Try it. Stand up, lift one foot slightly off the ground, and hold the position. If you can keep steady for at least 10 seconds, you are doing fine. But if you wobble and drop your leg too soon, experts say it could be more than just a balance problem. It might be an early red flag for dementia.Why balance matters to the brainDementia is not a single disease but a cluster of symptoms caused by the brain’s gradual decline. It’s most common in people over 65, often showing up first as memory lapses and personality shifts. But, according to neurologist Doctor Baibing Cheng, better known as Dr Bing on TikTok, your body might reveal the signs much earlier than your memory does.“Number one is the inability to stand on one leg for at least 10 seconds,” he explained in a recent video. “If you are 70 years old or younger (and have legs) you should be able to do this and if you can't do this, it's associated with an increased risk of dementia because impaired balance reflects early dysfunction in the brain regions responsible for motor control, such as the cerebellum and basal ganglia, which are also affected in neurodegenerative processes.”The science backs it upResearch published in the Journal of Alzheimer’s Disease in 2009 studied more than 680 participants. Those who couldn’t hold themselves on one leg for five seconds or more were more likely to experience cognitive decline during Alzheimer’s.And in 2015, another study researchers discovered that failing to balance for more than 20 seconds was linked to microbleeds and “silent” strokes. More than one testOf course, dementia risk isn’t only about standing on one leg. Dr Bing listed four other physical and behavioural clues that may predict future problems.1. Squatting strugglesIf you can’t perform a simple bodyweight squat or even get up from a chair without pushing off, it could be a warning sign. “This is usually tested using a chair stand test or a sit-to-stand test and the inability to do this is associated with dementia risk because poor lower limb strength and mobility indicate early decline in neural circuits involved in both motor and cognitive function,” Dr Bing explained.2. Acting out dreamsEver kicked, shouted, or punched in your sleep? That might be more than restless dreaming. Dr Bing said, "If someone is frequently kicking screaming or punching their partners in bed, this can be seen in REM sleep behaviour disorder (RBD) and is a strong predictor of future dementia, especially synucleinopathies like Lewy body dementia and Parkinson's disease." This happens because in RBD there is early degeneration of brainstem structures that regulate REM sleep.”3. LonelinessSocial isolation doesn’t just hurt emotionally. According to Dr Bing: “This is associated with increased dementia risk due to chronic activation of stress pathways increased inflammation and reduced neurotrophic support, which leads to accelerated nerve degeneration. Loneliness is also linked to reduced grey matter volume and also altered BDNF expression, which can lead to cognitive decline.”4. Weak hand gripA firm handshake may actually say something about brain health. “This reflects overall physical frailty and is correlated with reduced brain volume and impaired executive function,” Dr Bing said.A wake-up call in 10 secondsStanding on one leg may sound like child’s play, but it could be one of the simplest brain health checks available. While no single test can diagnose dementia, these early markers could act as a wake-up call. If you find yourself struggling, it might be worth talking to your doctor—not just about your balance but about your brain.