Losing weight and keeping it off is challenging, but not impossible. Just ask the men and women on the National Weight Control Registry, an ongoing research study of adults who have lost at least 30 pounds and maintained it for a year or more.
But with obesity starting younger and younger, health experts realize that weight loss efforts and lifestyle changes for children and teens must start sooner, and need to be tailored to that age group to be effective. That's why researchers from the Miriam Hospital and the Warren Alpert Medical School of Brown University are starting the Adolescent Weight Control Registry, led by Rena Wing, director of the Weight Control and Diabetes Research Center at the Miriam Hospital, and Elissa Jelalian, associate professor of psychiatry and human behavior at Brown Medical School.
"We're doing it with the idea that we could develop better interventions for teens," says Jelalian. "We would also like to track kids over time to see how they do through transitions, such as from school to independence."
Through questionnaires and surveys, adult registry founders Wing and James O. Hill, director of the Center for Human Nutrition, have discovered similarities among successful losers, such as being faithful to regular exercise and diligent about portion control.
But teens lose weight differently from adults, Jelalian says, for many reasons: Teens and parents can initiate efforts; teens are learning to navigate through peer pressure and social situations; they don't always have access to gyms or fitness classes; and they're not always in control of what's served at meals.
The study is currently seeking participants ages 14 to 20 from around the country. Requirements are less stringent than for adults -- teens must have kept off at least 10 pounds for a year or more, and fulfill other conditions.
"I think when you get down to diet and activity," says Jelalian, "inevitably these kids will have somehow cut back on eating and upped their activity. But I think there are lots of ways of getting to that point."
Salad is a staple in the diets of people trying to lose weight. But make sure your lettuce is doused with some vinegar. A new study suggests vinegar is good for your health and may even help burn fat.
Researchers in Japan fed laboratory mice a high-fat diet and gave them acetic acid -- the main component of vinegar. Those mice gained 10% less body fat compared with mice who weren't given acetic acid.
Vinegar has long been used in folk medicine, and other studies suggest it may have an impact on blood pressure, blood sugar levels and fat accumulation. The new study, from scientists at the Central Research Institute, Mizkan Group Corp., in Japan, suggests that acetic acid fights fat by turning on genes for fatty acid oxidation enzymes. These genes release proteins that help break down fat.
If those low-carb diets are too meat-reliant -- or if you're worried about your LDL cholesterol levels -- consider the Eco-Atkins. It's similar to the traditional Atkins diet, but minus the animal products. Yep -- vegetarian.
All that meat in the typical low-carb, high-protein diet still makes some doctors leery, as it turns out. So although Atkins-like diets have been found to reduce insulin resistance and raise HDL, or good, cholesterol, the diets cause some concern because they haven't done much for LDL, or bad, cholesterol levels. At the same time, doctors have been hard-pressed to deny such diets' effectiveness for weight loss, at least in the short term.
So researchers in a new study decided to replace the animal proteins in a low-carb, high-protein diet with vegetable proteins.
In a study of 47 overweight people, researchers at St. Michael's Hospital in Canada put half of the participants on a variation of the Atkins diet (i.e. the Eco-Atkins) and some on a more traditional vegetarian regimen.
Like its forebear, the Eco-Atkins diet was low-carb, but the specifics vary dramatically. In the newer version:
* 31% of calories came from vegetable protein (in order of reliance: gluten, soy, fruits and vegetables, nuts and cereals).
* 43% of calories came from fats (again, in order of reliance: nuts, vegetable oils, soy products, avocado, cereals, fruits and vegetables and seitan products).
* 26% of the calories came from carbs.
The other diet was a high-carbohydrate, low-fat, lacto-ovo diet (dairy and eggs allowed). Carbs made up 58% of the calories, with fats accounting for 25% and protein 16%.
Both diets provided significantly fewer calories than its participants likely would have preferred -- 60% of estimated calorie requirements.
So, not surprisingly, both groups lost weight.
But the folks on the Eco-Atkins diet had greater reductions in LDL and total cholesterol than did the folks in the higher-carb diet.
The abstract of the study, published June 8 in the Archives of Internal Medicine, reaches this conclusion:
A low-carbohydrate plant-based diet has lipid-lowering advantages over a high-carbohydrate, low-fat weight-loss diet in improving heart disease risk factors not seen with conventional low-fat diets with animal products.
Fairly enough, the Low Carb Diets Blog takes issue with the diet used as a comparison:
They could have compared a regular mixed low-carb diet to a vegan or vegetarian low-carb diet. Or compare a high-carb vegan diet to a low-carb vegan diet, where the food sources for the various macronutrients were similar, and only the proportions varied. As it is, the reasons for the results are already being questioned in various media ("It's the soy!" "No, it's the fiber!") as well as in the conclusions written by the authors themselves.
