US researchers and health advocates have called for heavier tax on sugary soft drinks in an effort to curb consumption and raise funds for new health programmes.

Writing in the New England Journal of Medicine, New York City health commissioner Dr Thomas Farley and academics from the Harvard School of Public Health and Yale University proposed an excise tax of 1% per fluid ounce for any beverages with added caloric sweeteners.

Their study found that, although 33 US states currently tax soft drinks and other sugary beverages, taxes have been too low to curb consumption.

"Because of the contribution of the consumption of sugar-sweetened beverages to obesity, as well as the health consequences that are independent of weight, the consumption of sugar-sweetened beverages generates excess health care costs," the authors said.

Obesity tax revenues should be earmarked for health care programmes, they added.

Earlier this year, US Senators proposed a federal tax rise on both sugary and alcoholic drinks as part of president Obama's health reform.