Taxing junk food may improve your health

Originally published in MedPage Today

by Kristina Fiore, MedPage Today Staff Writer

Taxing junk food may help reduce obesity and improve health, researchers have found.

Taxing junk food may improve your health Patients got significantly less of their energy (calories) from soda or pizza when there was a 10% increase in the price of either (P<0.001), Penny Gordon-Larsen, PhD, of the University of North Carolina at Chapel Hill, and colleagues reported in the March 8 issue of Archives of Internal Medicine.

“Policies aimed at altering the price of soda or … pizza may be effective mechanisms to steer U.S. adults toward a more healthful diet and help reduce long-term weight gain or insulin levels over time,” the researchers wrote.

Talk of a soda tax has sparked debate across the country, particularly in New York and Philadelphia, where such legislation is currently under consideration. However, not much research has been done to study how price changes would affect health outcomes.

So the researchers looked at data from 5,115 patients enrolled in the longitudinal Coronary Artery Risk Development in Young Adults (CARDIA) Study from 1985 to 2006.

During that time, the inflation-adjusted price of soda and pizza actually decreased, with the largest drop observed for soda, falling from $2.71 to $1.42 for a 2-liter bottle — a 48% decline.

In their analyses, the researchers found that changes in the price of soda and pizza were associated with changes in the probability of consuming those foods, as well as in the amounts consumed.

A 10% increase in the price of soda was associated with a 7.12% decrease in energy consumed from it, while the same increase in the price of pizza led to an 11.5% drop (P<0.001).

Price was also significantly associated with total energy intake, body weight, and HOMA-IR scores (which measure insulin resistance).

A $1.00 increase in soda prices, for example, was tied to a mean of 124 fewer total daily calories (P=0.001), which amounted to an average weight loss of 2.34 pounds (P=0.006), and a decline in HOMA-IR scores of 0.42 (P<0.001).

The researchers noted that similar trends were seen for pizza, adding that a $1.00 increase in the price of both soda and pizza together was associated with even greater changes in total energy intake, body weight, and insulin resistance.

“Our results provide stronger evidence to support the potential health benefits of taxing selected foods and beverages,” they wrote. “Similar taxation policies have proven a successful means of effectively reducing adult and teenage smoking.”

They calculated that an 18% tax junk food tax would result in a 56-calorie decline in total daily energy intake. At the population level, that would translate to about 5 pounds per patient per year, along with significant reductions in the risks of most obesity-related chronic diseases, they said.

Since their study looked at only a small number of foods, they called upon researchers to assess more in future studies.

In an accompanying editorial, Mitchell H. Katz, MD, and Rajiv Bhatia, MD, MPH, of the San Francisco Department of Public Health, wrote that taxing is “an appropriate method of correcting for health and other social costs not accounted for in the private market cost.”

However, they added, in addition to taxing unhealthy foods, policymakers should consider ways to reward healthy behaviors.

“Sadly, we are currently subsidizing the wrong things, including the production of corn, which makes the corn syrup in sweetened beverages so inexpensive,” they wrote. U.S. agricultural subsidies should instead “be used to make healthful foods such as locally grown vegetables, fruits, and whole grains less expensive.”

“In the end,” Katz and Bhatia concluded, “putting our money where out mouth is means aligning our economic incentives so that we always serve up the healthful choice.”

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  • IVF-MD

    Can I toss out a question here? Who are WE to judge that a 80 year lifespan, at a healthy 160 pounds, devoid of pizza and ice cream is absolutely superior for everyone as compared to a 60 year lifespan, at a unhealthy 190 pounds, full of an abundance of decadent gourmet delights?

    If a small cadre of people who enjoy telling other people what to do really really want for others to be healthier, that can be noble, but they are better off doing it via compassionate persuasion than by violence-enforced taxation. There is violence inherent in their proposed tactic because what if the fat person refuses to pay 10% extra for their soda? Are the bureaucrats just going to let it slide saying, “Well OK, we were just doing it for your own good, but if you don’t want to give us 10% more of your money, then you are free to choose.” :)

  • rezmed09

    I really would like a junk food tax, but… the devil’s in the details. Pizza? What about Calzone? What about a salad with fatty ranch dressing? What about breakfast “snacks”. In California Ho-Ho’s (my favorite) some how was able to be classified as a breakfast food.

