The Heart Foundation is joining calls for a crackdown on the amount of sugar we're consuming.

Dentists are leading a charge for change with a call for a 20 percent tax on soft drinks to help reduce tooth decay, obesity and diabetes.

They also want sugary drinks out of schools, day care centres and council venues.

Heart Foundation food and nutrition manager Dave Monro said sugar is causing more harm than tooth cavities.

"What we're seeing is a strengthening body of evidence showing the link between high sugar intakes and risk factors for heart disease, so things like increasing body weight, blood pressure and cholesterol levels."