Distribution of Fat is Key

28/10/05 Some kinds of excess fat are worse than others. Until very recently, all overweight or obese people were considered to be at high risk for developing type 2 diabetes and high blood pressure which can lead to stroke, heart attack, and kidney damage.

Now, based on new insights, the medical community has a more differentiated view of obesity. It is not so much the Body Mass Index (BMI) that is the decisive factor, but rather where on the body the excess fat is distributed. Particularly dangerous is stoutness around the waist and abdomen, which used to be described with the euphemism “portliness” and was considered a sign of prosperity. Doctors refer to this as “abdominal obesity”. People with this form of overweight are especially prone to develop secondary diseases of obesity early on.

This is one of the newest findings that was presented at the 4th International Symposium on Obesity and Hypertension at the Max Delbrück Center for Molecular Medicine (MDC) Berlin-Buch. The symposium from October 27 – 29, 2005, in which 200 experts from Europe, North and South America and Asia participate, is organized by Professor Arya Sharma (McMaster University, Hamilton, Ontario, Canada) and Professor Friedrich Luft (Franz Volhard Clinic, Charité University Medical School Berlin/Helios Clinics Berlin-Buch and the MDC).

Researchers already established years ago that fat cells produce a multitude of substances which directly damage the cardiovascular system and the kidneys. Recently, they discovered that the fat cells of the abdominal tissue are especially active metabolically and are, therefore, especially dangerous. They produce hormones and messenger substances (adipokines) that greatly contribute to the development of hypertension and metabolic disorders, such as type 2 diabetes and elevated blood lipid levels. Doctors use the collective term “metabolic syndrome” when referring to these diseases.

By contrast, the Body Mass Index (BMI), which is calculated by dividing the body weight in kilograms by height in meters squared, says nothing about fat distribution. According to the World Health Organization (WHO), a person with a BMI of more than 25 kg/m² is considered overweight; whereas a person with a BMI of 30 kg/m² or more is considered obese. For example, a man who is 1.8 m tall and a weight of 81 kg has a BMI of 25 kg/m²; with a weight of 97 kg, his BMI would be over 30 kg/m². “The BMI remains the standard for determining whether someone is really too fat. However, doctors should pay attention to fat distribution as well,” Professor Sharma emphasized at the symposium in Berlin.

WHO: A Billion People Overweight – Europe Catches Up with the US
Overweight and obesity have become a worldwide problem over the past years, affecting not only the population of rich industrial countries but also those living in so-called developing and threshold countries as well. In such countries, abundance and hunger often co-exist. According to UN statistics, 6.5 million people died of hunger and associated secondary diseases in 2005 alone. By contrast, the World Health Organization estimates that worldwide a billion people are overweight and more than 300 million are obese. In Germany, 16 million people are too heavy which corresponds to 20 percent of the population. In fact, according to a 2002 international health survey, 75 percent of 25 year old German men are considered to be too fat. In this respect, they were only surpassed by like-aged Greek men, who topped the European chart at 78 percent. These two countries, together with Finland, Malta, Slovakia, the Czech Republic and Cyprus, even surpass the US as far as weight is concerned where 67 percent of the male population is considered to be too fat. The European Union (EU) estimates that between two and eight percent of the medical costs in the EU are spent for the treatment of overweight and obesity. In the spring of this year, the EU therefore launched an action platform to meet this challenge.

Shortened Life Expectancy
Scientists and doctors fear that overweight and obesity are threatening to shorten the dramatically increased life expectancy that has evolved over the last decades as a result of a sufficient food supply, among other factors. The increasingly urban lifestyle combined with insufficient exercise and sedentary lifestyle, an excess in overall food consumption, as well as an excess of consumption of high fat foods has led to the situation that people no longer work off their excess pounds. According to the WHO, around 250,000 people die every year in Europe alone from cardiovascular diseases as a consequence of being overweight and worldwide two to five million people die due to these factors.

High Blood Pressure and “Adult Onset Diabetes” Already in Children
Scientists and doctors observe with concern that even children and adolescents are increasingly overweight and that they suffer from ”adult onset diseases” early in life such as high blood pressure and even type 2 diabetes. The WHO assumes that worldwide 18 to 22 million children under five years of age are too fat. In Europe, one in five children is considered to be too fat and every year more than 400,000 overweight schoolchildren join these ranks. According to the International Obesity Task Force, the curve is steepest for children in England and Poland. Of the estimated 14 million European children who are overweight, three million are considered obese.

It is to be feared that these children are not only less healthy than their parents but that they also will have a shorter life expectancy, as Professor Jan Olshansky from the School for Public Health at the University of Illinois in Chicago warned recently in the New England Journal of Medicine. Indeed, studies from Iran, Croatia, and Poland that were presented at the symposium in Berlin show that overweight or obese children and adolescents already suffer from hypertension and type 2 diabetes.

According to a study at the University of Hamedan, Iran, overweight children have a 50 percent higher risk of suffering from high blood pressure than other children of the same age with normal weight. The doctors examined more than 1,000 school children aged six to eleven years. Doctors in Croatia, who performed medical check-ups on almost 800 children in Zagreb and Koprivnica, arrived at a similar conclusion, as did their colleagues in Poland. They are therefore demanding better education, starting at an early age, to teach children healthy nutrition.

Losing Weight – Easier Said Than Done
Lose weight and, most important, get rid of abdominal fat – that is what doctors recommend. It is the most effective way to reduce blood pressure and the risk for secondary diseases. But most patients do not succeed in losing weight and keeping it off. In a short time, most of the patients regain the pounds that took them such an effort to loose. Professor Sharma defends the patients: “It is too simple to make the patients alone responsible for this lack of success. Genetic factors play a role in the regulation of bodyweight, as do the fat cells themselves. Frequently, too, medications for blood pressure and diabetes make losing weight more difficult.”