The food industry is facing a backlash against high sugar content on the same scale as the one experienced by the tobacco industry following studies showing a link between smoking and lung cancer, experts are warning.
With growing public awareness of the debate surrounding sugar, obesity and diabetes, "a structural decline in sugar consumption" is on its way, according to a recent report by the Credit Suisse Research Institute.
Sales of cigarettes in the developed world have been in steady decline since the 1970s, after the link between smoking and diseases like lung cancer and emphysema was proven. The industry was also hit by a round of lawsuits, which resulted in four major tobacco industry players agreeing to pay out $365.5 billion to settle claims over health issues caused by smoking cigarettes. Allegations that the industry was aware of the link between lung cancer and smoking as early as the 1950s were key to the cases.
At the beginning of the obesity epidemic, it was received wisdom that lowering fat and calorie consumption would shrink waistlines. Yet as the number of low-fat products on the market has risen, so have obesity rates - worldwide obesity has nearly doubled since 1980, according to the World Health Organization (WHO).
With the rise of obesity comes increased rates of Type 2 diabetes, heart disease and a raft of other health problems, which in turn makes treating patients more expensive for governments and insurers, according to the WHO.
(Read more: Putting a price on weight loss)
Scientists are still divided over the true causes of obesity, but the view that it is partly caused by high fructose corn syrup (HFCS), which is present in the majority of foods produced in the developed world, is gaining traction. HFCS is a cheap form of corn syrup used in most processed foods, cereals, and soft drinks, which gained popularity after the price of imported sugar increased in the U.S. during the 1970s.
Alarm bells have been ringing in the scientific community for years over the widespread use of HFCS, led by Dr Robert Lustig, who specialises in treating obese children and has written a book called Fat Chance about obesity.
(Read more: Obesity officially becomes a disease)
Lustig's talk: Sugar: The Bitter Truth has had nearly 4 million views on YouTube. In it, he argues that fructose is a "poison" which helps the body retain fat and is partly responsible for the obesity epidemic.
Fructose essentially delays the feeling of being full by suppressing the action of a hormone called leptin, which leads to further food consumption, according to Lustig's studies.
"It makes your brain think you're starving and now what you have is a vicious cycle of consumption, disease and addiction," Lustig said.
Many low-fat products are high in sugar and sweeteners. Lustig highlighted the increase in consumption of soft drinks and fruit drinks as one of the most important factors associated with the rise of obesity.
"There is an urgent need for increased public awareness of the risks associated with high fructose consumption and greater efforts should be made to curb the supplementation of packaged foods with high fructose additives, " according to the National Institutes of Health, the U.S. government body.
(Read more: Global middle class hungers for U.S. fast food)
The scientific community is divided over whether the anti-fructose lobby is right, and the Food and Drug Administration says that it is "not aware of any evidence" that HFCS is worse than other similar sweeteners. WHO does not cite fructose as one of the causes of obesity.
The Corn Refiners' Association, the industry body for HFCS producers, which has lobbied to have the sweetener's name changed, said: "There is no scientific evidence showing high fructose corn syrup (HFCS) is to blame for obesity nor showing HFCS affects your feelings of fullness any differently than sugar or other sweeteners.
"Many studies around sweeteners tend to focus on subjects consuming pure fructose. In real world settings however, fructose and glucose are consumed together, which does aid in satiety. The bottom line when it comes to appetite and maintaining a healthy weight is balancing your total caloric intake with an active lifestyle."
Nonetheless, a regulatory backlash is beginning against HFCS in the U.S., with new laws at the state level in California and New York. While New York City Mayor Michael Bloomberg's efforts to ban large, non-diet sugary drinks may have foundered after it met with protests, it is emblematic of new awareness amongst lawmakers on both sides of the Atlantic.
(Read more: Is Bloomberg's soda ban unconstitutional?)
If HFCS is banned or its use is limited, the basic cost of producing food could also be hiked, affecting top lines across the food industry. So what can food and beverage makers do to avoid the trials and tribulations of the tobacco industry?
"It's not quite another tobacco story," Stefano Natella, co-head of securities research and analytics at Credit Suisse, told CNBC.
"With tobacco, there was medical research which proved a direct link to lung cancer. In this case, there is a contribution but the problem is that you can never prove causality to diabetes type 2 – you can't measure how much sugar people are eating."
The food industry will also find it easier to produce a fructose-free product than the tobacco industry did a nicotine-free cigarette.
Food giant Nestle reduced the overall sugar content of its products by 30 percent between 2001 and 2011, a spokesman for the company said.
Beverage companies like Coca-Cola and PepsiCo are likely to be at a bigger disadvantage than food manufacturers, on the grounds of both taste and the fact that many of the sweeteners used to lower calorie counts are high in HFCS, Natella argued. Aspartame, one of the sweeteners used in diet drinks including Diet Coke and Diet Pepsi, had its FDA approval suspended for years, and six appeals against the FDA's eventual decision to allow its sale in food by objectors. Coca-Cola, PepsiCo and Dr Pepper Snapple are three of the companies most at risk from a sea change in attitudes to fructose, according to Credit Suisse, with sweetener manufacturers Tate & Lyle and Ingredion not far behind.
"Because of the variety of offerings in the food industry, it will be easier to mask different flavors. The beverage industry is in a much more difficult position. If you look at the history of people launching new products, people react negatively," he said. "Your ideal solution is make the sweetener natural but with lower calories."
(Read more: How to sell less food for more money)
The launch of New Coke in the 1980s was a famous flop, and the company had to re-introduce the classic Coca-Cola formulation after three months. Sales have fallen in the U.S. for both Coke and Pepsi in recent years, but both companies have countered this with a growth in emerging market sales, and an increase in sales of other beverages.
"We have always listened and responded to our consumers changing demands," a spokesperson for Coca-Cola Great Britain said.
"We recognise that helping consumers to achieve healthy lifestyles, including reducing the calories they consume, is really important."
The company cited recent moves to lower calories and sugar content in its drinks.
(Read more: Apple leaves Coke flat)
Rival PepsiCo pointed to its "balanced beverage portfolio" - low- or zero-calorie beverages, healthy juices, and active hydration drinks accounted for nearly half of its sales volume in 2012.
"We offer low- or zero-calorie beverage options in all our key global markets, and we help our consumers around the world manage calories by offering smaller portion sizes and providing clear calorie labeling," a PepsiCo spokesperson said.
If the new innovations aren't successful with consumers, the future of the industry could prove to be bittersweet.
"The threat will cause companies to make their own interventions – ultimately they care about what volumes they sell," Natella said.