I love that vegetarianism is becoming more mainstream, but I wish that people would just call it what it is and stop trying to put cute names on it to mask it.
But it seems hard to deny there's some potential in this eating plan...
--Tami Dennis
Photo: Soybeans are the friend of vegan dieters. In this study, however, gluten was a better friend. Credit: Kari Goodnough / Bloomberg News
The disturbing part is that a connection apparently exists. For kids, at least.
Researchers at National Taiwan University and the University of Arkansas parsed data from the National Health Interview Survey in Taiwan (where 1 in 4 children is overweight). Their study, published recently in the Journal of Happiness Studies, found some perhaps unsurprising but worth-repeating connections. Among them:
-- Kids ages 2 to 12 who regularly eat fast food (French fries, pizza or burgers) and indulge in soft drinks (sugar-sweetened beverages) are more likely to be overweight. (Yes, yes, just keep going . . . )
-- Moms who turn to fast food are more likely to have kids who turn to fast food.
-- Kids in cities are more likely to consume fast food than kids in small towns. (Think access to the stuff.)
-- Greater fast food consumption is linked to greater soft drink consumption.
-- Kids eat more fast food and guzzle more soft drinks as they get older.
And then the clincher:
-- Kids who regularly scarf down fast food and soft drinks are less likely to be unhappy than kids who don't. More likely to be overweight, yes, but less likely to be unhappy.
There's a conundrum.
The researchers state in their conclusion: "Current and future policy/program interventions that aim to decrease fast food and soft drinks consumption of children to reduce childhood obesity may be more effective if these interventions also focus on ways that could compensate the potential reduction in degree of happiness of children."
Who knew parents had to choose between maximizing their kids' chances for health and maximizing their chances for happiness?
As one colleague put it: "There's a reason they're called Happy Meals."
-- Tami Dennis
Photo: Just the thought of pizza, I'll confess, makes me a little happy too. Credit: Los Angeles Times
They may be vitamin-fortified, antioxidant-laced, sport-specific or caffeine-enhanced, but those liquid calories are still calories. And they add up.
Now two new studies suggest that simply changing our drinking habits can reduce our overall calorie consumption.
In one study, published April 1 in the American Journal of Clinical Nutrition, researchers at Johns Hopkins Bloomberg School of Public Health and elsewhere found that adults who reduced their liquid calorie intake by just 100 calories a day lost a quarter of a kilogram -- just over half a pound -- in six months. (And that's just 100 calories a day -- not even a decent, nonfat mocha.)
The researchers also found that cutting calories from liquids led to more weight loss than cutting calories from solids.
Their conclusion: "These data support recommendations to limit liquid calorie intake among adults and to reduce [sugar-sweetened beverage] consumption as a means to accomplish weight loss or avoid excess weight gain."
Meanwhile, researchers from Columbia Mailman School of Health and elsewhere analyzed data from the National Health and Nutrition Examination Survey and estimated that simply replacing all sugar-sweetened beverages among children and adolescents ages 2 to 19 would save each one 235 calories a day. (That's a pretty easy way to cut back without making kids feel deprived.) That study was published in the April issue of Archives of Pediatrics & Adolescent Medicine.
Their conclusion: "Replacing [sugar-sweetened beverage] intake with water is associated with reductions in total calories for all groups studied."
That journal also offers some free advice for parents, complete with some interesting facts (among which: 20% of male teenagers have four or more sodas a day). The top recommendation: "Eliminate sugary drinks at home. Just don't buy them. Replace with water, milk, or real fruit/vegetable juices. Encourage your child to drink lots of water."
Both studies point out that as our consumption of sugar-sweetened beverages has increased, so has the obesity rate. It doesn't seem like a coincidence.
Perhaps water -- plain water -- might just be the no-calorie, meal-enhancing beverage that we all need. And it's one that wouldn't prime the sweets-loving pump the way that even low-calorie but sweeter drinks might.
Maybe we should all switch.
-- Tami Dennis
Photo: Who knows -- we might get used to it. Credit: Los Angeles Times
Now, if you come here often, you know that loading up on carbohydrates is going to make you pretty chubby. But you notice your fellow diner -- the mouse -- is pretty slim. How does he do it?
This lucky mouse has had a gene knocked out of his genome by researchers in Hei Sook Sul's lab. The observation that mice without this gene can eat all the carbs they want and stay slim -- while other mice fed a high-carb diet do indeed become fat -- leads Dr. Sul to conclude that her lab has found a gene that plays a critical role in the process of converting carbohydrates to fat. And that discovery points to an important new target for drug developers hoping to find a way to prevent and perhaps even reverse obesity in humans.
