For most of us, it's hard to imagine that a disease that affects how the body processes sugar could be dangerous for our feet. However, foot problems resulting from diabetes can have life-changing outcomes, including the risk of amputation.
Both type 1 and type 2 diabetes affect the feet, and other parts of the body, by compromising the blood supply to these areas.
"Diabetes can affect organs or parts of the body that are at the end of the circulatory system," explains Matthew Fitzpatrick, podiatrist from The College of Podiatry. "With diabetes the body has an inability to keep glucose levels in the system controlled."
High levels of glucose affect the complex and sensitive interplay of chemicals and enzymes in the walls of blood vessels, leading to damage. Tiny blood vessels are easily damaged, meaning blood supply to the feet and other areas, including the kidneys and eyes, may be compromised.
How does diabetes affect the feet?
When blood vessels in the feet are damaged, patients will often notice a loss of sensation - usually starting with tingling in the toes which progresses into the foot.
"It starts as a little bit of tingling, leading to absence of feeling, sometimes to the point where you could drive a knife through the foot and patients wouldn't even flinch," explains Fitzpatrick.
Compromised blood supply also means that any wounds to the foot will take longer to heal. The combination of these two factors can have devastating consequences.
"For example, if you stand on a pin, the immediate thing you do is remove your foot," explains Fitzpatrick. "If you have diabetes you could stand on burning hot coals and not know it.
"Then when you do get an ulcer or a wound, the compromised blood supply makes healing difficult, posing the risk of infection."
It's important to take this risk seriously, as infection in your foot or leg - if it cannot be controlled - carries the risk of foot or limb amputation.
"The end treatment of foot complications is sadly an amputation," explains Dan Howarth, head of care at Diabetes UK. "It's extremely harrowing, but it's important to understand that it can happen."
Who is most at risk of foot problems?
Everyone with diabetes is at risk of foot problems, although managing the disease effectively can reduce risk.
"Even patients who are fastidious with their diet and meticulous with their medication taking will still experience damage and deterioration over time, although it won't progress at the same pace," explains Fitzpatrick.
Sadly, however, many with the condition don't take the risk seriously until problems occur.
"The challenge is that when you first diagnose someone with diabetes, they don't feel anything unless their blood sugars are very high. If you have a back pain, you don't do things that make the back sore; if you have an infected cut you take steps to stop it getting worse," explains Fitzpatrick. "But with type 2 diabetes in particular, you won't necessarily see anything wrong - this is the challenge that we have."
There has been much talk in the press and online about reversing type 2 diabetes. However, according to Howarth, whilst the condition can be minimised with correct management, the term 'reversal' is misleading and can lead to patients underestimating their risk.
"We use the term 'remission' rather than 'reversal'," he explains. "In remission you still have diabetes but you don't have the symptoms. It's too soon to say whether being in remission will prevent patients from developing complications.
"We would encourage people who have been told they are in remission to continue to have their checks, including a yearly eye check, appropriate blood tests and foot screening. People with all types of diabetes, no matter what stage, require these tests in order to prevent long-term damage and to help manage their diabetes on a day-to-day basis."
How can I keep my feet healthy?
Whilst damage to the blood vessels in the feet is a problem for all people with diabetes, managing your condition well should reduce the risk. As well as following medical advice and taking prescribed medication, this means keeping a careful eye on your feet so that any potential problems can be dealt with before they worsen.
"People with diabetes should check their feet religiously, twice-daily," advises Fitzpatrick. "Top, bottom, in between the toes, all around the feet, and behind the heels for anything that might look like a break in the skin, the development of hard skin, a bump a bruise, or an injury."
Keep an eye on corns and calluses. As normal healing is impaired in diabetes, calluses can sometimes hide foot ulcers, which can get infected if not properly treated.
"If you lack the flexibility to inspect your feet manually, try putting a small mirror on the floor. Move your foot over it to see whether you can see anything untoward underneath."
Proper washing and drying
Wash your feet with soap and warm water - but make sure it's not too hot. Then dry your feet well, taking particular care between your toes. Drying your skin properly will prevent infections, such as athlete's foot, from forming.
"You also need to keep the skin supple, so it's important to moisturise the feet. Loss of blood supply and nerve damage reduces the hydration so feet then become dry. This may lead to cracking - which can become a point of infection," points out Fitzpatrick.
There are plenty of emollient creams that are suitable for people with diabetes. Some contain the ingredient urea. Using urea has been found to improve the role of the skin as a protective barrier. It has also been shown to be an effective 'keratolytic' - it helps break down the excess keratin seen in scaly skin - and a review of studies shows that it can be effective in a wide variety of conditions, including eczema and dermatitis, and has a good safety profile. You can use a low-concentration (10%) urea cream for daily maintenance, while a stronger cream (25%) can be useful for treating calluses.
Another important aspect of caring for your feet is ensuring that you wear suitable footwear. Ill-fitting shoes can lead to nail-damage, blisters, calluses or other foot problems, which can in turn lead to infection. It's worth getting your feet measured and choosing shoes that are the right fit.
Specialised footwear is also available, and for those with particular needs, certain footwear may be available on prescription. Talk with your podiatrist about your particular foot needs and make sure you follow advice carefully.
Even a small cut or injury to your foot should be taken seriously if you have diabetes. Treating the problem quickly can make a huge difference. So it's important to act quickly.
"My advice is that if you have diabetes and experience any loss of sensation in the feet and you have a wound on the foot, you should go to see a podiatrist. It's unequivocal. There is never any overkill with this, it's absolutely about stopping the problem getting worse," advises Fitzpatrick.