Australia - More Veggies In My Asian Takeout, Please

Asian take-away foods must include more vegetables to meet the recommended dietary guidelines for vegetable consumption, says a new study.

Research from Australia into the nutritional value of Chinese, Thai, and Singaporean take-away foods has shown that an increase in vegetable content is needed to meet the recommended dietary guidelines for vegetable consumption.

Dr. Christina Pollard, Curtin University Adjunct Senior Research Fellow, Center of Behavioral Research in Cancer Control, said that although Asian menu items are often considered a healthy option, there is little information available about their relative healthfulness.

“The demand for convenient eating options has led to an increase in foods eaten away from home and consumers are looking for healthy options when they eat out,” Pollard said.

The research, published in the Food and Nutrition Science Journal, aimed to pilot a simple method for measuring the vegetable content of popular Asian dishes for use in nutrition education.

Thirty vegetable containing take-out dishes from three Asian restaurants (Chinese, Thai, and Singaporean) in Perth were photographed and weighted with, and without the vegetables.

Contrary to popular belief, all three of the Asian cuisines sampled were not a good source of vegetables, said Pollard. There was, however, a wide and consistent variation in the vegetable content within each cuisine.

Dietary guidelines recommend increasing consumption of fruits and vegetables to protect against chronic diseases, such as diabetes and cancer, and maintenance of a healthy weight. Currently, most adults consume well below the recommended five 75 gram standard servings per day.

“The trends for increasing consumption of take-away foods, particularly Asian take-away, point to an urgent need to advise consumers to select the vegetable dense dishes and to encourage the food service industry to increase the vegetable content of Asian meals,” Pollard said.

“Nutrition educators should encourage Asian food businesses to increase the vegetable content of their menus and advise customers to choose at least one vegetarian dish to encourage healthy lifestyles.”

The article can be found at: Pollard C et al. (2012) A Simple Approach Assessing the Vegetable Content of Asian Takeout Meals with Nutrition Education Potential.

Source: Curtin University Australia;

Health & Medicine

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Australia - Brain Circuit Makes It Harder For Obese People To Lose Weight

Researchers in Australia explain why when obese people diet, they end up losing less weight.

Imagine you are driving a car, and the harder you press on the accelerator, the harder an invisible foot presses on the brake. That’s what happens when obese people diet – the less food they eat, the less energy they burn, and the less weight they lose.

While this is a known phenomenon, scientists at Sydney’s Garvan Institute of Medical Research and the University of New South Wales (UNSW) have pinpointed the exact brain circuitry behind it using various mouse models.

In the journal Cell Metabolism, Dr. Shu Lin, Dr. Yanchuan Shi, and Professor Herbert Herzog and his team show that the neurotransmitter Neuropeptide Y (NPY), known for stimulating appetite, also plays a major role in controlling whether the body burns or conserves energy.

“This study is the first to identify the neurotransmitters and neural pathways that carry signals generated by NPY in the brain to brown fat cells in the body. It is also the first to show a direct connection between Arc NPY, the sympathetic nervous system and the control of energy expenditure,” said Herzog.

The researchers found that NPY – produced in a particular region of the brain called the arcuate nucleus (Arc) of the hypothalamus – inhibits the activation of ‘brown fat,’ one of the primary tissues where the body generates heat.

While NPY also influences other aspects of the sympathetic nervous system such as heart rate and gut function, its control of heat generation through brown fat seems to be the most critical factor in the control of energy expenditure.

“When you don’t eat, or dramatically curtail your calorie intake, levels of NPY rise sharply. High levels of NPY signal to the body that it is in ‘starvation mode’ and should try to replenish and conserve as much energy as possible. As a result, the body reduces processes that are not absolutely necessary for survival,” he said.

Until the twentieth century, people did not have ready access to foods high in fat and sugar, said Herzog. So in evolutionary terms, the body had mechanisms in place only to prevent weight loss, he said.

“Obesity is a modern epidemic, and the challenge will be to find ways of tricking the body into losing weight – and that will mean somehow circumventing or manipulating this NPY circuit, probably with drugs,” he said.

The article can be found at: Shi YC et al. (2013) Arcuate NPY Controls Sympathetic Output and BAT Function via a Relay of Tyrosine Hydroxylase Neurons in the PVN.

Source: Garvan Institute of Medical Research;

Health & Medicine

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USA - Diet may treat some gene mutations

Scientists have moved a step closer to correcting some unhealthy gene mutations with diet, according to a new research report appearing in the April 2012 issue of the journal Genetics. 

Researchers from the University of California, Berkeley, determined variations and responses to vitamin treatment in the human cystathionine beta synthase gene, which when defective, causes the disease homocystinuria, an inherited metabolic disorder sometimes treatable with vitamin B6.

After the analysis, scientists correlated specific gene mutations with severity of the disease, ranging from perfectly healthy and functional to severe and untreatable. Although the current study focused on homocystinuria, testing the effects of naturally occurring gene variations using surrogate organism genetics can be applied to other inherited disorders, such as neural tube defect, cleft palate, and blindness.

"The era of personal genome sequences is upon us, but there is a growing gap between the ability to sequence human genomes and the ability to understand the significance of variation in genome sequences," said Jasper Rine, Ph.D., the principal investigator of this research in the Department of Molecular and Cell Biology at the California Institute of Quantitative Biosciences at the University of California, Berkeley. "This study demonstrates one way to close the gap; the data separate gene variants into distinct classes, including a group amenable to dietary intervention."

To make their determination, scientists "swapped" the cystathionine beta synthase gene of baker's yeast with the gene from humans to test which variants were healthy, treatable, or untreatable with additional vitamin B6. As a result, the study clarified the function of 84 DNA sequence variants in this gene, which will help physicians more effectively treat patients based on their particular genotypes. In addition, this approach opens doors for future studies examining other human genes that similarly cross over between humans and yeast.

"We may have the DNA sequence of the human genome, but we're still trying to figure out what it means," said Mark Johnston, Editor-in-Chief of the journal Genetics. "This study moves us a step closer toward better understanding the genetic variability among people. More immediately, knowledge of these gene mutations will help physicians prescribe treatment based on genotype rather than outward symptoms or trial and error."

Biology & Nature

Source: Genetics Society of America