The discovery of the gene's role in obesity is published in an article in the March 20 issue of the journal Cell.
The gene involved, known as DNA-PK (short for DNA-dependent protein kinase), is widely studied for its role in repairing breaks in the DNA -- a function that has made it critical to cancer research and treatment. But Sul says it was a surprise to discover that the same gene has a key role in the liver's conversion of excess glucose (all that bread, pasta and sugary soda you've failed to work off) to fatty acids.
Not only were mice whose DNA-PK gene had been knocked out 40% leaner than normal mice when all were fed a high-carb, low-fat diet. They also had better blood-lipid profiles, suggesting they'd be at lower risk of developing heart disease.
In an interview, Sul said no one at this point is thinking about gene therapy as a treatment for obesity -- that would be way down the road. Instead, drug developers might look at how the DNA-PK gene calls out other actors to set in motion the conversion of excess calories to fat and find an agent that might disrupt the process.
And if they're successful, you'll be able to join that mouse at the all-you-can-eat pasta bar and look just as svelte as he does.
The low-carb diet versus other diets debate rages on, this time with a new study that shows diets low in carbohydrates may affect cognitive skills.
Yes, by cutting back on carbs people could be cutting back on their mental acuity as well. Researchers in the psychology department at Tufts University in Massachusetts studied 19 women ages 22 to 55, nine of whom chose a low-carb diet, and 10 a low-calorie macronutrient balanced diet recommended by the American Dietetic Assn.
The participants were then given tests before the diets began, a week into the diets, and two and three weeks into the diet, after the low-carb group had carbohydrates put back into their diets. The tests measured attention and long- and short-term memory skills, visual attention and spatial memory.
After the first week, the low-carbers were in carb-deficient mode, and it showed — they had slower response times than the low-calorie group on two cognitive tests relating to memory. On a short-term recall test, the low-carb dieters also fared worse. They outscored the low-calorie group on an attention vigilance task, but researchers point out that in other studies, diets high in protein or fat can actually enhance short-term attention.
Hunger levels stayed the same for both groups, and all lost about the same small amount of weight (about 4.5 pounds). The low-calorie dieters also reported feeling more confused during the middle of the study.
The brain runs primarily on glucose, which it gets from the blood stream after carbs are broken down in the gastrointestinal tract.
"Although this study only tracked dieting participants for three weeks, the data suggest that diets can affect more than just weight," said Holly Taylor, a psychology professor at Tufts and a co-author of the study, in a news release. The study was published in the February 2009 journal Appetite. "The brain needs glucose for energy and diets low in carbohydrates can be detrimental to learning, memory and thinking."
One fear people have about going on a diet for any length of time is that they may suffer from nutritional deficiencies. A study published this week is fairly reassuring, at least for people on several of the most popular diets.
The study, published by British researchers in the Nutrition Journal, found that most people on the popular diets Slim Fast, Atkins, Weight Watchers and Rosemary Conley's "Eat Yourself Slim" diet (a low-fat diet popular in the United Kingdom) typically get enough nutrients. There are some exceptions and some interesting observations, however:
Despite the fact that all of the diets except the Atkins diet advise people to eat more fruits and vegetables, only the dieters in the Weight Watchers one actually did so, and they only added one more portion a day.
People on the Atkins diet had lower intake of dietary fiber.
People on the Atkins diet had no significant changes in their absolute intake of fat per day or in the quantity of saturated fat consumed. The amount of saturated fat intake fell significantly in the other groups.
Atkins dieters had declines in folate, magnesium, calcium, iron and potassium. There was an increase in selenium.
Weight Watchers dieters had declines in riboflavin, niacin, potassium, calcium, magnesium, iron and zinc.
Slimfast dieters had declines in niacin and a rise in zinc.
Rosemary Conley dieters had declines in magnesium, potassium and zinc.
The two-month study found that all the diets resulted in a significant drop in body weight compared with non-dieters in a control group, but there was no real difference between the diets in the amount of weight lost.
Sure, they come in a cute small package, but 100 calories and 4 grams of fat from a mini-M&M pack, and maybe an additional 150 calories and 8 grams of fat from five of those little Chips Ahoy chocolate chip cookies, and pretty soon you're talking real diet-busters.
A study with a free abstract in the Journal of Consumer Research found that people who care the most about counting calories are the ones who consume more calories when packages are smaller. The researchers examined consumer behavior around those mini-packs, marketed to help people control calories.
"Interestingly, one group that over-consumes the mini-packs is chronic dieters -- individuals constantly trying to manage their weight and food intake," the authors write in a news release.
