High-carb diets may put dieters in better moods

The high-protein versus high-carb diet debate continues with the release of a new study that looked at something usually left out of the weight loss equation: mood.

Most studies on these two popular weight loss methods -- and on diets in general -- typically focus on pounds lost, pounds kept off and cardio-vascular function. But in a study published today in the Archives of Internal Medicine, Australian researchers took a more holistic approach. In addition to weight they also measured mood, discovering that those who stayed on a high-carbohydrate, low-fat diet for a year had better moods than those who were on a low-carbohydrate, high-fat diet, although the two groups lost about the same amount of weight.

The researchers randomly assigned 106 overweight and obese men and women to either a low-carb, high-fat diet or a high-carb, low-fat diet for a year. The groups were somewhat restricted in their calorie intake -- women were allowed 1,400 calories, and men about 1,700. On the low-carb plan, diets consisted of 4% carbohydrates, 35% protein and 61% fat, while the high-carb was composed of 46% carbohydrates, 24% protein and 30% fat.

The participants' weight was noted at weeks eight, 24, 40, and 52, and their mood was evaluated via three questionnaires that measured various aspects of mood, including tension-anxiety, depression-dejction and anger-hostility.

Both groups lost a significant amount of weight -- about 30 pounds. In the early weeks of the study both groups showed an improvement in mood. However, over time that changed. Mood improvements remained in the high-carb group but went back to original levels for the low-carb group.

Researchers speculate that the results could be evidence that it's tough sticking with a low-carb diet over a longer period of time, especially in cultures that favor carbohydrates. "Over the long term, trying to maintain that dietary pattern may mean coming across a lot of challenges," said Grant Brinkworth, lead author of the study and a research scientist at the Commonwealth Scientific and Industrial Research Organisation -- Food and Nutritional Sciences in Adelaide. "That may cause cause a negative mood impact, even though you’re getting a good weight loss." That bad mood might eventually affect adherence to the diet down the road as well, he added.

Another theory is that in a low-carb diet, lower levels of serotinin may be produced. Serotonin is a neurotransmitter responsible for lending a feeling of happiness and well-being, and eating carbs can increase its release.

-- Jeannine Stein

Photo credit: Krista Simmons / Los Angeles Times

Halloween's over, but the calorie danger is just beginning. Here's help.

Trick or treating is for kids, but the candy sure can be tempting to grown-ups. Whether you’re inclined to raid your children's loot or help yourself to the leftovers that didn’t get handed out at your house Saturday night, here are some websites that might persuade you to beat back that urge to eat a dozen Skittles fun packs in one sitting:

• Good Housekeeping has this Halloween Candy Quiz that reveals the calorie count of popular goodies. Try it and find out which will do more damage to your waistline – two Rolos or a small pack of M&Ms?
• About.com offers this calculator to help you compute how many miles you’ll need to walk to burn off such treats as candy corn, Tootsie Rolls and candy bars of all sizes.
• If scare tactics work best for you, head straight to Evil Halloween Candy, which lists the calorie count of favorites including Kit Kat bars, York Peppermint Patties and Milk Duds. (Their counts are somewhat higher than I found on other sites.)
• This post from the MomLogic blog includes additional nutritional information, such as fat, carbs and protein. (Apparently each Reese’s peanut butter cup contains 1 gram of protein.) Some serving sizes on this site are much bigger than the usual Halloween “fun size.”
• And it may be too late now, but WebMD offers tips for those who wish to indulge more responsibly. For example, stick to plain chocolate bars instead of candies loaded with caramel, coconut and other goodies. Or select dark chocolate bars instead of white chocolate.

-- Karen Kaplan

Photo: Proceed with caution. Photo credit: Los Angeles Times

Recommendations for new school meal nutrition standards

The nutrition standards behind the National School Lunch Program and the School Breakfast Program have not been updated since 1995. Today, the federal Institute of Medicine is issuing a report recommending new standards, calling for more produce, more whole grains. And for the first time, a limit to calories.

Thirty million children eat school lunch, and 10 million eat school breakfast -- and the IOM panel says it hopes new standards will help those children develop good habits that they carry into adulthood. That, the panel says, should help curb obesity and other health problems associated with diet.

