Parkinson’s disease affects around 153,000 people in the UK
10:32, 05 Feb 2026Updated 10:56, 05 Feb 2026
It’s a lesser-known symptom of Parkinson’s(Image: Westend61 via Getty Images)
Parkinson’s disease manifests through numerous symptoms, more than 40 in total, including the characteristic tremor affecting the arms and hands. The order and development of these symptoms vary among the roughly 153,000 people across the UK living with this incurable neurological condition.
The majority of those diagnosed with Parkinson’s are aged over 50, though 1 per cent of patients are younger. While the three main symptoms primarily affect physical mobility, there’s one less obvious warning sign that can appear years ahead of the others.
The NHS identifies the main indicators of Parkinson’s as
tremor – typically starts in the hand or arm and is more likely to occur when the limb is relaxed and restingmuscle stiffness or tension (rigidity) – this can make it difficult to move around and make facial expressions, and can result in painful muscle cramps (dystonia)slowness of movement (bradykinesia) – physical movements are much slower than normal, which can result in a distinctive slow, shuffling walk with small steps, and can make everyday tasks difficult
The disease also brings a range of psychological symptoms, including anxiety, depression and difficulties with memory. For some individuals, one of the first indicators of Parkinson’s can be a loss of smell, known as anosmia.
The NHS has pointed out that this symptom “sometimes occurs several years before other symptoms develop”, including those affecting movement. According to Parkinson’s UK, as many as 95% of people living with the condition experience some level of reduced or lost sense of smell.
While it may be regarded as a “hidden” symptom, the consequences for those unable to smell their food can be far-reaching. The charity said: “Loss of smell can affect people in different ways.
“We rely on our sense of smell to taste food, so reduced smell can lead to weight loss or weight gain. It can also affect your mood, relationships and overall quality of life. In addition, loss of smell can affect your safety – for example, being unable to smell food burning.
“It does not respond to Parkinson’s medication, so is unlikely to get better even with this treatment.”
Other Parkinson’s symptoms, as outlined by the NHS, include:
Balance issues – increasing the likelihood of falls and injuriesNerve pain – resulting in unpleasant sensations such as burning, coldness or numbnessExcessive saliva production (drooling)Urination problems – including frequent night-time urination or unintentional urination (urinary incontinence)ConstipationSleep disorders (insomnia) – leading to excessive daytime sleepinessSwallowing difficulties (dysphagia) – potentially causing malnutrition and dehydrationSexual problems – including inability to achieve or maintain an erection (erectile dysfunction), or challenges with sexual arousal and orgasm (sexual dysfunction)Dizziness, blurred vision or fainting when transitioning from a sitting or lying position to standing – due to a sudden drop in blood pressureExcessive sweating (hyperhidrosis)