Sugars added to processed foods and fizzy drinks poses a greater threat to the heart than salt, it has been claimed.
Doctors have called for dietary guidelines to focus more on the dangers of sugar, and less on salt.
A new study warns added sugars - rather than than added salt - are likely to have a greater role in raising blood pressure, as well as triggering heart disease and stroke.
In the fight to curb the prevalence of heart disease, the experts warn the dangers, particularly linked to fructose, must be highlighted.
Heart disease is the number one cause of premature death in the developed world.
And high blood pressure is its most important risk factor, accounting for almost 350,000 deaths in the US in 2009 and costing more than $50 billion each year.
Dietary advice to help lower high blood pressure has historically focused on cutting salt intake.
But the potential benefits of this approach are 'debatable', the authors of the new study said.
They said the average reduction in blood pressure as a result of restricting salt intake, tends to be relatively small.
Some evidence suggests that 3 to 6g of salt each day may be optimal for health - in fact, anything less than 6g is actually harmful.
Most salt in a person's diet comes from processed foods, which also happen to be a rich source of added sugars, the scientists argue.
'Sugar may be much more meaningfully related to blood pressure than sodium, as suggested by a greater magnitude of effect with dietary manipulation,' the study found.
'Compelling evidence from basic science, population studies, and clinical trials implicates sugars, and particularly the monosaccharide fructose, as playing a major role in the development of hypertension (high blood pressure).
'Moreover, evidence suggests that sugars in general, and fructose in particular, may contribute to overall cardiovascular risk through a variety of mechanisms.'
The researchers point the finger at high fructose corn syrup, which is the most frequently used sweetener in processed foods, particularly fruit-flavoured and fizzy drinks.
The study states: 'Worldwide, sugar sweetened beverage consumption has been implicated in 180,000 deaths a year.
Around 300 years ago, people only consumed a few pounds of sugar a year, they add, whereas current estimates suggest that average consumption in the U.S. is between 77 and 152lbs a year - equivalent to 24 to 47 teaspoons a day.
The evidence suggests that people whose dietary intake of added sugars adds up to at least a quarter of their total daily calories have almost triple the cardiovascular disease risk of those who consume less than 10 per cent.
And a daily intake of more than 74g of fructose is associated with a 30 per cent greater risk of blood pressure above 140/90 mm Hg and a 77 per cent increased risk of blood pressure above 160/100 mm Hg.
Most of the salt in the diet comes from bread, processed meat, pickled foods and salt added during food preparation and at the table
A high fructose diet has also been linked to an unfavourable blood fat profile, higher fasting blood insulin levels, and a doubling in the risk of metabolic syndrome.
Some dietary guidelines do include recommendations about daily intake of added sugars, but are not stringent enough, nor do they make specific recommendations about fructose, say the authors. And it's high time they did.
Of particular concern, they say, is that UK and U.S. teenagers may be consuming added sugars up to 16 times the recommended limit.
They emphasise that naturally- occurring sugars found in fruit and vegetables are not harmful to health. Eating fruit and vegetables is almost certainly beneficial.
'Just as most dietary sodium does not come from the salt shaker, most dietary sugar does not come from the sugar bowl.
Reducing consumption of added sugars by limiting processed foods containing it, made by corporations, would be a good place to start,' said the authors at the Mid America Heart Institute in Kansas City, Missouri.
And they go on to warn: 'The evidence is clear that even moderate doses of added sugar for short durations may cause substantial harm.'
Professor of cardiovascular medicine, Francesco Cappuccio, from the University of Warwick said high-sugar diets can contribute 'substantially' to cardiovascular disease.
But he warned placing too great an emphasis on reducing sugar, and not salt, is 'disingenuous'.
'Both should be targeted at population level for an effective approach to cardiovascular prevention,' he said.
Heart disease is the number one cause of premature death in the developed world.And high blood pressure is its most important risk factor, accounting for almost 350,000 deaths in the US in 2009 and costing more than $50 billion each year
'Unlike sugar, salt is not a nutrient but a chemical added to food in recent evolutionary time.
'Our bodies need no more than a tenth of the salt we currently eat.'
He warned there is 'absolutely no evidence' to support the authors' claims that lowering salt levels in processed foods could spark an increase in the consumption of starches and sugars.
'This shift in attention from salt to sugar is scientifically unnecessary and unsupported, and it reminds me of a well-rehearsed tactic used by industry and pseudoscience to divert public attention.
'It is inappropriate in a scientific publication.'
He added: 'We must stop this false argument about reducing either salt or sugar.
'Both must be reduced if we are to meet the UN targets of a reduction of cardiovascular disease of 25 per cent by 2025.'
Professor emeritus of nutrition and dietics at King's College London, Tom Sanders, echoed Professor Cappuccio's thoughts.
He said the effects of added sugars are 'exaggerated' in the study.
'Cutting salt intake and losing weight will lower blood pressure, but the evidence for a direct effect of added sugar is tenuous,' he said.
'Most of the salt in the diet comes from bread, processed meat, pickled foods and salt added during food preparation and at the table.
'Salt intake has fallen in the UK as manufacturers have reduced the amount of salt added to food.
'This has also been accompanied by a fall in blood pressure.
'Added sugar intake is derived mainly from sugar-sweetened beverages, confectionery, cereal products (cakes and biscuits).
'As far as I am aware there is no evidence to show that blood pressure is lowered when sugar-sweetened beverages are replaced by artificial sweeteners.
'To add to the Christmas cheer, alcohol definitely increases blood pressure and is probably a bigger cause for concern.'
Gaynor Bussell, dietitian and public health nutritionist, added that the study is not based on original work, 'nor has the evidence presented been balanced to include all evidence on the causes of hypertension'.
'It's not just sugar or salt that need addressing but also issues such as total calorie intake, fibre, fats and vitamin and mineral intake also,' she said.
The study was published in the journal Open Heart.
But experts have warned both sugar and salt levels must be tackled together to reduce deaths from cardiovascular disease
