More than 300 studies will be presented during the annual conference, organized by the Obesity Society, a US scientific association created 25 years ago to study the phenomenon.
Between 64 percent to 66 percent of adults in the United States are overweight, of whom 60 million are obese with the epidemic on the rise.
More than a billion adults worldwide are overweight, according to the World Health Organization (WHO), and there are at least 300 million obese people on the planet.
In Europe, Britain leads with a 23 percent obesity rate, followed by Germany at 12 percent and Italy at eight percent, according to a study published at the end of 2006 by the Organization for Economic Cooperation and Development (OECD).
In France, 5.9 million people are obese, of which 2.3 million are nine years old.
In China, the obesity rate can reach 20 percent in some cities, according to the WHO.
Over the four-day conference, scientists will review genetic research and how modifying genes can affect weight, the retention of body fat and appetite.
A major element of the conference will be devoted to sociological and behavioral studies as lifestyle, diet and a lack of exercise are the primary causes of the epidemic. Pediatric obesity is also a top priority, with 20 percent of American children deemed obese -- a figure that has tripled in 40 years.
A person is considered obese if his body mass index (BMI), calculated by dividing weight by the square of his height, is more than 30. A patient is considered overweight if the BMI is between 25 and 30.
Obesity, which can reduce life span by five to eight years, is linked to increased risk of diabetes, hypertension, arthritis and cancer.
An increase in the occurrence of type two diabetes over the past 20 years in the United States is due to the rise in obesity, according to The Obesity Society.
Being overweight is also blamed for doubling the risk of kidney cancer and breast cancer for post-menopausal women.
Death rates in the United States due to bad diet combined with a lack of exercise represent 16.6 percent of all deaths, almost equal to the toll from smoking.
The conference is being held in a region hard-hit by the epidemic. Poorer US southern states have particularly high rates of obesity.
In Mississippi, which has one of the highest poverty rates in the United States, nearly every third adult -- 30.6 percent -- was obese, and slightly more said they engaged in no physical activity, said a report released in August.
The rate of adult obesity more than doubled in percentage terms in the past 25 years across the United States, growing from 15 percent in 1978-80 to 32 percent in 2003-04, said the Trust for America's Health (TFAH) in its annual "F as in Fat" report.
In the same period, childhood obesity increased more than three-fold.
The report urged "new, grand scale changes" across the country to stop the obesity epidemic from undermining the country's productivity.
"US economic competitiveness is hurting as our workforce becomes less healthy and productive. Obesity-related health care costs are draining dollars from the bottom line of businesses," it said.