When New Year’s Day rolled around, many people resolved to lose weight in 2010.  How many of them are on track to be successful?  Every year, the majority of people making weight loss resolutions fail to achieve them.  The result of these failures is highlighted in a recent study by the Centers for Disease Control that estimated the body fat percentage of a typical American woman to be 40% and the typical American man at 28% based on a six year analysis of data.[i]  Although it varies somewhat by age, the optimal body fat for women is 18-22% and for men 15-18%.  Nearly double?  This is not good news.

Whatever the excuse for why a weight loss program fails, the core reason is that the person attempting to lose weight did not change their lifestyle.  Attempting a temporary diet is a sure path to failure, because the dieter is not committing to changing the negative actions that caused the unwanted weight gain.

Another problem with diets is that they aim for weight loss, not fat loss.  Too many of these diets are nutritionally unbalanced.  The body needs each class of nutrients in the right proportions: fats, carbohydrates, and proteins, in addition to vitamins, and minerals.  The typical American diet lacks sufficient protein and contains excessive amounts of highly processed carbohydrates and unhealthy fats.

“Crash diets,” the kind promoted in magazines with titles like “Lose 10 pounds by next week!” are even worse.  Most of the weight lost in these diets is water.  All body tissues are mostly water, so water weight loss is part of all diets.  By removing almost only water weight, however, you are not changing any of the risk factors associated with excess body fat.  Worse yet, most crash diets call for essentially starving yourself.  This sends signals to the body that you are going through a period of famine.  The body responds by increasing your fat stores when normal eating is resumed, to prepare for the next “famine.”  The end result, then, is exactly the opposite of what is intended.  Instead of becoming healthier and lighter, you add weight[ii].  In fact, women that have gone through multiple periods of weight loss and weight gain (referred to as weight cycling), store more fat in their abdomens[iii].  Abdominal (or visceral) fat is a risk factor for many negative health consequences including cardiovascular disease, diabetes and premature death.[iv]  Having a higher amount of abdominal fat is directly linked to higher levels of “bad” cholesterol (LDL) and lower levels of “good” cholesterol (HDL).  It is also linked to insulin resistance, and metabolic syndrome[v].

So the healthy way to weight loss is to change your approach to food.  Include more fruits and vegetables, lean protein, healthy fats and whole grains.  Tomorrow we’ll take a look at the impact of a group of chemicals that scientists have dubbed “obesegens”.

[i] Li C. Ford E. et al.  Estimates of body composition with dual-energy x-ray absorptiometry in adults.  Am J Clin Nutr 90: 1457-1465, 2009. First published October 7, 2009; doi:10.3945/ajcn.2009.28141

[ii] Kroke A. Liese AD. Schulz M. et al. Recent weight changes and weight cycling as predictors of subsequent two year weight change in a middle-aged cohort. Int J Obes Relat Metab Disord. 2002 Mar;26(3):403-9.

[iii] Rodin J. Radke-Sharpe N. Rebuffé-Scrive M. Greenwood MR. Weight cycling and fat distribution. Int J Obes. 1990 Apr;14(4):303-10.

[iv] Pischon T. Waist circumference predicts mortality better than BMI. European Prospective Investigation into Cancer and Nutrition (EPIC). New Eng J Med. Nov 2008.

[v] Anonymous. Abdominal fat and what to do about it. Harvard Women’s Health Watch. 2006 Dec;14(4)