If you take sugar with your tea or put it on breakfast cereal, think on -- you may be ingesting a poison.
A new report claims sugar is a toxin and not just because of those empty calories that cause weight gain.
Scientists from the University of California, San Francisco (UCSF), who took a new look at the mounting scientific evidence on sugar, say that at the levels consumed by most people, sugar can change metabolic rates, raise blood pressure, critically alter the signalling of hormones and causes significant damage to your liver.
These health hazards mirror the effects of drinking too much alcohol (distilled sugar), and the scientists suggest that measures used to reduce alcohol and tobacco consumption, such as taxation and controlled access, might be useful in helping to reduce sugar consumption too.
"As long as the public thinks that sugar is just 'empty calories', we have no chance in solving this," warns the report's lead author Dr Robert Lustig, a UCSF childhood obesity expert.
Sugar is a carbohydrate that's found naturally in most foods, but is also added to many foods such as sweets, cakes and some fizzy and juice drinks.
Studies suggest people are already eating too much of this added sugar. Indeed, the UK's Department of Health's National Diet and Nutrition Survey up to 2010 found that, on average, all children and adults exceeded the recommended amount of added sugar in their diets.
Sugar is viewed by some as a key cause of the obesity pandemic, contributing to 35m deaths annually worldwide from non-communicable diseases such as diabetes, heart disease and cancer.
But it's not just the obese who may be at risk from sugar's toxicity, says Lustig, pointing out that normal weight people could benefit from sugar reduction as well.
He insists that while there are good calories and bad calories, good fats and bad fats, "sugar is toxic beyond its calories" when it's consumed to excess and that virtually every country in the world is now over the "toxic threshold".
Yet changing eating habits is not going to be easy, experts admit.
Study co-author Laura Schmidt, a professor of health policy at UCSF, stresses: "We're not talking prohibition, we're not advocating a major imposition of the government into people's lives.
"We're talking about gentle ways to make sugar consumption slightly less convenient, thereby moving people away from the concentrated dose. What we want is to actually increase people's choices by making foods that aren't loaded with sugar comparatively easier and cheaper to get."
Lustig and his co-authors also say that policies similar to those used to reduce alcohol and tobacco consumption, such as taxation and controlled access, plus tightening licensing requirements on vending machines and snack bars that sell high-sugar products in schools and workplaces, could help reduce sugar consumption.
However, Dr Mary Harrington of Sugar Nutrition UK, the research and information organisation funded by the UK's sugar manufacturers, stresses the UCSF report contains no new evidence.
She points out that expert committees, including respected bodies such as the World Health Organisation and the European Food Safety Authority, have not linked sugar with any non-communicable diseases.
"All major expert reports in recent years have agreed that sugar is not a significant cause of obesity, diabetes, coronary heart disease, or cancer," she says. "The simple conclusion is that you can eat sugar as part of a healthy balanced diet. No foods should be considered as good or bad, as they all have an important role to play."
Dr Amelia Lake, a dietician and public health nutritionist at Durham University, points out that picking up food or drink that's laden with sugar in a shop is much easier than buying something healthier.
"Sugar and sugary foods are always going to be part of the diet, but should be a much smaller proportion of it," she says. "It would be difficult to exclude them, and we wouldn't want to do that, but it's all about proportion. If these sugary products are in your face all the time, it's hard to resist."