Weight: A 'Setting of Complex Interlocking Systems'
This is the season when millions of us resolve to lose weight. Statistically speaking, weight loss is the most common New Year’s resolution, surpassing vows to do good deeds, spend time with family and find a better job. Researchers say it’s also the resolution most commonly broken.
The Harvard Medical School newsletter Healthbeat stresses we need both diet and exercise, and it urges us to keep math in mind. One pound of body fat stores some 3,500 calories, the letter says, and walking or jogging uses only about 100 calories a mile. It’s discouraging to think you’d have to walk an extra 35 miles lose one pound. But if you eat 250 fewer calories and walk for 30 minutes every day, you could lose about a pound in a week.
All sorts of apps are available to measure food intake and calorie burn. Scientific Reports Nature identifies a new tool—artificial intelligence. The popular app Noom is one of the biggest to turn to AI, and it is described in a Fast Company story by Michael Grothaus. An analysis of the results of 35,921 users from 2012 to 2014 found 77.9% of participants reported a decrease in body weight and nearly 80% said they kept the weight off for more than nine months. The app uses AI to analyze a user’s food intake and exercise data and suggest personalized diets, fitness regimes, and individualized tips on nutrition and health. But Noom President Artem Petakov told Fast Company that mathematical calculations have to be paired with motivation, and that comes with a human coach. (Personalized coaching programs start at about $45 a month.)
Forget will power, Petakov advises, it’s about behavior change, and he asserts behavior change can be learned, just like math or a foreign language. You can learn what triggered bad eating habits, he says, and learn to replace bad habits with better behaviors. Of course an empathetic and knowledgeable coach helps.
But don’t think it will be easy. A story by Gina Kolata in the New York Times Science of Fat series stresses that it’s simplistic to think there are only a few key places to intervene in the tangled web of controls that set a person’s weight. Researchers studying obese people who had bariatric surgery found there are multiple interacting mechanisms influencing weight, many of which are still not well understood. Dr. Lee Kaplan, an obesity researcher at Massachusetts General, told The Times that bariatric surgery, which only changes the digestive tract, immediately alters more than 5,000 of the 22,000 genes in the human body. After surgery, he said, there are also changes in hormones, neurons, the white blood cells in the immune system, and in the gut microbiome, the thousands of strains of bacteria in the intestinal tract.
Weight and its management need to be viewed as an “entire setting of complex interlocking system” where a whole network of activity responds to environment as well as genes, Dr. Kaplan says. He explains that means there are whole classes of signals coming from the gut and going to the brain and that they interact to control hunger, satiety, how quickly calories are burned, and how much fat is stored on the body. To make the science of weight and obesity even harder to penetrate, these systems can vary significantly from one individual to another.