    How about a different approach? Tax the glycemic index. Tax the trans/saturated fat amount. Or better yet, how about subsidizing fruits and vegetables more? We should do away with commodities and food stamps and replace them with “fruit stamps.”

  • BD

    I’m in favor of taxing junk food for a selfish reason… this would discourage ME from purchasing and consuming empty calories.

    In case you’re wondering, my BMI usually hovers around 21 (i.e., I’m far from obese). Regardless, I really don’t like how I feel after eating junk food or drinking soda, and I have an unhealthy, addictive response to potato chips: I can’t eat just one, and pass the onion dip, please. On the other hand, I’m also thrifty when it comes to buying food with minimal nutritional value, so…

    Bring on the taxes! This will no doubt inspire me to more consistently pack some fruit, pretzels or an energy bar and carry my water bottle when I leave the house. Of course, if enough people are so inspired, something else will be taxed. I just hope internet usage isn’t next. :-)

  • SarahW

    No taxing food – that’s bad enough…but the government is not in charge of my daily diet, long may it stay that way.

  • SarahW

    BD, I’m sorry you think you need a nanny. Why don’t you just decide to eat something else?

    • BD

      >>I’m sorry you think you need a nanny. Why don’t you just decide to eat something else?>>

      I’m sorry you misunderstood my somewhat dry sense of humor.

  • Red

    The best thing the government could do is to eliminate the subsidies on corn. Coke and Doritos anyone?

  • Paynehertz

    Since 90 percent of the processed food sold in the supermarket is so loaded with corn syrup as to qualify as “junk food” as well–not that that has anything to do with diabetes or obesity, perish the thought!–then perhaps the tax should be on all processed food. Of course, this is just another “poor tax” scam, punishing the poor for inability to afford healthier food, complete with lots of the requisite puritanical elitist sneering that invariably accompanies any discussion of obesity in America.

    I can’t think of a simpler and cheaper way to radically improve the nation’s health than banning corn syrup from most foods. Big Agra will fight it tooth and nail, but it will cost the country nothing to implement and will dramatically lower the rates of obesity and diabetes.

  • ninguem

    Pizza doesn’t have to be junk food, it just depends on how it’s made.

    Pizza came to the USA as a simple peasant food, the taste for it was brought over from Italy to the USA with WW-2 soldiers.

    If I make a Bruschetta, is it still junk food? What made it not junk? French bread slice instead of unleavened dough? Chopped tomato instead of pureed sauce? Basil sprig instead of mass-produced seasoning?

    Pizza, Bruschetta – Same ingredients, just made up differently.

  • chinocochino

    I don’t care what people eat as long as it affects me. That said, I don’t want to be sharing insurance with the many (majority?) of americans that stuff their faces with McDonalds and weird trans-fat derived food. Most people aren’t motivated enough to eat healthy and exercise. Please spare me the argument that vegetables and fruits are too expensive–I survive on 120 dollars a month for food while eating fish, fruit, and vegetables. In addition, I eat about 4,000 calories a day. (probably more,actually) Its a question of buying food on sale and cooking in bulk to save time.

  • chinocochino

    I don’t care what people eat as long as it *doesn’t affect* me

  • Trious

    I would believe this. If it costs more to buy bad foods, chances are I think twice before buying it

  • IVF-MD

    How about the tax be limited to you people who keep saying that you need taxation to prompt you to eat healthier, while the rest of us get to buy our food at tax-free stores with freedom from bureaucratic meddling haha :) Then we’d all be happy.

  • BD

    >>How about the tax be limited to you people who keep saying that you need taxation to prompt you to eat healthier>>

    So, you already make healthy choices?

    I do. I belong to a CSA, cook healthy meals with whole grains from scratch and never drink any kind of soda (I don’t like it). I don’t visit fast food restaurants, with the exception of the occasional latte from Dunkin Donuts (I don’t like donuts).

    It is true that every so often, probably once every month or two, I purchase and consume some potato chips. With onion dip. They’re delicious. So I’m not perfect. Oh well.