The panel's recommendations go to the U.S. Department of Agriculture for possible implementation. It was the USDA which requested the report.

The panel says new standards would cost money -- for food as well as for training and capital improvements. But it says food costs would go up by less than 10% for breakfast and 25% or less for lunches. The government now spends $8.7 billion a year in reimbursements for school meals to school districts.

The recommendations are meant to bring school food in line with the dietary guidelines the government issues for Americans. It seeks to have the amount of sodium in school meals reduced by more than half over the next decade.

Among its recommendations: that calories be limited, based on age level, for breakfast and lunch, and that the sodium level for a typical lunch be eventually reduced to 740 milligrams. It also sets out targets for weekly servings of fruits and vegetables, and it calls for more whole grains.

"It's about time," says Matthew Sharp of the California Food Policy Advocates and one of the people who testified before the panel. Meals, he says, should be nutritious and affordable and they also should "teach kids healthy habits" and expose them to a variety of foods.

-- Mary MacVean

Your tax dollars at work ... for your diet

Let’s say you’re about to dig into a quarter-pound cheeseburger dripping with ketchup, mustard and mayonnaise. Then you hesitate. Is this a nutritious choice?

Luckily, you can find the answer at MyFood-a-pedia, a new online service from the U.S. Department of Agriculture that lets you search for nutritional information on more than 1,000 items.

According to MyFood-a-pedia, the naked cheeseburger on a bun contains 552 calories and includes 1.5 ounces of meat, 3 ounces of grains and half a cup of milk. But 195 of its calories come from “extras” like solid fats and added sugars. Factoring in all the condiments boosts the total calories to 669. Adding lettuce and tomato raises it slightly more, to 673, but then the burger gets credit for containing a quarter cup of vegetables.

A medium-sized fast-food order of French fries adds an additional 457 calories to the meal, including 224 from fats and sugars, MyFood-a-pedia says. A can of soda contains an additional 155 calories, all but one of which is in the unhealthful “extras” category.

MyFood-a-pedia has nutritional information on a gamut of items, including raw apples (72 calories each); applesauce (97 calories in a half-cup serving); apple pie (356 calories a slice); apple cider (117 calories in a cup); Apple Jacks (also 117 calories a cup); and Waldorf salad (121 calories in each half-cup scoop).  

Nutritional information on two foods can be compared side by side. (Turns out a serving of Froot Loops has one fewer calorie than Apple Jacks.) The service was unveiled last week in a tweet from the USDA.

-- Karen Kaplan

Image: USDA

This number screams: Diet!

Confused by the various recommendations from doctors and nutritionists on how much he should weigh, a University of Nevada, Reno, statistician has devised a better way for people to gauge their weight.

The Maximum Weight Limit is a tool to advise people of the number that should set off alarm bells and whistles when they step on the scales. Using calculations, George Fernandez devised the tool so that it closely corresponds to weight recommendations listed on body mass index charts. But it's far easier to calculate and remember compared to BMI.

"When you drive, you have a speed limit. This is similar to that concept," says Fernandez, director of the Center for Research Design and Analysis. "This number tells people, 'This is your maximum weight. You should not going over that weight.' It's a simple concept that should stay in their heads."

The Maximum Weight Limit is calculated on a baseline height and weight. A man who is 5 feet 9 should weigh no more than 175 pounds. A woman who is 5 feet should weigh no more than 125 pounds. To find your Maximum Weight Limit, calculate how much taller or shorter you are in inches. A man should subtract or add 5 pounds for every inch taller or shorter than 5 feet 9. A woman should add or subtract 4.5 pounds for every inch she differs from the baseline height of 5 feet.

The number does not reflect a person's ideal weight, Fernandez says, because people differ in their build and muscle mass. The tool is meant to give people a stop sign. "This is something strict that says, 'This is your limit,' " he says. People who reach their limit should change their lifestyle to eat healthier and exercise more or should seek professional guidance to curtail further weight gain. "It's time to intervene and take steps immediately," he says.

Fernandez came up with the formula after talking to doctors and nutritionists about his own weight. "They all came up with different numbers: a weight range, ideal weight, healthy weight, BMI." After delving into research on weight guidelines, Fernandez says he was struck by how complex the BMI calculation was. BMI was introduced by a Belgian statistician more than 200 years ago, Fernandez says. "It's a fine, valid measurement for identifying or diagnosing overweight and obesity. But for common people, it's hard."

