The attack, launched by the Center for Consumer Freedom (CCF), comes in response to an admission by the Centre for Disease Control (CDC) that it was wrong to publish figures last year claiming 400,000 Americans die annually from obesity-related illness.
The CDC printed a correction in the Journal of the American Medical Association (JAMA) at the end of January, and has since rounded the figure down to 365,000. But the CCF said the whole study was based on poor science and should be publicly retracted.
In a letter to CDC director Dr. Julie Gerberding, the CCF said: "Using this erroneous study as support, you have personally terrified the public about obesity, at one point comparing it to the Black Death."
Calls for the CDC to publicly withdraw its study have now been echoed by an editorial in the Washington Times newspaper, citing CDC researchers who have since criticised the study's methodology and claimed they felt under political pressure to endorse it.
Last month, the results of an internal investigation by the CDC found that there were "fundamental problems centred around both the data and the methodology" in the study.
However, CDC spokesperson Karen Hunter told www.BakeryAndSnacks.com that "despite the correction [to the figure] it does not change the overall conclusion, which is that deaths from poor nutrition combined with physical inactivity are second only to tobacco in terms of preventable deaths in the US".
Hunter conceded that the CDC's internal review led "us to realise that there are a number of steps we can take to improve the agency's scientific clearance process". But she re-iterated that obesity was a major risk factor for the leading killers in the US: heart disease, type 2 diabetes and certain cancers. The CDC estimates that 65 per cent of American adults are either overweight or obese.
Dan Mindus, senior CCF analyst, said people in the US had been "systematically misled about the size and scope of the obesity problem", and that many statistics, were compiled by researchers receiving funding from pharmaceutical companies making anti-obesity drugs.
The CCF, which is due to publish a report on the lobbying activities of drug companies trying to get clearance for their anti-obesity pills, did not deny there was an obesity issue in the US, but spokesperson Mike Burita said that "people should not be scared into thinking that if they have a hamburger or even a whole milk drink that they are going to die".
Burita and Mindus, who rejected further government regulation such as current proposals for an obesity tax on foods high in fat and salt, added that it was wrong to victimise certain foods in this way. People should be given accurate information to help them take more personal responsibility for the foods they eat, they said.
There are signs that top food industry players are also becoming tired with criticisms directed at so-called unhealthy foods. US cereal and snack giant Kellogg said last week at an analyst conference that the obesity issue should not be about 'bad foods', but more to do with calorie intake and exercise.
The company's chief financial officer, David Mackay, said there was not much wrong with many foods available and that the obesity debate had become a bit too emotional.
CCF analyst Mindus said that, in any case, market forces were already pushing food companies to change existing products and innovate to tap into a growing healthy eating trend among consumers.
For example, Kellogg has expanded its Special K brand to include Red Berries and Vanilla Almond varieties in the last few years, and the firm's main rival, General Mills, recently announced it would make all its Big G cereals with whole grains.