To many, a tax on soda is a no-brainer in advancing the nation’s war on obesity. Advocates point to a number of studies in recent years that conclude that sugary drinks have a lot to do with why Americans are getting fatter.   But obese people tend to drink diet sodas, and therefore taxing soft drinks with added sugar or other sweeteners is not a good weapon in combating obesity, according to a new Northwestern University study.

An amendment to Illinois Senate Bill 396 would add a penny an ounce to the cost of most soft drinks with added sugar or sweeteners, including soda, sweet iced tea and coffee drinks. Related to the purpose of the tax, the legislation excludes artificially sweetened and diet sodas.

“After doing the analysis, it really turns out to be the case that obese people like diet soda so much more than regular soda that you can do whatever you want to the price,” said Ketan Patel, a fourth-year doctoral student in economics. “You’re not going to get that much change in obese people’s weight because they already drink diet soda.”

Patel, who recently presented his paper “The Effectiveness of Food Taxes at Affecting Consumption in the Obese: Evaluating Soda Taxes” at a U.S. Department of Agriculture conference on food policy in Washington, D.C., said he initially didn’t know if the diet soda preference was going to be a large factor in evaluating the effectiveness of the soda tax.

“The concern I had was that maybe obese people are less price sensitive,” Patel said. “So if obese people are less price sensitive, then raising the price through a tax will affect their behavior less.”

But that concern became irrelevant since diet drinks are not being considered in the proposed obesity tax.

Beyond its ineffectiveness in reducing obesity, such a tax also would punish consumers that are not overweight or obese, Patel said.

Is there a scenario in which increasing the tax would have an effect on weight? Patel said that could depend on whether people are at a stable weight or whether people are already eating too many calories and therefore their weight will continue to increase. If increasing weights are the status quo, then a tax could prevent people who are currently overweight or normal weight from becoming obese. More research needs to be done on this aspect, however, Patel said.

For this study, Patel used a large data set of sodas price and sales data with individual level data on demographic characteristics and body mass index (BMI) to estimate consumer preferences while allowing for substantial diversity in those preferences. After obtaining estimates of consumer preferences, Patel simulated how a tax would change the choices that consumers make and used the results of the simulation to estimate changes in weight using a weight change model from existing nutrition literature.

In the meantime, however, lawmakers say it does not look likely that the tax will be imposed anytime soon as there is little support for the measure after a recent income tax hike in Illinois.

by Hilary Hurd Anyaso,  law and social sciences editor. Northwestern U.



Taxing behavior with negative consequences has always been a popular revenue enhancer to the government. The real issue is how will those increased revenues be ultimately used. Far too often the original intended use of the monies becomes less of a priority due to budget shortfalls in other areas of government spending. By privatizing most government functions waste is reduced by operating an efficient enterprise with a profit motive rather than letting bureaucratic inefficiencies get in the way of the well intentioned purposes of government programs.

Good article. I'm glad to hear that the tax will not be increased on sodas. I personally don't think it would deter obese people from purchasing. And if this was passed, where would legislative stop? There are so many high calorie/fat foods that would be a contribution to overweight Americans.

I doubt it. Soda is only one part of the equation. Plus if people want it,, they will get it no matter what the tax.

I really hope this will help people to stop drinking too much soda and start to drink more water. Everything will be good for a healthier America.

I also believe that soda can make us fat. Recently I give up the habit of drinking all sorts of soft drinks and till now maintain the habits. I think tax is not a good solu

Tax for soda would be about like cigarettes...people are going to buy it no matter what...great article.

Great post ... very knowledgeable .... Soda should be ban as its making human being full of poison

The most interesting line in this article is that obese people tend to drink diet soda. Hmmm. Funny how diet soda has the perception of being healthy. Eat whatever you want but drink diet soda and you are healthy. Pretty ridiculous. But if they tax tobacco and other health damaging products than maybe soda and other junk should be included.

I've lost 140 pounds, and a lot of it was due to slashing big sugary drinks like 44 oz sodas from Mcdonalds. I support a soda tax.

What about an extra tax on the company that produces the diet soda. They are raking in a ton of profits on a product that is supposed to be "not as bad for you" so to speak. And instead it is adding to a major problem. Who knows - these companies may even know what the soda is doing to people and they just keep producing it and making money. Let's consider holding the companies responsible.

I don't even see the point in making a diet-anything. It's still a general rule of thumb for health buffs to keep ANY kind of snacking to a minimum. Besides, a regular Coke tastes better IMO. You might as well just drink that moderately than tick off your taste buds.

While soda and other products with high amounts of sugar or corn syrup may be contributing to a larger epidemic of obesity, a simple soda tax is not really a solution to the problem. At best, it attempts to attack a symptom of our cultural dietary habits, but this approach is reductive and short sighted, and of course, there is no real data to support its effectiveness.

definitely the new tax on soda will not stop people buying it. Peter

While I support doing whatever we can to combat obesity (I am formerly 343 lbs, and now 220 lbs), I think anything with added sugar should either be included in this or, rather the companies that produce the products should have to come up with the money, fees or taxes. My thinking behind it is this: added sugar is basically empty calories, and there are things other than soft drinks that have added sugar. No matter what weight I was, I have always had a love for Diet soda as opposed to regular soda, so I don't feel that the soda is the sole culprit. If we took the money from the 'added sugar tax' we could put it to use to lower the cost of natural foods like fruits and vegetables. If carrots, celery, lettuce, apples and bananas were always lower in cost, it might encourage more people to eat them. I know I would add more fresh fruits and veggies to my diet if they were cheaper...there are weeks that I have to pass up the produce section because the money just isn't there.

It is highly doubtful that tax will indeed decrease the demand of soda. Think of cigarettes and all the taxes associated with it. It wasn't the price increase that decreased smokers, but years of actual education on the health risks associated with it.

Why would one want to limit taxation to such a narrow sector of ingested foods and products? Why not tax obesity itself regardless of how attained? How about a per pound tax over and above the Army Weight Control Charts? That should be fair. We could even impose a surtax on obese children under the age of 16. Hell, the parents pay regardless so why not make life a bit more difficult.

I believe taxing isn't going to have a large influence. Due to the fact that consumers are going to buy the soda no matter what. But great article and content.

I believe that consumers will buy soda regardless of the tax. The American Demand for soda in my eyes out weight the tax on them. But Great Content.

Great information.i hope you will write another good post

It might be best to tax all sugars - sodas are not uniquely damaging. I have a particular interest in panic attacks, having been affected by swings of mood, and I've found that cutting down on all refined carbohydrates virtually eliminates the ups and downs caused by changes in my insulin levels. Life is calmer now, more active and thinner !

I dont think that taxing it will make a huge amount of different. I feel that one of the main reasons people buy these is because they are cheap compared to a healthy drink such as a smoothie!

This post make sense. People gonna buy soda even it gives no good into our body because its cheap compared to healthy drinks.

It is highly doubtful that tax will indeed decrease the demand of soda.

I'm not so sure a tax would work. I think it's a culture thing that needs changed. Take a look at the Japanese - their sodas are cheap, it's the choice the culture makes to not drink as much pop. Increasing the cost won't curb it, it will just be a tax on poor people.

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