Blood Sugar and Your Skin: Signs, Symptoms and Skin Problems

High blood sugar can affect more than your A1C—it can also affect your skin. Diabetes may contribute to dry or itchy skin, slow-healing wounds, bacterial and fungal infections, and several recognizable skin conditions.

Some skin changes are harmless, while others may be an early sign of insulin resistance or a warning that blood sugar has been running high. Knowing what to look for can help you protect your skin and recognize problems that need medical attention.¹

Quick Answer: How Does Blood Sugar Affect Your Skin?

High blood sugar can affect the skin through fluid loss, changes in small blood vessels, nerve damage and a greater susceptibility to infection. Possible signs include dry or itchy skin, slow-healing wounds, recurring infections, dark velvety patches and certain diabetes-related skin conditions.¹

Skin changes alone cannot tell you what your blood sugar level is or diagnose diabetes. However, unexplained or persistent skin problems can be a reason to talk with your healthcare provider.

Key Takeaways

• High blood sugar can contribute to dry, itchy skin and increase the risk of some skin infections.
• Diabetes can affect the nerves and small blood vessels that support healthy skin.
• Acanthosis nigricans can be a sign of insulin resistance.
• Diabetic dermopathy causes harmless brown or reddish patches, usually on the shins.
• Daily moisturizing, gentle skin care, glucose management and regular skin and foot checks can help reduce complications.
• Open sores, spreading redness, swelling, drainage or wounds that do not heal should be evaluated promptly.

How High Blood Sugar Affects Your Skin

The relationship between blood sugar and your skin involves several different mechanisms.

When blood glucose is high, the body may pull fluid from tissues as it tries to remove excess glucose through urine. This can contribute to dehydration and dry skin. Diabetes can also affect small blood vessels and nerves, potentially changing circulation and sensation in the skin.¹

Dryness itself can create another problem. When skin becomes itchy, scratching can cause small cracks or breaks in the skin barrier. These openings can make it easier for bacteria or fungi to cause an infection.

People with diabetes may also be more susceptible to bacterial and fungal skin infections, particularly when glucose levels remain high.²

Can Your Skin Show Signs of High Blood Sugar?

Yes, certain skin changes can occur when blood sugar has been high over time, but no skin symptom can tell you your actual glucose level.

Possible signs include:

• unusually dry or itchy skin
• wounds or sores that heal slowly
• recurring bacterial or fungal infections
• dark, thick or velvety patches of skin
• brown or reddish spots on the shins
• thick or waxy skin on the fingers or hands
• blisters that appear without an obvious injury

Some of these conditions also occur in people without diabetes, so a skin change should not be used to diagnose high blood sugar on its own.

If you’re unsure how your readings compare with typical ranges, see our blood sugar charts.

Common Skin Problems Associated With Diabetes

Dry, Itchy Skin

Dryness and itching are among the most common skin complaints in people with diabetes.

High blood sugar can contribute to fluid loss, while poor circulation may also play a role in itching, particularly in the lower legs.¹ Hot showers, harsh cleansers and dry weather can make the problem worse.

Using a fragrance-free moisturizer after bathing and choosing warm rather than hot water can help protect the skin barrier.

Acanthosis Nigricans

Acanthosis nigricans causes dark, thickened, velvety areas of skin, most commonly around the neck, armpits or groin.

Rather than being caused simply by poor hygiene or skin discoloration, acanthosis nigricans is strongly associated with insulin resistance and can occur in people with prediabetes or type 2 diabetes.¹

Treating the underlying insulin resistance is more important than aggressively scrubbing or attempting to bleach the affected skin.

Diabetic Dermopathy

Diabetic dermopathy, sometimes called shin spots, typically appears as small brown or reddish round or oval patches on the lower legs.

Diabetes-related changes in small blood vessels are thought to contribute to these spots. They generally do not hurt, itch or break open and usually do not require treatment.¹

Bacterial and Fungal Infections

Diabetes can make some skin infections more likely.

Bacterial infections may cause skin that becomes red, warm, swollen or painful. Common fungal infections can produce red, itchy rashes, particularly in warm, moist areas such as the groin, under the breasts, between the toes or around skin folds.²

Candida is one common cause of fungal infections in people with diabetes.

Recurring infections should not simply be treated as a cosmetic problem. They may warrant medical evaluation, especially when blood sugar has also been running high.

Diabetic Blisters

A rare condition called bullosis diabeticorum, or diabetic blisters, can cause painless blisters on the feet, legs, hands or forearms.

They can resemble burn blisters even though there was no obvious burn or injury. These blisters often heal without scarring, but they should be protected from injury and monitored for signs of infection.¹

Necrobiosis Lipoidica

Necrobiosis lipoidica is another uncommon skin condition associated with diabetes.

