Does a spoonful of sugar help the flu take hold?

Courtesy of USA Today

When one of pediatrician Jim Sears' kids asks for a soda or other sweet treat, he sometimes asks them a question: "Is this a good time to be suppressing your immune system?" Sears, who is co-host of The Doctors TV show and a contributor to the popular AskDrSears parenting website, is a firm believer in a widespread idea: A big dose of sugar can immediately suppress your immune system and make you more vulnerable to colds, flu and other infections. So, at a time when people are especially keen to protect themselves from H1N1, or swine flu, it's worth asking: Is it true?

Can a few spoonfuls of sugar really help make you sick? Denver nutrition therapist Kate Pfeiffer has no doubt. "Limiting sugar should be the first line of defense against infectious disease," she says. She wrote a column for Examiner.com titled: "Worried about the Swine Flu? Avoid Sugar!" In it she cites a 1973 study, published in the American Journal of Clinical Nutrition. The same study is cited at AskDrSears.com and on many alternative-medicine sites. In the study, researchers at Loma Linda University gave volunteers 100 grams of sugar (20 teaspoons, roughly the amount in a liter of soda). The researchers then drew blood from the volunteers and mixed in some bacteria. They found that infection-fighting white blood cells from people who had just gorged on sugar gobbled up many fewer bacteria than those who had just fasted or eaten an unsweetened starch.

But that's not evidence that would convince most doctors, says Aaron Glatt, an infectious-disease specialist who is president and chief executive officer of New Island Hospital in Bethpage, N.Y. Glatt says he has heard of the sugar theory, but as far as he knows, there are no studies showing people who eat a lot of sugar actually get more cases of colds and flu. He says: "There are numerous other reasons people should be concerned about sugar intake," including the prevention and control of obesity and diabetes. But, he says, "there's no reason not to drink a glass of soda just because someone next to you is sniffling."

Robert Frenck, professor of pediatrics at Cincinnati Children's Hospital Medical Center and a spokesman for the American Academy of Pediatrics, agrees: "I have not found any (studies) that show sugar changes your resistance to infection."

Christine Gerbstadt, a registered dietitian and physician who is a spokeswoman for the American Dietetic Association, combed through hundreds of studies and came to the same conclusion. She even found a recent study that suggested a sugar surge might boost immunity — at least in mice forced to run on treadmills and fed various diets. But it's unlikely any one food is the key to a strong or weak immune system, she says. Instead, she says, "we can optimize the building blocks for immune system by eating a healthy, balanced diet." Sears says he agrees wholeheartedly that overall nutrition is more important than any one substance. But he still says there's something about a sugar overdose that makes people vulnerable. He says he expects to see some evidence soon — when his office fills up with sick kids after Halloween.

Bonnie - should it be a surprise that the ADA is refuting the sugar suppressing the immune system. Take a look at some of their main sponsors: http://www.eatright.org/cps/rde/xchg/ada/hs.xsl/home_10575_ENU_HTML.htm. Many of their sponsors sport a multitude of sugar-laden foodstuffs.