Just recently, while seated in the top-level seats at a Utah Jazz basketball game, it was painfully obvious that the future health care system in the USA is going to be dramatically overburdened by a generation of obese adults, if it isn't happening already. Admittedly, to get to the top row of seats in the arena it was a tough climb up 19 rows of steep steps, however it is a sad commentary when one man, perhaps 45 years of age and visibly obese remarked that, "that's enough exercise for the entire week".
Actually it's not fair to single out North Americans, as even Hungarians, Danish, Russian, Turkish, and Dutch researchers are identifying obesity as a huge problem. All around the world scientists are attempting to find pharmaceutical and nutritional interventions to combat the problem of obesity. Even the Chinese are getting fat, likely due to the "McDonald's disease" (the introduction of fast food restaurants and a sedentary lifestyle into their culture). Type 2 diabetes, high blood pressure, and abnormal blood lipid levels are now common in Hong Kong Chinese and this is closely associated with the increase in obesity.
More importantly, is that these countries are also observing increased obesity incidence in their youth, so it's not just a reflection of the "American" culture, but rather the sedentary lifestyle seen across a generation, in combination with very poor nutritional choices. However, remember that there have been a number of reasons proposed as a cause of obesity (hormonal, genetic, societal, physiological, psychological, neurotransmitter), and of course some of these overlap. According to the World Health Organization, the prevalence of obesity has increased so rapidly in many populations that the changes cannot be attributed to changes in genetic inheritance alone.
* Americans (and many other modern countries) are suffering from a "fat" epidemic.
* 55% of American adults are overweight or obese (Women = 50.7% & men = 59.4%).
* More specifically, 22% of US adults are obese (Women = 25% & Men = 19%).
* The economic costs of obesity are staggering. Researchers estimate that the financial drain from obesity and physical inactivity is over $90 billion a year, representing 15% of the American national health care expenditure.
* Americans spend $33 billion per year on products and services to help them lose weight (this includes gym memberships, diet soda, low-cal foods, and dietary supplements).
* Dietary supplements sales were $16.8 billion in 2000. Ten years ago sales were only $3.3 billion. The fastest growing segment is diet aids.
* The United States spent $1.2 trillion on healthcare in 1999 and this will increase to $2.6 trillion by 2010, likely because prescription drugs costs will grow by 12.6% per year.
Both rich and poor North Americans have equal opportunity to become overweight in these days of $5 fast food feasts. Body fat is simply the storage of excess energy intake from a positive energy balance. Energy balance can be best expressed as the calories (energy) consumed in comparison to the energy (calories) you burn off each day. Food energy is measured as a calorie, and so is the work that you do during exercise. Therefore, this basic energy equation (calories in vs. calories out) determines whether you gain, lose, or maintain your weight.
You expend energy every minute of the day, although the final amount is obviously determined by your activity level, not to mention your muscle mass (more muscle results in more energy being expended at rest). Diet-induced thermogenesis (DIT) also contributes to energy expenditure and obese adults often show lowered DIT compared to lean adults. DIT is the amount of energy that your body expends during the digestion, absorption, and utilization of food energy.
Obese adults that have a low DIT have a more efficient utilization of calories and greater ease of fat accumulation. In less technical terms, this simply means that "naturally thin" individuals (also referred to as individuals with "fast metabolism") use up more energy during these processes and as a result have less energy to store as body fat.
Chronic overfeeding (regardless of whether it is carbohydrate or fat) is associated with obesity, insulin resistance, and elevated blood insulin levels. Insulin is an anabolic hormone with both good and bad connotations. Fortunately, it can prevent muscle breakdown after exercise and it helps the muscle store glycogen (a fuel for high intensity exercise), however it can also increase the storage of blood free fatty acids in fat cells. It also limits fat mobilization (the release of fat from fat cells to be used for energy production). So even if you are consuming a low-calorie diet but still consuming a diet that promotes high insulin levels (i.e. lots of high-glycemic carbohydrates), you may have difficulty losing body fat.
There is evidence that "high-glycemic" carbohydrates are best avoided by those seeking to lose weight. High-glycemic carbohydrates are refined foods such as processed cereals, cookies, pasta, white rice, cakes and other processed goods high in sugar. The term high-glycemic refers to the rapid increase in blood sugar that these foods cause after ingestion because they are rapidly absorbed. In a recent study in the American Journal of Clinical Nutrition (71: 901-907, 2000), researchers found that after only 6 days, subjects eating low-glycemic foods lost more body fat than subjects eating high-glycemic foods. Also, the group eating the low-glycemic foods had a higher metabolic rate and a lower rate of snacking on sugary foods.
From 1994-96 Americans consumed the equivalent of 82 grams of high-glycemic carbohydrates per day from added sweeteners, which was about 16% of total calories. Adolescents had the highest intake, about 20% of calories, with soft drinks accounting for a third (!) and table sugar, syrups and sweets, sweetened grains, and milk products providing the rest. That translates into almost 330 calories of sugar per day! Eliminate this from your diet and you have the potential to lose 1 pound of fat (generally considered to be 3500 calories) in 10 days.
While the prevalence of obesity continues to rise controversy remains as to the specific causes of this trend. What about the phenomenon of winter fat? Roberts et al. (2000) determined that the weight gain during the 6-week winter period from American Thanksgiving through New Year averaged only 0.8 lbs. However, weight gain was greater among individuals who were overweight or obese, and 14% gained more than 5 lbs over this time period. Among the entire population, weight gain during the 6-week holiday season explained 51% of annual weight gain.
So it appears that most weight gain does occur during the holiday period and by early March their was a recorded net weight gain of approximately 1-1.5 lbs (Robert et al., 2000). If you do that every year you can see how "the pounds creep up on you". In another study, Yanovski et al. (2000) found a similar trend and therefore American adults should expect to see a net weight gain (winter fat!). In conclusion, it looks like holiday weight gain really is the important contributor to the rising prevalence of obesity that many people often make it out to be, even though absolute values for weight gain in this study were less than anticipated.
Craig Ballantyne is a Certified Strength & Conditioning Specialist and writes for Men's Health, Men's Fitness, Maximum Fitness, Muscle and Fitness Hers, and Oxygen magazines. His trademarked Turbulence Training fat loss workouts have been featured multiple times in Mens Fitness and Maximum Fitness magazines, and have helped thousands of men and women around the world lose fat, gain muscle, and get lean in less than 45 minutes three times per week. For more information on the Turbulence Training workouts that will help you burn fat without long, slow cardio sessions or fancy equipment, visit one of the ads on this page or download one of the apps for your mobile as they're free.