Pupil reaction test is often presented as a way to assess potential adrenal weakness at home. It is described in old naturopathy literature and is based on observing the pupil’s reaction to light.
Despite its simplicity, its accuracy as a diagnostic method is extremely low. Below are the principles of the test, the results that are typically interpreted, and the reasons why this method cannot be considered reliable.
Test Description
To conduct the test, you will need a mirror, a small flashlight, and a stopwatch.
In a darkened room, sit in front of the mirror and direct a narrow beam of light from the side onto the eye, avoiding direct light hitting the center of the pupil. The pupil’s reaction is observed in the reflection:
- direct the light from the side so that the eye is illuminated;
- observe how the pupil constricts in response to light;
- maintain the illumination and watch if the pupil remains constricted;
- if the pupil dilates, time the duration of dilation;
- compare results in repeated tests.
How Results Are Typically Interpreted
It is considered normal for the pupil to remain narrow throughout the exposure to light.
Alternative literature claims that in cases of “adrenal fatigue,” the pupil first constricts and then dilates again at the 30-45 second mark, after which it constricts again. This dilation is interpreted as weakness of regulatory mechanisms.
Why the Test Is Unreliable
Despite the popularity of the test, there is no scientific evidence supporting its accuracy.
The pupil’s reaction is regulated by the autonomic nervous system and does not directly reflect adrenal function. The diameter of the pupil is influenced by dozens of unrelated factors: stress levels, eye fatigue, caffeine, dehydration, lighting conditions, medications, neurological sensitivity, and individual characteristics of the iris. These influences are significantly stronger than any potential effect of cortisol.
Studies in ophthalmology and endocrinology do not confirm that changes in pupil reaction correlate with cortisol deficiency or reduced adrenal function. Therefore, this test cannot be used diagnostically.
What the Test Can Actually Show
Despite the lack of connection to the adrenal glands, it may indirectly reflect the state of the autonomic nervous system.
Increased sensitivity to light, unstable pupil tone, and rapid fatigue of the iris muscles can occur with disturbances in sympathetic or parasympathetic regulation, migraine conditions, or electrolyte imbalances. However, this is not specific and cannot serve as a basis for conclusions about the hormonal system.
What Methods Are Actually Informative
- 24-hour cortisol test in saliva;
- DHEA-S analysis;
- morning and evening blood cortisol;
- synthetic ACTH test;
- assessment of sodium, potassium, and overall water-salt balance.
These methods provide reliable information about the functioning of the adrenal glands and their regulating systems, which the pupil reaction test cannot ensure.
