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 damage to your liver.

These health hazards mirror the effects of drinking too much alcohol, 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.

The report’s author Dr Robert Lustig, a UCSF childhood obesity expert, said: “As long as the public thinks that sugar is just ‘empty calories’, we have no chance in solving this.”

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 the nation is already eating too much of this added sugar. Indeed, the 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 35 million 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 – people who are a normal weight could benefit from sugar reduction as well.

Dr Lustig 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.

Yet changing eating habits is not going to be easy. Dr Amelia Lake, a dietician at Durham University, points out that picking up food or drink that’s laden with sugar in a shop is easier than buying something healthier.

“Sugary foods are always going to be part of the diet, but should be a much smaller proportion of it,” she said. “It would be difficult to exclude them, but it’s all about proportion. If these sugary products are in your face all the time, it’s hard to resist.”

How to cut down on your intake NHS Choices says that for a healthy balanced diet, many people need to cut down on food and drink containing added sugar.

  • Instead of sugary fizzy drinks and juices, try water or unsweetened fruit juice.
  • Dilute fruit juice for children to further reduce sugar.
  • For fizzy drinks, dilute fruit juice with sparkling water.
  • Swap cakes or biscuits for a currant bun, scone or malt loaf.
  • If you take sugar in hot drinks, or add sugar to breakfast cereal, gradually reduce the amount until you cut it out completely.
  • Instead of jam or sugary preserves on toast, try sliced banana or low-fat cream cheese.
  • Check labels to pick foods with less added sugar, or go for low-sugar varieties.
  • Try halving the sugar used in recipes – it works for most things except jam, meringues and ice cream.
  • Choose tins of fruit in juice rather than syrup.
  • Choose wholegrain breakfast cereals, but not those coated with sugar or honey.