According to Blood Pressure UK, this could have dangerous consequences, such as increased likelihood of heart attack, heart failure, stroke and kidney disease.
Many people make lifestyle changes, such as losing weight or making their diet healthier, in order to lower it.
As well as reducing fat and eating more fruit and vegetables, many sufferers are encouraged to reduce their sugar consumption too – and often they will replace it with artificial sweeteners in drinks such as tea and coffee.
However, a new study has revealed that these low-calorie replacements, such as aspartame, sucralose and stevia, may have the opposite effect.
The research published in the Canadian Medical Association Journal has linked them to high blood pressure in return, as well as long-term weight gain and increased risk of obesity, diabetes and heart disease.
This is particularly worrying since consumption of artificial sweeteners is on the rise.
Indeed, sales of diet soft drinks have increased in recent years with full-sugar drinks making up just 38 per cent of the market.
However, the new research has revealed that artificial sweeteners may have a negative effect on metabolism, gut bacteria and appetite.
The study authors looked at 400,000 people for an average of ten years.
They found no consistent effect of artificial sweeteners on weight loss, despite this being a major selling point – in fact they tended to make people gain weight.
Dr. Ryan Zarychanski, study author from the University of Manitoba, said: “Despite the fact that millions of individuals routinely consume artificial sweeteners, relatively few patients have been included in clinical trials of these products.
“We found that data from clinical trials do not clearly support the intended benefits of artificial sweeteners for weight management.”
The findings come after a study published in April in the journal Stroke revealed an association between them and risk of stroke or dementia.
Dr. Meghan Azad, study author University of Manitoba, said: “Caution is warranted until the long-term health effects of artificial sweeteners are fully characterized.
“Given the widespread and increasing use of artificial sweeteners, and the current epidemic of obesity and related diseases, more research is needed to determine the long-term risks and benefits of these products.”
Their future research is to involve looking at how pregnant women’s artificial sweetener consumption may influence weight gain, metabolism and gut bacteria in their infants.