We all know that obese children tend to be inactive. This leads to the “obvious” conclusion that the solution to childhood obesity is simply more exercise. But what if that conclusion is totally wrong?
There is no mistaking that obesity and lack of physical activity are linked. But which comes first? The answer appears to be obesity (1). A study published online in the Archives of Disease in Childhood followed young children over a four-year period carefully measuring their physical activity with accelerometers to measure physical activity for seven consecutive days as well as their percentage of body fat using DEXA scans. What they found was that physical inactivity was not related to the increased accumulation of body fat, rather they found that increased body fat was the cause of decreasing physical activity. This is also the situation with adults (2-5).
So why do so many researchers believe that inactivity leads to fatness? Because it just has to be the answer. This belief persists in spite of numerous studies that demonstrate that increased physical activity has little impact on reducing childhood obesity (6). This is a classic case of don't confuse me with the facts, since in my heart I know I am right.
This is not to say that exercise has no benefits in obese children. In fact, the same authors had published an earlier study indicating that while intense exercise had little impact on fat loss, there is a significant benefit in reducing insulin resistance (7).
The implications of this study in children are immense. In essence, increasing public expenditures to increase physical activity will not address the childhood obesity epidemic no matter how much money you throw at the problem. Instead you have to focus on reducing calorie intake. However, this decrease in calorie consumption is not going to be accomplished by increased willpower, but by increasing satiety (lack of hunger) in obese children.
As I pointed out in my most recent book, “Toxic Fat,” if you want to increase satiety, you must reduce cellular inflammation in the brain (8). That is best accomplished by a combination of an anti-inflammatory diet coupled with high-dose fish oil.
Of course, as an alternative, you could always consider gastric bypass surgery.
- Metcalf BS, Hosking J, Jeffery AN, Voss LD, Henley W, and Wilkin TJ. “Fatness leads to inactivity, but inactivity does not lead to fatness.” Arch Dis Chil doi:10.1136/adc.2009.175927.
- Bak H, Petersen L, and Sorensen TI. “Physical activity in relation to development and maintenance of obesity in men with and without juvenile onset obesity.” Int J Obes Relate Metabl Disord 28: 99-104 (2004).
- Petersen L, Schnorhr, and Sorensen TI. “Longitudinal study of the long-term relation between physical activity and obesity in adults.” Int J Obes Relate Metabl Disord 28: 105-112 (2004).
- Mortensen LH, Siegler Ic, Barefoot JC, Gronbaek M, and Sorensen TI. “Prospective associations between sedentary lifestyle and BMI in midlife.” Obesity 14: 1462-1471 (2006).
- Ekelund U, Brage S, Besson H, Sharp S, and Wareham NJ. “Time spent being sedentary and weight gain in healthy adults.” Am J Clin Nutr 88: 612-617 (2008).
- Wareham NJ, van Sluijs EM, and Ekelund U. “Physical activity and obesity prevention: a review of the current evidence.” Proc Nutr Soc 64: 229-247 (2005).
- Metcalf BS, Voss LD, Hosking J, Jeffery AN, and Wilkin TJ. “Physical activity at the government-recommended level and obesity-related outcomes.” Arch Dis Child93: 772-777 (2008).
- Sears B. “Toxic Fat”. Thomas Nelson. Nashville, TN (2008).