Is Fast Food Fat Food?

Many people have seen Morgan Spurlock’s Documentary Super Size Me, and many were convinced by his experience that fast food is inherently bad for you. What these people don’t realize is that Spurlock’s real problem is that he simply overate. Other people ate McDonald’s for a month straight and were skinnier and healthier after than before. Two good examples are Scott Caswell or James Painter. Even at McDonald’s it’s possibly to eat right.

But that’s not the whole story. Case studies are interesting, but rarely revealing or reliable enough to qualify as real science. That’s why I dug into the peer-reviewed literature in medical journals to find out all I could about fast food. I’ve condensed that down into some quick conclusions.

Continue reading...There are many problems with fast food, including “enormous portion size, high energy density, palatability, excessive amounts of refined starch and added sugars, high fat content, and low levels of dietary fiber.” The most important of those, at least in terms of weight gain, are the portion size, and energy density. I’ll focus on energy density first.

Energy density is simply how many calories are in a given volume of food. This is important because humans evolved eating things that have relatively low energy density, and as such our bodies are best equipped to deal with those foods. For example, if you ate enough apples to feel full and enough Big Macs to feel full, the Big Macs will give you much, much more energy, probably around 1,000 Calories more, which is half the daily Caloric needs.

This in and of itself actually isn’t a problem, it only becomes one when this energy isn’t used. The study by Ebbeling and colleagues found that while everyone eats far more fast food than required to satiate their energy needs, overweight people are much less likely to work it off. Why this is so is undetermined, but it points to the conclusion that burning the excess energy is the main concern with fast food, and that overweight people (for whatever reason) don’t do that as well as people of normal weight.

And this makes sense. People gain weight because they take in more energy than they use. So people need to be more careful with fast food because it has more energy per unit volume than we’ve evolved to deal with. People who don’t compensate gain weight, those who do compensate won’t gain anything.

Portion size is another problem, but one that’s spread across our entire culture. Portion sizes have increased on everything from bagels to fast food to candy bars, and we haven’t adjusted. For example, a standard bagel supplies the entire daily requirement for grain for someone on a 1,600 Calorie diet (2,000 is the recommended norm). This is significant for fast food, which we already know is energy dense. Eating a large portion of something with a high density and not burning off the Calories is a recipe for weight gain.

“Value Pricing”, where larger sizes are less per unit, is probably an important culprit for this trend, but there are doubtlessly others. Some studies suggest that eliminating value pricing is the easiest step we can make toward losing weight. But even then, it’s ultimately up to the consumer to decide what goes in their mouth.

The other thing to take into consideration is whether fast food is an aberration from a healthy diet, or typical of the diet. A study by Newby and colleagues found that diet correlates well with BMI, with diets high in fruit, vegetables, and whole grains being the best, and diets consisting of meats and starches were among the worst. But again, this just confirms what we already know, eating natural, unprocessed foods in a balanced diet is the best way to be healthy.

Where does fast food fit into that scheme? The surgeon general says that it can be eating as part of a healthy diet, but many might be skeptical of that. However, the evidence suggests that he’s right: as long as the energy is worked off, eating fast food is not bad. There might be long-term health problems because typical fast food lacks some vitamins and minerals, but every fast food chain now offers salads, which should supply the needed nutrients. The only fair conclusion is that fast food is not actually all that bad when proper balances used.

As always, the key to being healthy is eating right and exercising. We can indulge in high-calorie, “bad” fast food, as long as we balance it out. It might not be the conclusion Morgan Spurlock or the people suing McDonald’s for “making them fat” want to hear, but it really is simply up to the consumer to manage their own health.

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Sources:

• Boon, Gloria, et al. “National Summit on Obesity.” American Medial Association. October 2004. 19 May 2006.
  
  
• Bowman, Shanthy A, and Bryan T. Vinyard. “Fast Food Consumption of U.S. Adults: Impact on Energy and Nutrient Intakes and Overweight Status.” Journal of the American College of Nutrition 23.2 (2004): 163-168.
  
  
• Ebbeling, Cara B, et al. “Compensation for Energy Intake From Fast Food Among Overweight and Lean Adolescents.” Journal of the American Medical Association 291.23 (2004): 2828-2833.
  
  
• Freeland-Graves, Jeanne, and Susan Nitzke. “Total Diet Approach to Communicating Food and Nutrition Information.” Journal of the American Dietetic Association 102:100 (2002).
  
  
• Harnack, Lisa, and Simone French PhD. “Fattening up on fast food.” Journal of the American Dietetic Association 103.10 (2003): 1296-1297.
  
  
• Jacobs, David R. “Fast food and sedentary lifestyle: a combination that leads to obesity.” American Journal of Clinical Nutrition 83.2 (2006): 189-190.
  
  
• Newby, PK, et al. “Dietary patterns and changes in body mass index and waist circumference in adults.” American Journal of Clinical Nutrition 77.6 (2003): 1417-1425.
  
  
• Prentice, A. M, and S. A. Jebb. “Fast foods, energy density and obesity: a possible mechanistic link.” Obesity Reviews 4.4 (2003): 187.
  
  
• Pruitt, Julie D, et al. “Nutrition as a contributor and treatment option for overweight and obesity.” American Heart Journal 151.3 (2006): 628-632.
  
  
• Young, Lisa R, and Marion Nestle. “Expanding portion sizes in the US marketplace: Implications for nutrition counseling.” Journal of the American Dietetic Association 103.2 (2003): 231-234.