New York Mayor Michael Bloomberg has had, what became known as his Soda Ban, approved by the New York City board of health. The ban will limit the size that sugary soda drinks can be sold at to 16 ounces, or 473ml. Far from being an eccentricity of New York, however, similar attempts to reduce citizens' soda consumption are being considered in other parts of the world.

At the forthcoming UK Liberal Democrat conference, a tax on soda drinks will be proposed. Predictably the reason given was that they wish to promote a "healthier and more sustainable diet" through taxation. In same way that the Bloomberg soda ban is justified on the grounds of an obesity epidemic and public health crisis, the Lib Dems try to justify their illiberal policy on the grounds that they are simply acting as the benevolent guardians of citizens' health.

But the idea that sugary soda drinks are the cause of any "obesity epidemic" is questionable. In the US, for instance, as Reason Magazine has pointed out, "soda consumption per capita has remained steady over the past two decades as obesity numbers have continued to rise". This is similar in the UK. According to the British Soft Drinks Association: "while the incidence of obesity has increased in recent years, the consumption of calories from soft drinks has not increased and makes up only two per cent of the average diet".

The real issue, however, is not whether Coke's making people fat, but whether or not the state should be involved in how much soda you consume at what price. Policies such as these, which aim to alter people's lifestyles and personal consumption habits, are often framed as being an attempt to address a "public health crisis" or simply to improve "public health" in general.

But the only concern of "public health", should be when there is a direct risk of infectious disease spreading, an outbreak of something that poses harm to the public. Obesity is not contagious, and only poses a health risk to the individual who eats or drinks in excessive quantities, making it a private issue, not public. It has no direct bearing upon the wider public.

People should be free to consume soda in whatever quantity they wish, for whatever price stores, cinemas, and restaurants sell it at. Do people really want Michael Bloomberg deciding which size of soda you can have, or the Liberal Democrats trying to limit how much soda you can have through hitting our pockets?

Parents often decide for their children how much Coke, Pepsi or Fanta they can have, limiting the amount the child can consume, as we assume the adult is able to judge better than the child what the right amount of soda to drink is. While this may be the case, it is wrong for politicians to assume that they can assert a similar parental stamp of authority upon adult citizens and try to regulate our fizzy drink consumption.

The public are viewed as children, unable to decide for themselves what to drink and accept responsibility for their actions. Benevolent politicians must make decisions for us. Patriarch Bloomberg is there to ensure the infantilised public don't hurt themselves.

It's time they stopped frothing over our soda consumption and put a lid on it.

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