You probably know an eye exam checks whether you need glasses. Most people never think of it as a health screening. For some, it is the first test that catches something the body has been hiding.
A comprehensive dilated exam can reveal early signs of high cholesterol, liver disease and diabetes, according to University of Utah Health. All three can leave visible marks on the eyelids, the whites or the retina long before a person feels anything is wrong.
Behind the pupil sits the retina, the light-sensitive layer at the back of the eye. It is the only place in the body where a physician can look at living blood vessels and nerves without an X-ray, a scan or surgery.
High cholesterol often shows on the eyelids first
Soft, flat, yellowish lumps near the inner corner of the eyelids are called xanthelasma. According to Medical News Today, they are cholesterol deposits tied to atypical lipid levels in the blood.
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That can mean raised LDL cholesterol, low HDL cholesterol or high triglycerides. A second eye tell for cholesterol is corneal arcus, a gray-white or blue-white ring around the colored part of the eye.
Neither sign usually hurts and neither usually affects vision. Both are visible clues worth discussing with a doctor.
Yellowed whites can signal the liver
When the whites of the eyes turn yellow, a doctor thinks of jaundice. Jaundice points to a build-up of bilirubin, the yellow compound the body makes when red blood cells break down.
According to NIH News in Health, a yellowish tint on the skin or in the whites of the eyes can mean the liver is not clearing bilirubin properly. Hepatitis and cirrhosis are among the causes.
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A new yellow tint is a reason to call a doctor, not something to monitor at home.
The retina may show diabetes before a diagnosis
High blood sugar damages the tiny vessels that feed the retina. They can narrow, leak fluid or bleed. Eye specialists see that as yellow leaks and tiny red dots during a dilated exam. The condition is called diabetic retinopathy.
The early stages usually cause no symptoms, according to the National Eye Institute. The institute tells people with diabetes to get a comprehensive dilated exam at least once a year.
Retinal damage can begin during prediabetes, when blood sugar is higher than normal but not yet high enough for a formal diagnosis. For some people, the eye exam is the first test that raises the flag.
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High blood pressure leaves its own vessel pattern
Long-term high blood pressure damages the retina in a distinct way. Cleveland Clinic lists narrowed small arteries, small grayish-white cotton-wool spots and tiny red microaneurysms.
It also flags yellow deposits of fat and protein that leak from damaged vessels. Most people with the condition have no symptoms until the advanced stages, when vision can start to blur.
A routine eye exam can catch the pattern early, before vision changes set in.
When to book a comprehensive exam
A quick vision check is not the same as a comprehensive dilated exam. The dilated version uses drops that widen the pupil so the doctor can look at the retina clearly.
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University of Utah Health recommends that every adult get a comprehensive dilated eye exam by age 40, and every year or two after age 65. The National Eye Institute tells people with diabetes to book one at least once a year.
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This article is made and published by Mie Hermansen, who may have used AI in the preparation.