WEDNESDAY, Sept. 26 (HealthDay News) -- People with type 2 diabetes have a different balance of bacteria in their digestive system than do people without the disease, new research indicates.

Chinese researchers conducted what's known as a metagenome-wide association study on microbes found in the gut to determine how they might be different in people with type 2 diabetes. They identified more than 60,000 markers, or indicators, associated with type 2 diabetes. And, they found that people with type 2 diabetes had an abundance of potentially harmful bacteria, and a reduction in the amount of helpful microbes.

What's not clear, however, is whether these changes can cause type 2 diabetes, or if these changes occur because of type 2 diabetes. Still, the researchers suggest that these findings offer clues that might help develop new treatments.

"I think our study provides many targets for disease prevention and treatment through gut microbiotia in the near future," said study senior author Jun Wang, executive director of the Beijing Genomics Institute in Shenzhen, China.

Results of the study were published in the Sept. 26 online edition of Nature.

Type 2 diabetes is a metabolic disorder that causes the body to use insulin inefficiently. Insulin is a hormone that helps blood sugar enter the body's cells to be used as fuel. In type 2 diabetes, the body may not use insulin properly (called insulin resistance), or there may not be enough insulin, according to the American Diabetes Association.

Symptoms include frequent infections, cuts or sores that are slow to heal, blurred vision, fatigue, tingling or numbness in the hands and feet, unusual thirst, frequent urination, unexpected weight loss and extreme hunger, according to the diabetes association.

The cause of type 2 diabetes is unknown, but is believed to be a combination of genetic and environmental factors. Recent research has suggested that an imbalance in the microbes in the intestines may play a role in type 2 diabetes.

To see what effect, if any, intestinal bacteria might play in type 2 diabetes, Wang and his team analyzed the genetic make-up of the gut microbes from 345 Chinese adults, some with and some without type 2 diabetes.

They found that the natural balance of "intestinal flora" was different in people with type 2 diabetes than in those without the disease. They found 60,000 markers related to type 2 diabetes, and concluded that some of these markers could be used to indicate a risk of type 2 diabetes before the disease develops.

The researchers said there's still a question as to whether or not these changes actually cause type 2 diabetes, and they are working on new studies to try to answer that question, according to Wang.

Several doctors not involved with the study said it's way too soon to know if the Chinese research will lead to useful insights and treatments.

"There's no way right now that you can say there's a cause-and-effect relationship. It could be that the patients with diabetes were treated with drugs that changed their gut flora. Or maybe they ate differently? This is an interesting hypothesis -- that gut bugs could influence diseases states -- but it's far from proven," said Dr. Stuart Weinerman, associate chief of the division of endocrinology at North Shore University Hospital/Long Island Jewish Medical Center in New Hyde Park, N.Y.

Dr. Joel Zonszein, director of the Clinical Diabetes Center at Montefiore Medical Center in New York City, agreed that this is an interesting study. But, he added that he doesn't believe there is one single cause of type 2 diabetes, such as a change in intestinal bacteria.

"Type 2 diabetes is a complex disease. I think the intestinal flora could be contributing to the pathogenesis of type 2 diabetes. The type of food we eat, the antibiotics we take, the preservatives in food all have a role in altering the microbial environment in the body. Small changes in certain patients may have tremendous impact," he said.

More information

Learn more about type 2 diabetes and its causes from the U.S. National Library of Medicine.

MONDAY, Sept. 17 (HealthDay News) -- Obese people with type 2 diabetes who consume increased amounts of fructose -- a simple sugar -- may have high levels of uric acid and a reduction in liver energy stores, researchers say.

High uric acid, or hyperuricemia, is linked to lower levels of liver adenosine triphosphate (ATP), a compound involved in transferring energy between cells, scientists from Duke University Medical Center explained in a news release.

The researchers, who published their new report in the September issue of the journal Hepatology, noted that energy depletion in the liver could result in liver damage for those with the metabolic condition known as non-alcoholic fatty liver disease and in those at risk for the condition. They stressed that the public should be aware of these risks associated with a diet high in fructose.

"There is an alarming trend of increased rates of obesity, type 2 diabetes and [non-alcoholic fatty liver disease] in the U.S.," lead author Dr. Manal Abdelmalek said in the journal news release. "Given the concurrent rise in fructose consumption and metabolic diseases, we need to fully understand the impact of a high-fructose diet on liver function and liver disease."