The small packages actually appear to undermine a dieter's intentions. People watching their weight look at the small pack and see a relatively large quantity of itty-bitty sweets. On the other hand, they take the small packaging and bite-sized sweets to be akin to diet food, the authors say.
Through a series of questionnaires, researchers divided people into groups labeled "restrained eaters" (or dieters) and "unrestrained eaters" (people with fewer dietary concerns). They found the dieters consumed more calories from mini-packs than from full-sized packages of the same foods. They also found that, presented with large versus small packages of potato chips, dieters were more reluctant to even open the large packages, but readily dug into the small-sized bags of chips.
It's a classic difference between what people want to believe, and reality.
Even as people understand more about what they should eat to stay slim or lose weight, they don't do it. Proof of that is an annual state-by-state obesity report by CalorieLab. For the third year running, Mississippi takes the prize for the fattest state, with 31.6% of the population obese. Colorado is the slimmest -- only 18.4% of them are obese. California, which inched up 0.4% to 23.1% since 2007, still manged to drop in the national rankings from 36th fattest state to 41st. But it's not anything Californians did. Rather, the state dropped because people in a lot of other states got even fatter.
It's not a pretty picture, and the Department of Agriculture released a study this month that helps explain why it's so hard to eat right. Dietary knowledge is not enough, the report concludes.
What gets in the way of eating whole grains, fruits and vegetables, fish, modest amounts of low-fat chicken and meat is not lack of information. It is, well ... life.
Using data from federal food surveys, researchers found that stress and hunger get in the way of good dietary habits. On a 2,000-calorie-per-day diet, people who wait five hours between meals compared with four hours will eat 52 more calories in that next meal. If they hold off another hour and wait six hours between meals, they'll gobble up an additional 91 calories. And, researchers found, they'll make less-healthy food choices when they do eat.
Where they eat makes a difference. People who eat at a restaurant eat an average of 107 more calories per meal than if they had eaten at home.
Using work hours as a proxy for stress, researchers found that people who work longer hours wait longer between meals, and eat more calories. People who work consume more calories than those who stay home, and the more they work, the more they eat.
"At four hours between meals, an individual who works 40 a week is estimated to eat about 20% more calories than someone who is not employed. At eight hours between meals, the calorie discrepancy jumps to nearly 40%," according to the report.
Knowledge does make some difference, however. A person who scored 50 on the USDA's Diet and Health Knowledge Survey will eat 28% more calories when eating away from home. A person with a score of 100 will eat only 12% more.
Tami Dennis, who takes the word "skeptic" to previously uncharted territory, is the Times' Health and Science editor. She's adamant that pitches promoting awareness days, weeks or months are, by their nature, non-stories. And, because she's an adult, she refuses to use words like "veggies," "tummy" and "yummy."
Rosie Mestel, deputy Health and Science editor, studied genetics before abandoning flies, fungi and DNA for health/medical writing. Her hero is the biologist Ernst Haeckel, whose jellyfish paintings inspired snazzy chandeliers. Her favorite toast-spread is Marmite, a British delicacy made of yeast extract. Her least-favorite word is "millenniums."
Melissa Healy is a staff writer for the Health section reporting from Washington D.C. Healy's a veteran of The Times' National staff, having covered the Pentagon, Congress, poverty and social welfare, the environment, and the White House before shifting to Health in 2003. She writes frequently about mental health and human behavior, about federal health policy, prescription medication and ethics in medicine. More wonk than wellness freak, Healy chooses to believe in the health benefits of coffee and wine, and considers water a better work-out medium than beverage.
Karen Kaplan covers genetics, stem cells and cloning. She and colleague Thomas H. Maugh II comprise about 25% of the unofficial MIT-Alumni-in-Journalism Club, and she is proud to have taken more math (5) than English (0) courses in college. Her contributions to Booster Shots will, she hopes, appear more frequently than postings to her mommy blog.
Thomas H. Maugh II has been a science and medical writer at the Times for 23 years. Before that, he was on the staff of the journal Science for 13 years.
He has bachelor's degrees in English and chemistry from MIT and a doctorate in chemistry from UC Santa Barbara.
After a brief stint as a sports writer, Shari Roan turned to health journalism and has covered the topic for The Times for 18 years. She is the author of three books and the mother of two daughters, both teenagers who refer to her as a "health freak." She likes to jog, watch baseball and is very happy that dark chocolate contains some health benefit.
Jeannine Stein writes about fitness, sports medicine and obesity for the Health section. She’s a gym rat from way back and never met an elliptical trainer she didn’t like. Well, maybe one or two. She tempers exercise with a steady diet of reality television because she believes it’s all about balance.
Yes, by cutting back on carbs people could be cutting back on their mental acuity as well. Researchers in the psychology department at 
A study with a free 
