What Causes Diabetic Foot Ulcers And How To Prevent Them?

Diabetic foot ulcers are open sores or wounds that occur in about 15% of people with diabetes. They are caused by a combination of nerve damage (neuropathy), poor blood circulation, and minor injuries that go unnoticed and untreated. Prevention focuses on daily foot inspections, proper footwear, tight blood sugar control, and prompt attention to any skin changes. Most amputations start with a foot ulcer, but the vast majority are preventable with consistent care.

What Exactly Happens Inside The Foot To Create An Ulcer?

Two main problems work together to create diabetic foot ulcers. The first is peripheral neuropathy, which is nerve damage from high blood sugar over time. When nerves are damaged, you lose sensation in your feet. You cannot feel a pebble inside your shoe, a blister forming, or a cut on your heel. A small injury that would cause a non-diabetic person to stop and treat it goes completely unnoticed.

The second problem is peripheral artery disease (PAD). High blood sugar damages blood vessel walls, making them stiff and narrow. Less oxygen and fewer nutrients reach the foot tissues. This means even a tiny cut heals slowly — or not at all. The skin breaks down, the wound deepens, and bacteria move in. The combination of no pain signal and poor blood flow is what allows a simple scratch to become a deep ulcer.

Pressure also plays a major role. When you stand or walk, your body weight presses down on the foot. In a healthy foot, you shift your weight unconsciously because you feel discomfort. A person with neuropathy does not shift. The same spot stays under pressure for hours. This constant pressure cuts off blood flow to that spot, and the tissue dies. That dead tissue is the start of an ulcer.

Who Is Most At Risk For Developing A Diabetic Foot Ulcer?

Not everyone with diabetes gets foot ulcers. The risk is much higher in certain groups. People who have had diabetes for more than 10 years are at greater risk because nerve and blood vessel damage takes time to develop. Men are slightly more likely than women to develop foot ulcers, though researchers are not entirely sure why. The CDC reports that people with poor blood sugar control — measured by an A1C above 8% — have a significantly higher risk.

Other risk factors include a history of previous foot ulcers or amputations. Once you have had one ulcer, your chance of getting another is high. People who smoke are at much higher risk because smoking constricts blood vessels and reduces oxygen delivery to tissues. Vision problems also increase risk. If you cannot see your feet clearly, you might miss a red spot, a blister, or a crack in the skin.

Foot deformities like bunions, hammertoes, or Charcot foot change the way pressure is distributed across the foot. These high-pressure spots are where ulcers tend to form. Wearing ill-fitting shoes that rub against these areas makes the problem worse. If you have any of these risk factors, daily foot checks are not optional — they are as important as taking your medication.

What Does The Research Say About What Causes Diabetic Foot Ulcers And How To Prevent Them?

Research published in the journal Diabetes Care has identified three main pathways that lead to foot ulcers: neuropathy, ischemia (poor blood flow), and trauma. Most ulcers involve at least two of these. A 2020 systematic review found that about 50% of people with diabetes who develop neuropathy will eventually develop a foot ulcer if no preventive measures are taken. That number drops significantly with consistent foot care routines.

Studies from the American Diabetes Association show that daily foot inspections reduce ulcer risk by 30% to 40%. The key is catching problems early. A small blister that is caught on day one can be treated with a bandage and rest. The same blister left alone for a week can become a deep wound requiring hospitalization. Prevention is not complicated — it is just repetitive.

Research also shows that offloading — removing pressure from the foot — is the single most effective way to heal an existing ulcer. For prevention, custom footwear that redistributes pressure has strong evidence behind it. A study in The Lancet found that people who wore therapeutic shoes designed for diabetic feet had 60% fewer ulcer recurrences compared to those who wore regular shoes.

What Are The Most Effective Ways To Prevent Diabetic Foot Ulcers?

Prevention comes down to three daily habits. First, inspect your feet every single day. Look at the tops, bottoms, between toes, and around the heels. Use a mirror if you cannot bend over easily. Look for redness, blisters, cuts, cracks, swelling, or discoloration. If you see anything unusual, do not wait — see a podiatrist or your primary care doctor that same day if possible.

Second, keep your feet clean and moisturized. Wash them with mild soap and warm water every day. Dry them thoroughly, especially between the toes where fungus can grow. Apply a diabetes-safe moisturizer to the tops and bottoms of your feet, but not between the toes. Too much moisture between toes can cause skin breakdown and infection.

Third, wear proper footwear at all times — even indoors. Do not walk barefoot, even in your own home. A small object on the floor or a rough carpet seam can cause an injury you will not feel. Wear socks that are seamless and moisture-wicking. Your shoes should have a wide toe box, soft interior, and firm sole. Many insurance plans cover therapeutic diabetic shoes with a prescription from your doctor.

What Are Common Misconceptions About Diabetic Foot Ulcers?

A common myth is that foot ulcers are caused by poor hygiene. That is not accurate. While keeping feet clean helps, ulcers are primarily caused by nerve damage and poor circulation — not dirt. Another misconception is that if your feet do not hurt, they are fine. With neuropathy, the opposite is true. No pain can mean no protection. You cannot rely on pain to tell you something is wrong.

Some people believe that home remedies like soaking feet in Epsom salts or applying hydrogen peroxide help prevent ulcers. These can actually make things worse. Soaking can dry out the skin and cause cracks. Hydrogen peroxide kills healthy tissue along with bacteria. Stick to mild soap and water. If you have an open wound, do not treat it yourself — see a healthcare provider.

Another myth is that once you have a foot ulcer, amputation is inevitable. That is false. With proper wound care, offloading, infection control, and blood sugar management, most foot ulcers heal. The key is early treatment. Waiting even a few days can turn a treatable wound into a serious infection. The International Diabetes Federation reports that 85% of diabetes-related amputations are preceded by a foot ulcer. But with prompt care, most of those amputations are preventable.

What Should You Do If You Notice A Foot Ulcer Forming?

If you see a red spot, blister, or open sore on your foot, stop walking on it immediately. Remove pressure from that area. Do not try to pop a blister or cut away dead skin yourself. Clean the area gently with saline or clean water and cover it with a sterile bandage. Then call your doctor. Do not wait to see if it gets better on its own — it will not.

Your doctor will assess the wound, clean it properly, and may prescribe antibiotics if infection is present. They will also recommend an offloading device — a special boot, cast, or shoe that keeps weight off the wound. Do not remove this device unless told to. Walking on an ulcer even for a few steps can undo days of healing. Some clinics use advanced treatments like debridement (removing dead tissue) or special dressings that promote healing.

If you have signs of infection — redness spreading from the wound, warmth, swelling, pus, or fever — go to the emergency room. Foot infections in people with diabetes can spread quickly to the bone. Osteomyelitis (bone infection) is a serious complication that often requires long-term antibiotics or surgery. Do not take risks with foot infections. They escalate faster than most people realize.