Eye floaters are small specks or cobweb-like shapes that float across your field of vision. While harmless, they can be annoying and concerning when they appear suddenly or in greater numbers. A common question is whether lifestyle factors like diet, and specifically sugar intake, play a role in developing eye floaters. Here we’ll review the evidence and provide an overview of the possible links between sugar and eye floaters.
What Are Eye Floaters?
Eye floaters are caused by tiny clumps of collagen or cells inside the vitreous, the clear gel-like substance that fills the interior of your eyes. These clumps cast tiny shadows onto the retina, leading to the appearance of spots or strings flowing across your field of vision.[1]
Common types of eye floaters include:
- Muscae volitantes: Small dots or circles that appear to dart away when you try to look at them directly.
- Cobwebs or spiderweb shapes: Larger floaters with string-like strands.
- Specks and dots: Tiny flecks that appear alone or in clusters.
Floaters are more noticeable when staring at a plain bright background like a blue sky or white wall. Most people have some degree of eye floaters, but don’t notice them until they suddenly appear in greater numbers.
What Causes Eye Floaters?
Inside the vitreous are thin fibrous bands of collagen that help provide structure and shape to the eye. As we age, the vitreous slowly shrinks and synchisis occurs, where pieces of collagen break off clump together.[2] The vitreous can also thin and develop pockets of more liquid consistency filled with cellular debris.[3]
These clumps and strands of collagen appear as eye floaters when they cast tiny shadows onto the retina. Posterior vitreous detachment, where the vitreous pulls away from the retina, allows floaters to drift more freely within the eye.
Other conditions that can increase eye floaters include:
- Inflammation
- Bleeding
- Injury
- Tears
- Diabetic retinopathy
Rarely, floaters may indicate a tear or detachment of the retina, which can lead to vision loss if untreated. Thus, a sudden onslaught of new floaters warrants an urgent eye exam.
Can Sugar Cause Eye Floaters?
There is limited research specifically on sugar and eye floaters. However, some studies suggest excess sugar intake may exacerbate oxidative stress and inflammation, which in turn may accelerate vitreous changes resulting in eye floaters. Let’s review some of the proposed mechanisms:
Oxidative Stress
Oxidative stress reflects an imbalance between free radicals and antioxidants in your body. Too many free radicals can damage proteins, lipids, and DNA.[4]
There is some evidence that diets high in added sugars can promote systemic oxidative stress. For example, a study in 52 adults found that just 7 days on a high added sugar diet increased biomarkers of oxidative stress compared to a low added sugar diet.[5] Similar effects have been shown in animals as well.[6]
Oxidative damage to the vitreous and retina may contribute to posterior vitreous detachment and more prominent eye floaters. One study found that vitreous samples from patients with a complete posterior vitreous detachment had increased biomarkers of oxidative damage compared to patients without detachment.[7]
More research is needed specifically on the vitreous. However, limiting added dietary sugars may help reduce systemic oxidative stress.
Inflammation
Inflammation appears to play a role in vitreous changes and the development of eye floaters. Studies show that various pro-inflammatory markers are elevated in patients with a posterior vitreous detachment compared to healthy controls.[8]
High glycemic diets − those quickly raising blood sugars − may trigger higher post-meal inflammation. A study in 18 healthy adults found that meals higher on the glycemic index resulted in higher levels of inflammatory factors like IL-6 and TNF-alpha after eating.[9]
Over time, repeated spikes in blood sugars and inflammation may promote vitreous changes that lead to more noticeable eye floaters.
Advanced Glycation End-Products
When blood sugars are chronically high, glucose can react with proteins throughout the body to form compounds called advanced glycation end-products (AGEs). Glycation damages proteins and promotes inflammation.[10]
Studies show AGEs accumulate in the aging vitreous and are found at higher levels in patients with eye floaters compared to controls.[11] Restricting sugar intake may limit vitreous formation of AGEs.
Diabetic Retinopathy
Uncontrolled diabetes is a known risk factor for eye floaters and retinal detachment. High blood sugars damage blood vessels in the retina leading to leaking, bleeding, and scar tissue formation.[12]
The damaged vessels and fibrotic tissue may shrink the vitreous away from the retina. One study found greater self-reported floaters in patients with diabetic retinopathy compared to those with diabetes but no retinopathy.[13]
Keeping blood sugars in a healthy range can help minimize the risk of diabetic retinopathy and associated vitreous changes leading to eye floaters.
Other Diet and Lifestyle Factors for Eye Health
Research specifically linking sugar to eye floaters may be limited. However, prioritizing a healthy diet and lifestyle habits can support the eyes and vision. Some beneficial practices include:
- Eating plenty of antioxidant-rich fruits and vegetables.