Fernandez is presenting his theory today at a conference of the Nevada Public Health Assn. He plans to begin testing the Maximum Weight Limit to see whether people find it helpful and to identify whether the number could replace BMI in clinical studies on weight.

-- Shari Roan

Photo: Maximum Weight Limit charts for men and women. Credit: George Fernandez, University of Nevada, Reno.

Rodent of the Week: Fat messes with your mind

The brain is increasingly the target for understanding why people overeat and become obese. A new study, in rodents, shows that some forms of dietary fat apparently sabotage a system in the body that is designed to prevent overeating.

The study, from researchers at UT Southwestern Medical Center, showed that certain fats cause the brain to send messages to the body to ignore the normal mechanisms involved in weight regulation. Those mechanisms are hormones, such as leptin and insulin, that normally work by telling us we're full and should stop eating, said Dr. Deborah Clegg, the lead author of the study. One type of saturated fat, palmitic acid, is particularly effective at blunting the normal hormone response. Palmitic acid is found in butter, cheese, ice cream, milk and beef.

"Normally, our body is primed to say when we've had enough," Clegg said in a news release. "But that doesn't always happen when we're eating something good. What we've shown in this study is that someone's entire brain chemistry can change in a very short period of time. Our findings suggest that when you eat something high in fat, your brain gets 'hit' with the fatty acids, and you become resistant to insulin and leptin. Since you're not being told by the brain to stop eating, you overeat."

The researchers also found that this effect lasts for about three days. So one splurge of foods high in fatty acids can cause a lengthy eating binge.

Though the study was in animals, Clegg said that saturated fat "causes you to eat more."

The study appears in the September issue of the Journal of Clinical Investigation.

-- Shari Roan

Photo credit: Advanced Cell Technology, Inc.

Try rye for a filling breakfast and weight loss

Dieters are often told to eat a filling breakfast in order to avoid overeating later in the day. The latest addition to that advice is to eat rye bread. The study, from Swedish researchers, found that rye increases the feeling of being full and leads to reduced food intake later in the day (for as long as eight hours) compared to eating wheat bread. The strongest effect was for rye bread made with rye bran.

Satiety -- feeling full -- is of great interest to nutritionists and weight-loss experts. The idea is to avoid eating high-calorie foods that leave you feeling hungry an hour later and instead eat foods that reduce hunger. Breakfast is a good place to start, the authors say. But they note: "In the Western world the majority of the whole grain products eaten are based on wheat, while the consumption of oats and especially rye and barley is much lower." Rye is consumed more often in Northern, Central and Eastern Europe.

"That rye possibly has superior satiating properties may be due to its high dietary fiber content and possibly fiber composition," they wrote. People eating rye bread also had a lower insulin response.

The bread tasted good too, the authors said. "The levels of rye used in the breads were based on realistic amounts to create palatable, voluminous bread," they wrote.

The study is published in the current issue of the Nutrition Journal.

-- Shari Roan

Photo credit: Michael Urban / AFP / Getty Images

Rodent of the Week: Low-carb diets affect blood vessels

Low-carb diets can help people lose weight. But the diets may have a downside if followed over the long term, according to a researcher whose curiosity was piqued after she observed a number of heart attack patients who had been on low-carb, high-protein diets. According to the study, published this week in the Proceedings of the National Academy of Sciences, rats on the diets had an increase of plaque in the arteries of the heart and also had an impaired ability to form new blood vessels in tissues deprived of blood flow.

Blood tests of people on low-carb diets suggest the diets are safe. But, said the lead author of the paper, Dr. Anthony Rosenzweig, "our research suggests that, at least in animals, these diets could be having adverse cardiovascular effects that are not reflected in simple serum markers."

In the study, researchers fed mice a low-carb, high-protein diet; a standard mouse "chow" diet or a typical Western diet (43% carbohydrate, 42% fat and 15% protein) for 12 weeks before examining their cardiovascular system. The rats' cholesterol levels did not change, and the rats on the low-carb diet gained 28% less weight than mice on the Western diet. However, when researchers looked at the animals' blood vessels, the low-carb mice had a 15.3% increase in plaque accumulation compared with 8.8% in the Western diet group.

