Exercise shows opposing effects on appetite

Good morning friends. Exercise seems to simultaneously make people hungrier, yet more readily satisfied by a meal -- and differences in these responses from person to person may help explain why some exercisers shed pounds more easily than others, researchers say.

In a study of 58 overweight and obese adults who started an exercise regimen, researchers found that exercise tended to boost participants' hunger before a meal, compared with their sedentary days.

On the other hand, they were also more easily satisfied by their morning meal than they had been before becoming active.

But while both effects were generally at work across the study group, there were subtler differences between participants who were more successful in their weight loss and those whose extra pounds stubbornly hung on.

In general, exercisers who did not meet their expected weight loss were both hungrier after fasting -- that is, right before breakfast -- and throughout the day, compared with their hunger ratings at the study's start.

In contrast, those who were more successful in shedding pounds generally saw their pre-breakfast appetites increase after becoming active. But they were not hungrier throughout the day.

"The reason that some people are more successful (at weight loss) could be due to a lesser increase in appetite and the prevention of an increase in food intake," lead researcher Dr. Neil King, an associate professor at Queensland University of Technology in Brisbane, Australia, told Reuters Health in an email.

But the bottom line for new exercisers, he said, is that they should not throw in the towel if they start feeling more hungry than normal -- or fail to shed as many pounds as they'd been hoping.

Other research shows that exercise has health benefits -- like improved cardiovascular fitness, and lower blood pressure and cholesterol -- even if weight loss is modest.

For the current study, published in the American Journal of Clinical Nutrition, King's team had 58 overweight men and women go through a 12-week supervised exercise regimen designed to burn 500 calories per session.

At the beginning and end of the study, participants were given a breakfast of cereal and toast, and were asked to rate their hunger before the meal, immediately after and throughout the rest of the day.

After 12 weeks, 32 participants had lost the expected amount of weight based on the calories they burned during exercise; 26 had not. On average, both groups showed a revved up appetite before breakfast on week 12, but daily hunger was greater in those who had not lost a substantial amount of weight.

Both groups of exercisers, though, seemed to be more readily satisfied by their breakfast than they had been before becoming active.

It's not clear why these two different appetite effects arise from exercise. But physical activity, while spurring hunger, may also boost the sensitivity of the body's fullness-signaling system, according to King's team.

"The key messages," King said, "are exercise is good for you, don't expect unrealistic weight loss and don't give up exercising just because of lower-than-expected weight loss." - Indian Express

Yogurt can help lose excess weight

Taking probiotics after Roux-en-Y gastric bypass surgery can help obese patients to lose weight more quickly, according to a new study. Probiotics are the so-called ‘good’ bacteria found in yogurt as well as in over-the-counter dietary supplements that help in the digestion of food.

New research from the Stanford University School of Medicine and Stanford Hospital & Clinics suggests that patients who take probiotics after the gastric-bypass procedure tend to shed more pounds than those who don't take the supplements.

"Surprisingly, the probiotic group attained a significantly greater percent of excess weight loss than that of control group," said John Morton, MD, associate professor of surgery at the medical school who wrote the paper with lead author Gavitt Woodard, a third-year medical student, and five other medical students at the Surgery Center for Outcomes Research and Evaluation in Stanford''s Department of Surgery.

The researchers followed 44 patients on whom Morton had performed the procedure from 2006 to 2007. Patients were randomized into either a probiotic or a control group. Both groups received the same bariatric medical care and nutritional counseling, as well as the support of weight-loss study groups. Both groups also were allowed to consume yogurt, a natural source of probiotics.

In addition, the probiotic group consumed one pill per day of Puritan''s Pride, a probiotic supplement that is available online and in many stores. Morton has no financial ties to the company that makes the supplement. The study showed that at three months, the probiotics group registered a 47.6 percent weight loss, compared with a 38.5 percent for the control group.

