Now, she's back on target, without a fitness tracking device, losing weight gradually, eating the right number of calories for her specific metabolism, she says, as it varies day-to-day, even if the number of steps she takes may be consistent.
A Fitbit spokeswoman said the company makes "the most consistently accurate activity trackers on the market," even outperforming heart rate straps and treadmills that calculate calorie burn. "While there may be a small difference of a few calories or steps between tests, ultimately the success of our products comes from empowering users to accurately see their overall health and fitness trends over time," she said.
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Jessica Reed, 38, a poet in Danville, Indiana, had a similar experience to Mulholland when she first got her wristband. On her blog, she called her mysterious weight gain "The Case of the Fitbit Defying Metabolism."
In the first few months she had the Fitbit, Reed was dieting and gained a few pounds, she explained, although she had been consuming fewer calories than she burned according to the device. "I speculate that my weight fluctuations correlate with my greater sense of well-being more closely than exercise habits," she emailed NBC News.
Experts are unsurprised that some fitness band wearers feel frustrated after they spend $100 on a fitness device and see the scale move in the wrong direction. Sustained weight loss, they say, often involves a lot more than just counting calories. Your overall "well-being," as Reed puts it, can, in fact, stump your fitness tracker.
"I see people using wristbands, tracking calories, and sometimes the weight just doesn't come off and they even gain a little with a Fitbit or Fuelband," said Madison, Wisconsin nutritionist and registered dietitian Margaret Wertheim, author of "Breaking the Sugar Habit: Practical Ways to Cut the Sugar, Lose the Weight, and Regain Your Health."
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