WPVI-TV Philadelphia
Overeating, genetics, and lack of exercise usually get the blame. But one doctor says for some people, it all begins with an insect bite.
Pat Keller-Berrett: "I'd put on something like 30 pounds that I could not lose."
Pat Keller-Berrett first noticed the trouble losing weight after a bout with Lyme Disease 8 years ago. It worsened after she got Lyme Disease again.
Pat Keller-Berrett/Oxford, Pennsylvania: "I couldn't lose more than a few pounds, no matter what I did."
By early 2003, she weighed over 240 pounds.
Keller: "I just basically gave up, and said - Ok, I'm going to be a 240-pound woman for the rest of my life."
During her battle with Lyme Disease, Keller went to see Dr. Ritchie Shoemaker, a Maryland physician studying the tick-borne ailment.
Dr. Shoemaker noticed Keller had high levels of leptin, a hormone that regulates how the body stores fat. He suggested an unconventional approach - restricting some foods in her diet, and taking cholestyramine, an old cholesterol-lowering drug.
Keller: "The first week I lost 7 pounds."
Eighteen months later, the pounds are still dropping off.
Keller: "I've gone down something like 5 sizes."
Dr. Shoemaker says he sees a lot of Lyme Disease patients with weight problems.
Dr. Shoemaker: "This is an illness that makes people tired, in pain, and fat."
Dr. Shoemaker believes that when a person is bitten by a tick, the tiny organisms that cause Lyme Disease unleash toxins. In many people, these toxins disrupt the body's ability to handle leptin, which is produced by fat cells. Instead of burning fat, these people store it, adding more and more weight. Dr. Shoemaker says the toxins remain, long after antibiotics wipe out Lyme Disease.
Dr. Shoemaker: "Cholestyramine, a very poorly tolerated, but very old-fashioned cholesterol medication, will bind to Lyme toxin."
He says once the toxins are out of the body, a Lyme patient can lose weight again. Penelope Pattenden says she's shed 20 pounds since trying Dr. Shoemaker's regimen.
Penelope Pattenden/St. Michael's, Maryland: "The weight came off quite rapidly. I was quite surprised."
Shoemaker's eating plan restricts foods high in amylose, a form of sugar. Pat and her husband don't eat wheat, potatoes, or refined sugars, but do eat a lot of fruits, vegetables, and dairy products, like cheese.
Kory: "We've got swiss cheese, jack cheese..."
So what do other physicians think? Dr. Rob Danoff of Frankford Health System says there's no science to support the Lyme toxin theory. He says these patients lose weight because they're cutting out certain sugars and starches. Plus, the drug cholestyramine is notorious for upsetting stomachs.
Dr. Rob Danoff/Frankford Health System: "You really wouldn't feel like eating. Not only that, cholestyramine can block some fat absorption."
Pat says, whatever the reason for her new shape- she's happy to have gone from this to this.
Keller: "I really like the way I'm eating, I like how I'm feeling."