It can begin as small reddish or brown raised areas that gradually develop into larger, shiny patches, often on the lower legs. The affected areas may sometimes become painful, itchy or break open.

Because open lesions can become more complicated, they should be evaluated by a healthcare professional.

Digital Sclerosis

Digital sclerosis causes thick, tight or waxy skin, usually beginning on the fingers or backs of the hands. The finger joints may also become stiff and harder to move.

The condition is more common in people who have had elevated blood sugar over time.¹

Can Skin Changes Be an Early Sign of Diabetes?

Sometimes.

Skin problems can occasionally be one of the first noticeable signs of diabetes or insulin resistance.² Acanthosis nigricans is particularly important because it is associated with insulin resistance and may occur before type 2 diabetes is diagnosed.¹

Recurring infections, unexplained slow-healing wounds or persistent skin changes may also justify discussing diabetes screening with your healthcare provider, especially if you have other risk factors or symptoms.

However, diabetes cannot be diagnosed from the appearance of your skin. Blood testing is required.

Does Better Blood Sugar Control Help Your Skin?

Managing blood sugar is an important part of preventing and managing diabetes-related skin problems.

Keeping glucose within your individualized target range may help reduce excessive dryness and susceptibility to infection while also supporting overall circulation and wound healing.² Regular physical activity can also support insulin sensitivity and glucose management.

Some skin conditions may improve as the underlying metabolic problem improves, but not every mark or patch will disappear when A1C decreases. Diabetic dermopathy, for example, is harmless and may remain visible even when diabetes is well managed.

Think of glucose management as part of protecting your skin—not as a guaranteed treatment for every skin condition. If you want to understand how your A1C relates to estimated average glucose, use the A1C Calculator.

Daily Skin Care for People With Diabetes

You do not need an elaborate skin-care routine. Consistency matters more.

Use warm rather than very hot water when bathing, and choose a mild cleanser that does not excessively dry the skin. After bathing, gently pat your skin dry and apply moisturizer while your skin still retains some moisture.³

A few additional habits can make a meaningful difference:

• Keep skin clean and dry, particularly within skin folds.
• Moisturize dry areas regularly.
• Avoid putting moisturizer between the toes, where excess moisture may encourage fungal growth.
• Check your feet every day for cuts, blisters, redness, swelling or sores.
• Treat minor cuts promptly and keep them clean.
• Avoid scratching dry skin whenever possible.
• Protect exposed skin from excessive sun exposure.

If dryness continues despite regular skin care, a dermatologist can recommend products or treatments appropriate for your skin.

Pay Special Attention to Your Feet

Skin care becomes particularly important on the feet because diabetes can affect both circulation and sensation.

Neuropathy may make it harder to notice a blister, cut or pressure injury. If an unnoticed wound becomes infected or heals poorly, what began as a small skin problem can become much more serious.

Check the tops, bottoms and sides of your feet every day, including between your toes. A mirror can help you inspect areas that are difficult to see.

Contact your healthcare provider promptly if you notice an open sore, increasing redness, swelling, drainage, warmth or a wound that is not healing.³

When to See a Doctor

Many cases of mild dry skin can be managed at home, but some skin changes require professional evaluation.

Contact your healthcare provider or dermatologist if you have:

• a cut, blister or wound that is not healing
• spreading redness, warmth or swelling
• pus or other drainage
• increasing pain or tenderness
• a recurring fungal or bacterial infection
• an unexplained blister
• a new or rapidly changing skin lesion
• an open sore on your foot
• persistent itching or rash that does not improve with basic skin care

People with diabetes should be particularly cautious about wounds on the feet because reduced sensation can allow injuries to progress without causing significant pain.

FAQs About Blood Sugar and Your Skin

The Bottom Line

The connection between blood sugar and your skin is worth paying attention to. Persistent high blood sugar can contribute to dryness, itching and infections and is associated with several recognizable diabetes-related skin conditions.

Your skin should not be treated as a glucose meter, but unexplained changes can provide useful clues about your overall health.

Managing blood sugar, protecting the skin barrier, checking your skin and feet regularly and addressing wounds or infections early can help prevent small skin problems from becoming more serious.

References

1. CDC — Diabetes and Your Skin. [↩] [↩] [↩] [↩] [↩] [↩] [↩] [↩] [↩] [↩]
2. American Diabetes Association — Diabetes and Skin Complications. [↩] [↩] [↩] [↩]
3. American Academy of Dermatology — Dermatologist-Recommended Skin Care for People With Diabetes. [↩] [↩]