Many things about our feet can reveal issues going on at a deeper level inside us. The good news is, we don’t have to be podiatrists to recognize when something doesn’t look right. Also, when combined with other, seemingly “mild” or innocuous symptoms, out-of-the-ordinary issues with our feet can lend evidence as to what might be going on elsewhere in the body.
Cold feet aren’t just for weddings. When feet are uncomfortably cold on a regular basis, this may be indicative of hypothyroidism (particularly if experienced along with cold hands and other symptoms of low thyroid function). When toes become painfully cold, or possibly even numb, it may indicate Raynaud’s phenomenon. Another clue to Raynaud’s would be a color change: in Raynaud’s, blood vessels in the fingers and toes constrict and narrow, resulting in reduced blood flow to these extremities, giving them a white or even blueish appearance. (It tends to happen during cold weather and/or when affected individuals are under a lot of emotional stress.) Little is known about what causes Raynaud’s, but it is separated into two categories: Primary Raynaud’s, called Raynaud’s disease, “happens on its own” and is not associated with an underlying associated medical condition, while secondary Raynaud’s, or Raynaud’s phenomenon, is a condition that results when more serious diseases reduce blood flow to fingers and toes.
Other uncomfortable sensations in the feet and toes may be indicative of more dire health issues. Feelings of numbness, or feeling like one is wearing socks or stockings when they aren’t, may be symptoms of peripheral neuropathy or diabetic neuropathy. Coldness, tingling, and “pins and needles” sensations in the feet (and hands) could be symptoms of pernicious anemia, which stems primarily from a vitamin B12 deficiency.
Ridges and lines in the toenails not due to trauma/injury might be signs of nutrient deficiencies. Iron insufficiency may result in fingernail ridges, abnormally shaped nails, or even nails that are concave in spots (called koilonychias), and this may be mirrored in the toenails. Unsightly yellowish toenails may be a sign of fungal infection (the most common cause), but they could also be a sign of compromised liver function, with jaundice causing a yellowing of skin, nails, and whites of the eyes.
Another indication of an underlying issue our feet clue us in to is enlargement of the big toe, particularly when accompanied by redness, pain, and a sensation of heat. Taken together, these may be a sign of gout. Originally thought to be due mainly to a high intake of dietary purines (high purine foods include animal proteins and beer), more recent evidence suggests that excess fructose consumption contributes to gout. Some studies suggest that overconsuming even natural fruits and fruit juices that are relatively higher in fructose compared to other fruits may also contribute to gout, so it’s not just sodas sweetened with sugar or HFCS, as are often “blamed” in such situations.
While our feet do send us these clear messages, most of these issues would occur along with other signs and symptoms. For example, numbness and tingling in the feet and toes are unlikely to be the only signs of peripheral neuropathy or pernicious anemia. And cold feet would certainly not be the only symptom of hypothyroidism a patient would experience. But for those people—and there are plenty—who tend to ignore all “the little nagging things,” until they become very serious problems, paying more attention to their feet might help hammer home the possibility that something more sinister is going on elsewhere in the body.
Feet aren’t glamorous. Unlike the adrenal glands or the gut microbiome, there isn’t a lot of buzz about them in popular health and nutrition news. But we ignore the signals they send us at our peril. by Dr. David Brady