    >>the rest of us get to buy our food at tax-free stores with freedom from bureaucratic meddling>>

    If you eat more junk food than I do, well, I object to subsidizing the medical care you and your ilk tend to require as a result of your poor dietary choices. Treating cardiovascular disease, type II diabetes and the orthopedic issues that arise as a consequence of being overweight is expensive. It’s true that those who eat as I do can experience the same problems, but we are at much lower risk.

    Cigarettes, other tobacco products and alcohol are already taxed. Why not add a sin tax on junk food?

    I’d gladly pay a little extra for an occasional bag of crunchy, greasy, salty goodness.

    • IVF-MD

      I object to subsidizing the medical care you and your ilk tend to require as a result of your poor dietary choices

      So what makes more sense?
      1. Subsidize everyone’s health care and then control their lives including what they eat?
      2. Let people be free to choose their lifestyle but just don’t subsidize their healthcare?

      • BD

        >>1. Subsidize everyone’s health care and then control their lives including what they eat?
        2. Let people be free to choose their lifestyle but just don’t subsidize their healthcare?>>

        Such grand choices.

        How ’bout:

        3. Admit that if the cost of healthcare were equally borne by all citizens, regardless of risk factors, the vast majority of us would pay far more $$$ into the system (whether via taxes, insurance premiums, or both) than we would ever receive in “benefits”?

        In the meantime, no one is proposing holding a gun to your head, saying “no Cheez Doodles for you!”. Furthermore, if you, like me, are among the most highly educated and thus highly paid members of this society, I’m sure a Twinkie tax wouldn’t harm your bottom line appreciably. It might make that bunch of bananas in the produce department more attractive, though.

  • ninguem

    I’ve heard a few years ago, the Brits did a simple experiment. Statistically recorded height/weight of students in a school district. Then they didn’t tax, but simply removed, all the carbonated soda drinks in vending machines and cafeterias in the schools.

    Measure height/weight again over subsequent years, and weight went down.

    At least received wisdom. Does anyone know if that was really done, or just some medical urban myth?

  • BD

    >>Does anyone know if that was really done, or just some medical urban myth?>>

    Dunno, but soda is relatively high in calories. So is fruit juice (according to my sister’s pediatrician).

    It’s astonishing what one can learn when one reads food labels.

  • ninguem

    “…..soda is relatively high in calories. So is fruit juice…..”

    Yes, true. Personally, I tend to water down my fruit juice. Seltzer water is a nice trick. Sort of juice-sodapop.

    Fewer calories, and I’ve grown to like it that way.

  • IVF-MD

    The argument is not that the “government not do anything under any circumstance”. It’s that there should be nothing done via coercion backed by violence. There is a big difference.

    If a group of people want others to eat less junk food, they are free to do it by peaceful voluntary persuasion. For example, they may choose to pool their money and form a “healthy eating reward fund” and offer the money to others who avoid all hot dogs or whatever criteria they decide. The hot dog eaters can choose to take that reward/bribe/incentive whatever you call it and eat healthy or they can choose to live their own unhealthy lives in peace.

    What’s morally wrong is to force the hot dog eaters to pay an extortion fee just to exercise their innate God-given right to eat hot dogs. Of course by voluntary social contract, the healthy-eating-promoters are free to let the hot-dog-eaters be responsible for their own angioplasties.

    There was a time when people thought anti-slavery people had “nice ideas” but were nuts because it would never work in real life. Well look how far we’ve come today. Maybe not in my lifetime, but I hope there will be someday when civilization will evolve to live in a mutual peaceful voluntary society without violent coercion, once we have developed enough morally.

  • MS1

    The only reason that we have so much corn syrup in our diet is because of agricultural subsidies and tariffs on imported sugar. I think that at the very least we can start by not actively promoting the injection of corn syrup into our diet with these policies.

    Also, a tax on soda/junk food is no different from taxes currently levied on cigarettes and alcohol. One can choose not to drink or smoke and one can also choose not to eat junk food. There will exist a libertarian argument against the government doing anything in any circumstance, but a tax on things such as soda and other particularly unhealthy foods would not be significantly different from current taxes used by the government.

    The main problem would be deciding what qualifies as ‘junk food’. However, I think that a tax such as this would most likely create incentives for food corporations to create food products that are healthier and therefore avoid the ‘junk food’ tax.