This research is preliminary and should not replace medical advice. Consult with your healthcare provider before making significant dietary changes, especially if you have existing eye or cardiovascular conditions.