Morgan Spurlock gained 25 pounds and suffered physically and emotionally after eating exclusively at McDonald's for just one month in his excellent documentary Super Size Me .
But that's not the reason "minimize fast food" is the rallying cry of almost all serious health and weight-loss advocates.
Spurlock's personal experiment makes for good entertainment, but personal stories aren't scientific proof, and can also lead to the wrong conclusion. There are, in fact, a few well- publicized stories of people losing weight on a McDonald's regimen (read carefully, though: what these unusual customers ate was a low-calorie diet, consisting of salads without the dressing and apples without the caramel).
The case against fast-food
From a nutritional point of view, if we were to invent the worst diet ever-with an ingredient list designed solely for unhealthy weight gain and cardiovascular and metabolic morbidity-we'd be hard pressed to imagine one worse than the typical fast-food regimen: Highly processed, lots of saturated fats, hydrogenated fats and refined sugar, salt by the teaspoons, very little fiber, very few vegetables and fruit, and many additives driving the "great taste" that keeps us coming back for more.
But the proof of un-health is not just in the ingredient list.
There's a growing body of evidence pointing at fast-food as a major contributor to obesity and disease. I'll mention just a few studies.
A prospective study in the prestigious scientific journal Lancet followed more than 3,000 young adults for 15 years, and showed that those who ate at fast-food restaurants more than twice a week had gained an extra ten pounds and had twice the risk of insulin resistance (a risk factor for type 2 diabetes) compared to those that ate fast-food less than once a week.
A study in the Journal of the American Dietetic Association showed that adults eating at fast-food restaurants consume 205 more calories per day than those who don't eat out.
To this growing body of proof a new study in the American Journal of Clinical Nutrition shows for the first time a connection between fast-food and the risk of type 2 diabetes.
The study followed more than 44,000 African American women aged 30-69 years for 10 years, evaluating by questionnaires every two years their medical history, weight, exercise, smoking, alcohol use, diet and other variables.
The researchers found:
• 2,873 women (6.5 percent!) developed type 2 diabetes during the 10 year follow-up.
• Eating frequent restaurant meals of burgers and fried chicken was associated with type 2 diabetes. After adjusting for age, family history of diabetes, TV watching, exercise and education, women who ate burgers more than twice a week had an almost 60 percent higher risk of developing diabetes compared to those that consumed no burgers for the past year. The increased risk for fried chicken was even higher-85 percent!
• Burgers and fried chicken probably affect diabetes mostly through body fat. Indeed, women in the study who consumed lots of restaurant meals had higher rates of obesity, and when controlling for Body Mass Index (or BMI), the correlation between the burgers and fried chicken and diabetes was still present but lower.
The authors discuss:"In the present study, participants who reported frequent consumption of food from restaurants also had higher energy and fat intakes and drank more sugar-sweetened soda. Portion sizes tend to be larger in restaurant meals than in meals eaten at home. Large portion sizes can lead to overconsumption of calories, thereby leading to weight gain and obesity. The energy density of restaurant foods such as burgers, fried chicken, and French fries is very high, which can lead to "passive overconsumption," the tendency of humans to consume a similar bulk of food with little reference to its energy density, which in turn can cause obesity. Fried foods also contain large amounts of partially hydrogenated oils, which may lead to insulin resistance."
The worst thing about fast-food
A few facts about fast-food that probably will surprise no one:• One in four Americans visits a fast-food restaurant daily.
• Almost half of American meals are eaten outside the home and half of these are fast-food meals.
• Fast-food meals are calorically dense and come in large portions.
• Fast-food is so heavily advertized that most kids can recognize McDonald's before they know how to speak.
But the worst thing about fast-food, in my opinion, is that it's so cheap!
Many families resort to fast-food because it's the cheapest way to feed an American family.
Fast-food restaurants are especially abundant in poor and minority neighborhoods . In fact, in many low-income neighborhoods, cheap fast-food joints are the only dine-out option -a practical, convenient and inexpensive option for busy people who work hard, have little time on their hands, and can't afford healthier options. Poverty is associated with obesity -at least in the US-and as long as fast-food is cheaper than making a simple, healthy meal at home, it will be very hard to get even motivated people to find the ingredients and the time to do so regularly.
Fast-food may be cheap in the short term but it's very expensive in the long run-obesity and diabetes cost a fortune.
And that's a real shame!
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