That headline is catchy but misleading. Your feet cannot function as a “blood sugar meter,” and foot symptoms alone cannot diagnose diabetes.
However, diabetes can damage nerves and blood vessels in the feet, sometimes causing symptoms such as: (NIDDK)
- Numbness or reduced sensation
- Tingling or “pins and needles”
- Burning or shooting pain
- Increased sensitivity to touch
- Feeling unusually cold
- Muscle weakness
- Loss of balance or coordination
- Dry or cracked skin
- Foot sores or ulcers that heal slowly
- Blisters or injuries that aren’t noticed
- Swelling or changes in the foot
- Changes in walking caused by weakness or loss of sensation
Diabetic neuropathy often affects the feet and legs before the hands and arms, but these symptoms can also have many causes unrelated to diabetes. (NIDDK Repository)
If you repeatedly experience these symptoms, the appropriate way to check for diabetes is blood-glucose testing (such as fasting glucose or HbA1c), rather than judging blood sugar from your feet.
A particularly important warning sign is a new foot wound, ulcer, infection, or black/discolored tissue, especially if sensation is reduced. Diabetes-related nerve damage can allow injuries to go unnoticed and poor circulation can make healing more difficult. (NIDDK)
