The 'silent killer' going undiagnosed in 4 out of 10 Brits - key symptoms to look out for

Over four out of ten adults in the UK are unaware about living with a silent killer condition that goes undiagnosed for many. A study conducted by the charity Blood Pressure UK found 43 per cent of the people do not know their blood pressure.

The charity took into consideration around 2,000 people between the age of 40 and 55 to carry out a “simple, quick check”. The study revealed that one in three individuals fail to monitor their blood pressure regularly, and just 11 percent knew that people over the age of 40 should have it checked at least annually. An estimated 4.2 million people in England are living with undiagnosed high blood pressure.

High blood pressure, often referred to as the "silent killer," is a serious health condition that can lead to life-threatening complications such as heart attacks, strokes, kidney disease, vision loss, and vascular dementia.

It exerts excessive strain on vital organs including the heart, blood vessels, brain, kidneys, and eyes, gradually causing damage that may go unnoticed due to its lack of clear symptoms. Because it rarely presents warning signs, regular monitoring is essential for early detection.

The most reliable way to check blood pressure is by using an inflatable cuff around the arm, which measures the pressure in the arteries. A healthy reading typically falls between 90/60mmHg and 120/80mmHg, and values outside this range may signal a need for medical attention or lifestyle changes.

Blood Pressure UK estimates that five million people have it but are unaware.

Dr Pauline Swift, chair of Blood Pressure UK, said: “These findings are deeply concerning. High blood pressure is a silent killer — it often has no symptoms, yet it’s responsible for more deaths than any other preventable condition in the UK.

“The fact that nearly half of UK adults don’t know their blood pressure reading is a wake-up call. We’re urging everyone, especially those over 40, to take a simple, quick blood pressure check at home, in a pharmacy, or with their GP.

“It could be the most important step they take for their long-term health.”

Phil Pyatt, the charity’s CEO, said: “We know there are around five million people in the UK living with undiagnosed high blood pressure — the ‘Missing Millions’ who are unknowingly at risk of heart attack, stroke, kidney disease and early death.

“That’s why Know Your Numbers! Week is so important. A quick check and one small lifestyle change — like cutting back on salt or walking more — could save your life. Don’t wait for symptoms. There usually aren’t any.”

The only way to find out if you have high blood pressure is to have a blood pressure check.

Occasionally, people with very high blood pressure have symptoms including:

• headaches
• blood shot eyes
• feeling sick or generally unwell