Study that shows overweight have reduced mortality risks than previously thought may mislead the public, experts say. With major incidence of obesity in Emirates experts fear US analysis may give heavier residents excuse not to become healthier.
UAE health fears over report on weight risks
ABU DHABI // A US study suggesting people classified as overweight have a reduced risk of early death has UAE experts concerned that residents may use it as an excuse not to strive for better health.
They say this is of particular concern in the Emirates, where World Health Organisation figures show 67 per cent of men and 72 per cent of women are overweight or obese.
"People are getting the wrong message," said Dr Tarek Saleh, a consultant gastroenterologist at Medcare Hospital in Dubai.
"They will see this [report] as a chance to eat whatever they want and before we know it, an already existing problem will become worse."
The report was led by a researcher from the US Centres for Disease Control and Prevention (CDC) and published in the Journal of the American Medical Association this month.
It analysed 97 published studies and looked at the body-mass index (BMI) - calculated using weight and height - of almost 3 million people between the ages of 40 and 70, and compared their mortality risks.
The report found that the obese had a higher risk of death compared with those of normal weight. But it also found those classified as overweight had a 6 per cent lower risk of death than those of normal weight.
Dr Saleh said factors such as body composition should also be taken into account: "We don't know how much of their weight is fat and how much is muscle.
"Also, many of them could have already started seeking treatment."
The results of the analysis did not surprise Dr Salah Gariballa, professor and chair of the department of internal medicine at UAE University.
Dr Gariballa said the report should be used as another opportunity to demonstrate why BMI is not sufficient as a health indicator by itself.
It is not uncommon for overweight people to lead healthier lifestylesthat lessen the risks of excessive weight, he said.
"For example, the health of an overweight person who is exercising and eating the right kind of food will be better than a normal-weight person who does not exercise and eats junk food," Dr Gariballa said.
Also important is where the fat is concentrated. The most dangerous fat is visceral fat, which surrounds organs and secretes toxic substances, Dr Gariballa said.
Subcutaneous fat, just under the skin, is less dangerous. Because of this, many argue that waist circumference is a better predictor of health risks, particularly heart attack.
This was demonstrated in the 2004 Interheart study published in TheLancet magazine, which looked at more than 15,000 heart attack cases and found abdominal obesity was a stronger risk factor than BMI.
"This is true in the Middle East where many people, especially men, have a normal BMI but increased waist circumference," Dr Gariballa said.
UAE University has just finished an 18-month study on how antioxidants found in fruits and vegetables can fight inflammation caused by visceral fat. It looked at 100 diabetics from Tawam Hospital's diabetes centre.
Among those, 30 were overweight, 60 were obese and 92 had a waist circumference that classified them at increased or high health risk.
Patients were given antioxidant tablets over three months and the results showed a positive effect in fighting inflammation caused by abdominal fat.
Study researchers say possible explanations for the reduced mortality risk includes earlier presentation of heavier patients and the greater likelihood of them receiving the correct medical treatment.
Another explanation the researchers put forward was that some body fat can have a beneficial effect.
Kiram Tbayli, a nutritionist at the weight-loss company VLCC, agrees that fat can play protective role.
"Fat holds vitamins A, used for vision; B, for calcium; E, an antioxidant; and K for blood circulation," Ms Tbayli said. "When you get sick, you need these vitamins to strengthen your body's immunity. As people grow older, they need more fat to store these vitamins."
On average, an adult male should have 12 per cent body fat and women between 20 and 22 per cent, Ms Tbayli said. Regardless of age, exceeding 28 per cent body fat is considered dangerous.
"This is why in addition to BMI, an assessment of the fat, muscle and water composition is essential," she said. "Not everything can be determined from BMI alone."