The study suggests that there may be a disconnect between cholesterol levels and what is occurring in blood vessels. Moreover, vascular health may be directly influenced by the amount of protein and carbohydrate in a diet.

"For now, it appears that a moderate and balanced diet, coupled with exercise, is probably best for most people," Rosenzweig said.

-- Shari Roan

Photo credit: Advanced Cell Technology Inc.

Rodent of the Week: Nine days of bad food

Ever wonder how you'd feel if you completely changed your diet for a week to 10 days? Scientists experimenting with rats did just that. Granted, we still don't know how the rats feel. But when they were switched from a low-fat diet to a high-fat diet they showed serious reductions in their physical endurance and cognitive ability.

"After just nine days, they were only able to run 50% as far on a treadmill as those that remained on the low-fat diet," said the lead author of the study, Dr. Andrew Murray, now at the University of Cambridge.

Endurance depends on how much oxygen can be supplied to muscles and how efficiently muscles release energy by burning the fuel supplied by food. Fat as a fuel is less efficient, but studies on how various diets affect physical performance have been mixed, the authors said.

The rats in the study showed a 30% decline in running stamina after only five days. They also began making more mistakes in a maze task. The rats also had significantly bigger hearts after only nine days.

The study "shows that high-fat feeding even over short periods of time can markedly affect gene expression," Kieran Clarke, chief of the research team at Oxford, said in a news release. "By optimizing diets appropriately we should be able to increase athletes' endurance and help patients with metabolic abnormalities improve their ability to exercise and do more."

The study is published in the current edition of the FASEB Journal.

-- Shari Roan

Photo: Advanced Cell Technology Inc.

Which Americans have a bigger sweet tooth?

The World Health Organization suggests that no more than 10% of total calories come from sugars. Not surprisingly, Americans far surpass that mark: A 2005 study of U.S. diets found that we consume an average of 22.9 teaspoons of sugar per day, which works out to 16.6% of total calories.

What’s wrong with that, you ask? Diets high in added sugars result in more dental cavities. And researchers strongly suspect – but have not definitively proven – that high consumption is linked to unhealthy weight gain, in part because the processed foods that contain added sugars displace healthier alternatives, like fruits and vegetables.

Researchers from the National Institutes of Health in Bethesda, Md., and colleagues from Information Management Services Inc. in Silver Spring, Md., wondered whether intake of added sugars was linked to race, ethnicity, income or educational status. To find out, they analyzed data from 30,805 adults who participated in the 2005 National Health Interview Survey. Among other things, participants were asked how frequently they consumed soda; fruit drinks; doughnuts, sweet rolls and muffins; and cake, cookies and pie. The researchers converted their responses into servings of added sugars using other data on portion sizes.

In the study, added sugars were defined as “white sugar, brown sugar, raw sugar, corn syrup, corn-syrup solids, high-fructose corn syrup, malt syrup, maple syrup, pancake syrup and fructose sweetener.” Sugars that occur naturally in milk and fruit were not included in the analysis.

So, who has the biggest sweet tooth?

Generally speaking, men ate more added sugars than women – the average daily intake of added sugars was 18.8 teaspoons for men and 12.7 for women. Young adults ate more than older adults – 18.3 teaspoons per day among people ages 18 to 39, compared with 11.7 teaspoons per day for people who had already reached their 60^th birthdays, according to results of the study, published in the August issue of the Journal of the American Dietetic Assn.  

There were also distinct patterns according to race and ethnicity. Asian Americans ate the least added sugars (12.9 teaspoons per day), followed by Hispanics (14.9 teaspoons per day) and whites (15.3 teaspoons per day). African Americans and Native Americans essentially tied at slightly more than 16 teaspoons of added sugar per day, the study found.

Those with more education and higher household incomes ate less than people who were lower on the income and education scales. The results weren’t completely surprising, the authors noted, since the least expensive foods have the most added sugars. Several previous studies have linked low income to bigger body sizes.

-- Karen Kaplan

Photo: Mmmmm, added sugars ...... Photo credit: Seth Wenig/Associated Press