The health risks to the rest of your body
It’s not the only way our choice can have a ripple effect on our body. The Telegraph’s news editor Caroline Argyropulo-Palmer’s father suffered from lockjaw as a result of wearing sandals with no heel strap. “He was waking up each morning unable to fully open his mouth, with this lasting most of the day. He went to the dentist about it thinking it was caused by his teeth somehow, and they said it was because he was clenching his jaw in his sleep and told him not to sleep on his back anymore. But that made no difference.
“Then someone who did reflexology told him it was his shoes (he was wearing an old pair of walking sandals). He bought a new pair and the lockjaw stopped.”
Branthwaite explains how restriction in your usual movement pattern due to rigidity in the ankle can cause you to push your head forward to propel your body weight forward.
“That would put strain on the two joints that connect your lower jaw to your skull and lead to it stiffening.”
Wearing a sandal that restricts our ability to walk in our normal way also increases the risk of an unexpected fall. “Styles of footwear that reduce the range of movement in the ankle mean that you tend to shuffle more leading to trips.”
Changing our shoe style changes our centre of mass, as well as the way that we use our feet, which can cause a chain reaction further up our body.
For example, people who have lower back pain may find that pain increases if they wear very flat shoes. It’s because of the natural curve, aka lordosis, of the spine, explains Branthwaite: “If you’ve not got enough ankle range of movement to be able to get your foot down flat then your pelvis will tilt accordingly to make you stand upright.”
However, if you elevate your heel and move your centre of mass anteriorly, aka forward, this enables the spine to sit more upright. “In people that have lower back pain that reduces the activity of the spinal muscles.”
How to find healthy sandals
You might see someone shuffling along in sliders, struggling to keep them on, and on the other side of the street, someone else is marching away happily in the same pair of flimsy footwear. That’s because gait is very specific to the individual.
“If the second person has enough strength and function in their feet then they will be OK,” says Branthwaite.
She sees patients who live in Birkenstocks and can’t wear anything else because they constantly wear them. The extremely flat style may also suit those with lower arches.
However, some people’s anatomy favours a higher heel incline; for example if you have a high foot-arch, a 1cm to 2cm ramp can be more comfortable.
If you want a good all-rounder, Smart recommends Teva-style sandals over flip flops: “As they offer numerous fastenings and well-structured soles. If you require further support, such as for over-pronation, Vionic sandals are a perfect choice.”
Why you need to change your sandals as you age
In general, younger people tend to be more adaptable to different types of footwear. That’s because as we age our joints become stiffer and weaker.
“Once you pass 40 the muscle protein fibres change, and connective and collagenous tissues start to alter. Then the type of shoe we choose can become more of a problem,” says Branthwaite.