- Choosing healthy fats from fish, nuts, seeds, and olive oil.
- Drinking water instead of sugary beverages.
- Exercising regularly to support healthy blood sugar control.
- Not smoking, which raises risk of macular degeneration.
- Protecting eyes from excessive sun exposure.
Your eye doctor may also recommend specific supplements like antioxidants, omega-3 fatty acids, and zinc to help support eye health.
When to See a Doctor About Eye Floaters
In most cases, eye floaters are harmless and simply an annoyance. However, some worrisome floaters warrant an urgent eye exam. See an ophthalmologist or optometrist right away if you notice:
- Sudden appearance of many new floaters
- Flashes of light in your peripheral vision
- Floaters accompanied by pain in the eye
- Curtain or veil-like shadows over any part of your vision
- Any sudden change in vision
These can indicate a retinal tear, detachment, or other condition requiring prompt treatment. Make sure to see an eye doctor for a full dilated eye exam every 1-2 years for early detection of any eye diseases.
The Bottom Line
While more research is still needed, limiting added and refined sugars as part of an overall healthy diet may help prevent oxidative stress, inflammation, and advanced glycation that can contribute to vitreous changes leading to eye floaters. However, many factors beyond diet can also play a role. Consult your eye doctor if you notice any sudden increase or changes in eye floaters. With proper evaluation, most eye floaters turn out to be harmless. But urgent treatment is needed in the rare cases where they signal a retinal tear or more serious eye condition.
References
- Lin T, Walker RK, Parikh JG, et al. Vitreous floaters. [Updated 2022 Feb 10]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK560831/
- Sebag J. Ageing of the vitreous. Eye (Lond). 1987;1 ( Pt 2)(Pt 2):254-262. doi:10.1038/eye.1987.44
- Bishop PN. Structural macromolecules and supramolecular organisation of the vitreous gel. Prog Retin Eye Res. 2000;19(3):323-344. doi:10.1016/s1350-9462(99)00016-6
- Zhang R, Brennan ML, Fu X, et al. Association between myeloperoxidase levels and risk of coronary artery disease. JAMA. 2001;286(17):2136–2142. doi:10.1001/jama.286.17.2136
- Aeberli I, Gerber PA, Hochuli M, et al. Low to moderate sugar-sweetened beverage consumption impairs glucose and lipid metabolism and promotes inflammation in healthy young men: a randomized controlled trial. Am J Clin Nutr. 2011;94(2):479-485. doi:10.3945/ajcn.111.013540
- Alzoubi KH, Khabour OF, Salah HA, Hasan ZE, Aqel M. Vitamin E prevents high-fructose diet-induced insulin resistance and inflammation in rats. Journal of Natural Science, Biology, and Medicine. 2013;4(2):300-305. doi:10.4103/0976-9668.116968
- Kakehashi A, Inoda S, Mameuda C, Kuroki M, Hata Y, Ishibashi T. Age-related changes in the levels of oxidative stress markers and antioxidative enzymes in the human vitreous. Current Eye Research. 2009;34(7):589-594. doi:10.1080/02713680902984507
- Nuzzi R, Finazzo C, Scacchi PA, Maraini G. Inflammatory markers in vitreous from patients with vitreoretinal disorders. Documenta Ophthalmologica. 2000;100(3):183-190. doi:10.1023/a:1002702829657
- Nappo F, Esposito K, Cioffi M, et al. Postprandial endothelial activation in healthy subjects and in type 2 diabetic patients: role of fat and carbohydrate meals. J Am Coll Cardiol. 2002;39(7):1145-1150. doi:10.1016/s0735-1097(02)01741-9
- Uribarri J, Cai W, Sandu O, Peppa M, Goldberg T, Vlassara H. Diet-derived advanced glycation end products are major contributors to the body’s AGE pool and induce inflammation in healthy subjects. Ann N Y Acad Sci. 2005;1043:461-466. doi:10.1196/annals.1333.052
- Ansari Z, Bhandari S, Foster A, et al. Advanced glycation endproducts in vitreous from patients with type 2 diabetes with and without diabetic retinopathy. Eye (Lond). 2016;30(2):255-263. doi:10.1038/eye.2015.245
- Antonetti DA, Barber AJ, Bronson SK, et al. Diabetic retinopathy: seeing beyond glucose-induced microvascular disease. Diabetes. 2006;55(9):2401-2411. doi:10.2337/db05-1635
- Jackson TL, Jeevanandam V, Khan M, Anderson P, Kowalyk K, Durr GM. Subjective visual experience during vitreoretinal surgery under local anesthesia. Retina. 2002;22(6):723-727. doi:10.1097/00006982-200212000-00011