Fructose is a simple sugar found in fruits and vegetables. It also is combined with glucose to manufacture high-fructose corn syrup, a sweetener in many packaged foods such as cereal and soda.

The researchers examined nearly 250 obese and diabetic adults participating in the Look AHEAD Study. The participants were asked to estimate the amount of fructose they consumed.

Liver ATP and uric acid levels also were measured in more than 100 patients who participated in a second study. Researchers measured the difference in liver ATP content between patients with low fructose consumption (less than 15 grams per day) and those with high fructose consumption (greater than 15 grams per day).

The study revealed that participants with high dietary fructose consumption had lower liver ATP levels when the study began and a more significant change in ATP after the fructose test. The researchers also noted that those with high uric acid levels had lower ATP stores following high fructose intake.

Based on their findings, the researchers suggested uric acid, which is produced by the breakdown of natural food substances known as purines, may serve as a marker for increased fructose consumption and low levels of liver ATP.

"High fructose consumption and elevated levels of uric acid are associated with more severe depletion of liver ATP," Abdelmalek said in the news release. "Our findings suggest that increased dietary fructose intake may impair liver 'energy balance.' Further research to define the clinical implications of these findings on metabolism and NAFLD is necessary."

Although the study found an association between a diet high in fructose and liver risks in certain people, it did not prove a cause-and-effect relationship.

More information

The American Heart Association has more about sugars and high-fructose corn syrup  .

WEDNESDAY, March 21 (HealthDay News) -- The costs of the obesity epidemic to the United States and the economic value of curbing it are not captured fully by current methods, according to a new report.

The problem is that estimates used by Congress when it looks at these issues project out only 10 years, while it may take much longer than that for complications of obesity, such as diabetes and heart disease, to manifest, the report authors say.

For example, "a person with diabetes is not going to go on dialysis right away. They're going to go on dialysis 10 to 12 years after their diagnosis," said Michael O'Grady, co-author of the report, released Wednesday by the Campaign to End Obesity.

A 25-year window for making policy decisions would be more appropriate when drafting policies aimed at curbing disease, he said at a Wednesday morning press conference.

By the same token, measures to prevent obesity can take 20 or more years, perhaps even generations, to show their promise, the report said. A wider time window would enable policy makers to assess the cost-effectiveness of preventive programs, the report noted.

"Interventions aimed at children will not have their full payoff until those children are adults," said Dr. James Marks, senior vice president and director of the Health Group at the Robert Wood Johnson Foundation, which funded the study.

Nor will the success of interventions aimed at pregnant women be seen for many years, noted the study's authors, speaking at the briefing.

O'Grady, citing current CDC figures, said more than one-third of U.S. adults are overweight, another one-third are obese and 6 percent are extremely obese.

"That's right around three-quarters of the population," said O'Grady, a senior fellow for health care research at the National Opinion Research Center at the University of Chicago and a principal with O'Grady Health Policy, LLC.

One estimate puts the annual cost of obesity at $147 billion, representing almost 10 percent of all medical expenses, the report said. But the Society of Actuaries -- which adds in lost productivity, employees on full disability and absenteeism -- puts the costs closer to $300 billion a year.

And at a minimum, the Congressional Budget Office predicts that per-person, obesity-related spending will increase an average of 3.6 percent a year, the report said.

The authors are asking those who make up budgets, including the Congressional Budget Office, to take into account a growing body of scientific literature on the toll of diabetes as well as hopeful interventions when they tally the price of obesity.

A window of 25 years will help policy makers arrive at more accurate long-term estimates, they said.

"Ten years is adequate for food stamps and aircraft carriers, but there are certain policy areas where we know the disease has a 20- to 25-year progression. You need the flexibility to go beyond 10 years," O'Grady said. "We probably want to modify the status quo of how we measure these things in order to capture the full value of that."

Marks said two of the greatest challenges the nation faces are restoring global economic competitiveness and the skyrocketing costs of medical care, which has become perhaps the biggest obstacle to long-term economic strength.

"Obesity lies right at the center of those challenges," he said. "The way Congress acts to score legislation, using only a 10-year horizon, misses a huge part of the value of preventive efforts."

The authors served in the George W. Bush administration. O'Grady was assistant secretary of Health and Human Services, and co-author James Capretta served as an associate director of the Office of Management and Budget.

More information

Visit the Campaign to End Obesity   for more on the new report and the issue.