Numbness in the foot

What is numbness in the foot, and how common is it?

Numbness means losing some or all feeling in your foot because of a problem with the nerves that send signals to your brain¹. It can come with tingling, prickling or pins and needles¹. It's often linked to peripheral neuropathy (damage to the nerves in the hands, feet and arms), where numbness and tingling in the feet are main symptoms².

Ordinary pins and needles from sitting or sleeping on your foot is different. It happens when the blood supply to the nerves is cut off, and it usually passes within a few minutes³. Numbness that lasts or keeps coming back is worth getting checked.

Neuropathy affects around 1% of people, and up to 7% of older people⁴. It's more common with diabetes: about 36% of people with diabetes have it⁵. These figures are for nerve damage, not for numb feet on their own.

What can cause numbness in the foot?

Diabetes is the most common cause of nerve damage in the feet, and alcohol is the next most common⁶. Other causes include:

• low vitamin B12 or other vitamins, an underactive thyroid, and nerve injury from an accident or surgery⁷;
• some infections (such as shingles), kidney or liver disease, some cancers and inherited conditions⁸;
• immune conditions such as rheumatoid arthritis or coeliac disease⁸;
• chemotherapy⁶.

In some people (about 20–30%) no cause is found⁴. Your symptoms alone can't tell these causes apart, so persistent numbness is best checked by a doctor rather than self-diagnosed.

Before your appointment, note when the numbness started, whether it's constant or comes and goes, and whether it affects one foot or both. Also list your medicines, your alcohol intake, any diabetes or thyroid problems, recent injuries or surgery, and any family history of nerve problems.

How is the cause found?

A doctor will ask about your symptoms and examine you, and may refer you for tests to find the cause¹. The examination may include testing your sense of vibration and touch, and your reflexes. Tests may include blood tests, nerve conduction studies, ultrasound and MRI⁹.

For people with diabetes, checks using vibration, ankle reflexes and a thin nylon filament (a monofilament) pressed against the foot give fairly consistent results between examiners and are supported for screening¹⁰. A normal filament result doesn't rule out nerve damage¹⁰. If it's normal but your numbness continues, ask about further assessment. Finding the cause early gives a better chance of limiting damage².

What can I do myself, and what helps first?

See your GP early so the cause can be found and treated: early treatment increases the chance of controlling symptoms and preventing more problems¹¹. Which treatment suits depends on the cause.

Protecting your feet is the main thing you can do yourself. With less feeling, you may not notice stepping on something sharp, or a small blister or sore¹¹. Skin damage can quickly become a deep injury or infection without any pain⁷. Reduced feeling can also raise the risk of burns and falls¹¹⁹.

In adults with diabetes who have had a foot ulcer, therapeutic footwear that relieves pressure under the foot, and daily checks of foot skin temperature, help prevent ulcers on the sole coming back¹². If that's you, ask your podiatrist or doctor about it. These findings are for adults with diabetes, so may not apply to numbness from other causes.

What helps if that isn't enough?

Treatment depends on the cause, so decisions are best made with your doctor. Delayed or improper treatment of nerve problems can lead to severe impairment, so timely diagnosis and teamwork between professionals matter¹³. If the cause of a nerve injury isn't clear, MRI and ultrasound may find nerve damage that needs surgery¹⁴.

If the cause is unclear or your symptoms are changing, ask your GP whether a referral to a neurologist (a doctor who treats conditions of the nervous system) is right for you². If symptoms get worse or affect your walking, go back to your GP rather than waiting.

Will the feeling come back, and can I stop it returning?

It depends on the cause. Nerve injuries often heal incompletely, which can lead to lasting problems with how the foot works¹³. It isn't clear yet whether any treatment restores lost feeling, so the focus is on finding the cause early and protecting your feet.

If you have diabetes, nerve damage, poor blood supply to the feet and poor blood glucose control each make it more likely that a foot ulcer will come back¹⁵. Following your podiatrist's advice on footwear and daily checks, and keeping blood glucose well managed, are sensible steps. Guidelines recommend that people with diabetes have their feet screened for loss of feeling and poor circulation at least once a year, and more often if they're at higher risk¹⁶. Everyone with diabetes needs to know the warning signs of heat, pain, redness and swelling in the foot¹⁷.