They argue that high sugar levels affect a key area of the brain, which causes the heart rate to quicken and blood pressure to rise. The scientists from New York and Kansas also highlight a recent study of 8,670 French adults which found no link between salt and high blood pressure.
For years, people have been urged to slash their salt intake. Experts say it increases the risk of strokes by a quarter and it has been blamed on 3 million deaths worldwide annually.
But in an article in the American Journal of Cardiology, researchers, led by Dr. James DiNicolantonio, said: "It is sugar not the salt that may be the actual causative factor for high blood pressure.
"This notion is supported by meta analyses of randomised control trials (large-scale studies) suggesting that sugar is more strongly related to blood pressure in humans than sodium.
"Encouraging consumers to hold the sugar, not the salt, may be the better dietary strategy to achieve blood pressure control."
This research is further evidence of the health risks posed by eating too much sugar.
The American researchers believe that high sugar levels affect a key area of the brain called the hypothalamus, which causes the heart rate to quicken and blood pressure to rise.
They also think it may cause our bodies to produce more insulin, a hormone, which may also speed up the heart rate.
Dr DiNicolantonio, a heart disease research scientist at Saint Luke’s Mid America Heart Institute in Kansas City, also contradicts experts who claim reducing salt consumptions will lower levels of obesity and heart disease.
"We argue the opposite, a reduction in salt intake may lead to an increased intake in processed foods (and added sugars) and, thereby, increase the risk of diabetes, obesity, and cardiovascular disease," he said.
The reasons are complicated, but it is thought that low salt levels increase the amount of certain fats in the blood.
Dr Aseem Malhotra, a cardiologist and science director of Action on Sugar, a campaign group, said the public health risk posed by sugar had been underestimated.
"We know that sugar does not provide any nutrients and there is growing evidence it is an independent risk factor for many diseases," he stressed.
But Professor Graham McGregor, an expert in cardiovascular medicine at Queen Mary, the University of London, said the evidence blaming sugar rather than salt for high blood pressure was ‘incredibly weak.’
He said that research spanning several decades had shown a strong link between salt and high blood pressure.