Diabetes often develops silently, with symptoms that many people overlook. Yet, certain signs, such as recurring skin irritations or vision problems, can reveal the disease long before medical tests. Here are the warning signs that are frequently underestimated, even by healthcare professionals.

Skin changes: a signal not to be ignored

The appearance of abnormal pigmented areas , particularly on the knees, nape of the neck, or skin folds , could indicate more than just a dermatological issue. These pigmentary changes, clinically known as acanthosis nigricans , are often a marker of chronic hyperglycemia . Excess blood glucose stimulates both melanin synthesis and keratinocyte proliferation, causing these characteristic brownish patches.

Although these symptoms may seem benign, they require medical attention, especially if they are recent or rapidly spreading. Certain measures, such as weight loss or dermatological treatments, can alleviate these symptoms, but the primary treatment focuses on normalizing blood sugar levels through appropriate lifestyle and dietary changes.

Hearing loss: a surprising link with blood sugar

Age-related hearing loss is well known. However, few people know that a decrease in hearing acuity , whether sudden or gradual, can indicate a metabolic disorder. Research shows that individuals with insulin resistance have a nearly one-third increased risk of hearing loss compared to the general population.

This phenomenon is explained by the detrimental effect of hyperglycemia on the microvessels and nerve fibers of the cochlea. When these structures are damaged, the transmission of sound stimuli to the auditory cortex becomes impaired, leading to progressive hearing loss. In the case of unusual hearing difficulties or persistent tinnitus , a blood glucose assessment should be considered in conjunction with an ENT examination.