The study also found that levels of vitamin B-12 were higher in the patients taking probiotics — a significant finding because patients often are deficient in B-12 after gastric-bypass surgery. The probiotics group had B-12 levels of 1,214 picograms per milliliter at three months, compared with the control group''s levels of 811 pg/mL. Morton said he now recommends probiotic supplements to his patients, and he plans to continue to look for ways to enhance the outcomes from the procedure. The study has been published in the July issue of the Journal of Gastrointestinal Surgery – The Times of India

Aerobics help in weight loss

Sixty minutes of vigorous aerobic exercises on a treadmill is better than 90 minutes of weight-lifting in suppressing appetite.

Aerobics do so by modifying release of two key appetite hormones, ghrelin and peptide YY, while weight-lifting affects the level of only ghrelin, according to a new study.

This line of research may eventually lead to more effective ways to use exercise to help control weight, according to co-author, David J. Stensel of Loughborough University in Britain. There are several hormones that help regulate appetite, but the researchers looked at two of the major ones, ghrelin and peptide YY. Ghrelin is the only hormone known to stimulate appetite. Peptide YY suppresses appetite.

Ghrelin was discovered by researchers in Japan only about 10 years ago and was originally identified for its role as a growth hormone. Only later did its role in stimulating appetite become known. Peptide YY was discovered less than 25 years ago.

In this experiment, 11 male university students did three eight-hour sessions. During one session they ran for 60 minutes on a treadmill, and then rested for seven hours.

During another session they did 90 minutes of weight lifting, and then rested for six hours and 30 minutes. During another session, the participants did not exercise at all, said a Loughborough release.

During each of the sessions, the participants filled out surveys in which they rated how hungry they felt at various points. They also received two meals during each session. The researchers measured ghrelin and peptide YY levels at multiple points along the way.

They found that the treadmill (aerobic) session caused ghrelin levels to drop and peptide YY levels to increase, indicating the hormones were suppressing appetite. However, a weight-lifting (non-aerobic) session produced a mixed result. Ghrelin levels dropped, indicating appetite suppression, but peptide YY levels did not change significantly.

Based on the hunger ratings the participants filled out, both aerobic and resistance exercise suppressed hunger, but aerobic exercise produced a greater suppression of hunger.

The changes the researchers observed were short term for both types of exercise, lasting about two hours, including the time spent exercising, Stensel reported.

The study appears in the online edition of The American Journal of Physiology-Regulatory, Integrative and Comparative Physiology.

fer: thetimesofindia

Nuts help cut risk of heart disease

Good morning friends. This article is good for the nuts lovers. I’m sure that everyone will eat nuts to prevent heart ailment. This has reference to The Times of India.

Here's a health tip in a nutshell: Eating a handful of nuts a day for a year — along with a Mediterranean diet rich in fruit, vegetables and fish — may help undo a collection of risk factors for heart disease.

Spanish researchers found that adding nuts worked better than boosting the olive oil in a typical Mediterranean diet. Both regimens cut the heart risks known as metabolic syndrome in more people than a low-fat diet did.

"What's most surprising is they found substantial metabolic benefits in the absence of calorie reduction or weight loss," said JoAnn Manson, chief of preventive medicine at Harvard's Brigham and Women's Hospital. In the study, the people who improved most were told to eat about three whole walnuts, seven or eight whole hazelnuts and seven or eight whole almonds. They didn't lose weight, on average, but more of them succeeded in reducing belly fat and improving their cholesterol and blood pressure.

Manson, who wasn't involved in the study, cautioned that adding nuts to a western diet — one packed with too many calories and junk food — could lead to weight gain and more health risks.

"But using nuts to replace a snack of chips or crackers is a very favorable change to make in your diet," Manson cautioned.

The American Heart Association says that over 50 million Americans have metabolic syndrome, a combination of health risks, such as high blood pressure and abdominal obesity.

Nuts help people feel full while also increasing the body's ability to burn fat, said lead author Jordi Salas-Salvado of the University of Rovira i Virgili in Reus, Spain.

"Nuts could have an effect on metabolic syndrome by multiple mechanisms," Salas-Salvado said. Nuts are rich in anti-inflammatory substances, such as fiber, and antioxidants, such as vitamin E. They are high in unsaturated fat, a healthier fat known to lower blood triglycerides and increase good cholesterol.