Category: Nutrition

Attention-deficit/hyperactivity disorder (ADHD) affects approximately ten percent of children worldwide, yet its causes are not well understood. Now, a study led by Susan Korrick, MD, MPH, of Brigham and Women's Hospital (BWH), and Sharon Sagiv, PhD, MPH, of Boston University School of Public Health, and published in the online version of the Archives of Pediatrics & Adolescent Medicine on October 8, 2012, links low-level prenatal mercury exposure with a greater risk of ADHD-related behaviors.

The study also finds that maternal fish consumption during pregnancy can help reduce the risk of ADHD-related behaviors in children. This duality is possible because many types of fish have low levels of mercury, so it is possible for a pregnant woman to eat nutritionally beneficial fish without being exposed to much mercury.

"These findings underscore the difficulties pregnant women face when trying to balance the nutritional benefits of fish intake with the potential detriments of low-level mercury exposure," said Dr. Korrick.

Dr. Sagiv agrees this study provides an important public health message, saying, "Women need to know that nutrients in fish are good for the brain of a developing fetus, but women need to be aware that high mercury levels in some fish pose a risk."

This analysis involved approximately 400 children born in New Bedford, Massachusetts between 1993 and 1998. Shortly after their mothers gave birth, researchers collected hair samples from the mothers and analyzed them for mercury. They also gave the mothers a questionnaire to determine their fish consumption during pregnancy. Eight years later, researchers followed up with the children and administered standardized tests to determine behaviors related to ADHD.

Researchers found an increased risk of childhood ADHD-related behaviors with increasing maternal hair mercury levels. These mercury levels were lower than levels shown to be potentially hazardous in most previous studies. Additionally, researchers found a reduced risk of ADHD-related behaviors in children whose mothers reported eating more than two servings of fish per week, which is a higher number of servings than is currently recommended by the United States Food and Drug Administration and Environmental Protection Agency.

The study did not examine what types of fish are best for a pregnant woman to eat, but previous studies have shown women should avoid fish that are high in mercury, such as shark, swordfish, king mackerel and fresh tuna. Fish that are low in mercury, such as flounder, haddock, and salmon, are safer to eat and good sources of nutrition.

NewsPsychology (Oct. 10, 2012) — One of the body’s satiation hormones, neurotensin, could raise women’s risk of suffering one of three common and serious conditions: diabetes, cardiovascular disease and breast cancer. There is also a connection between the hormone and premature death in women, especially from cardiovascular disease.

The findings have been presented in a study from Lund University in Sweden, published in the Journal of the American Medical Association.

“It was surprising to find such a clear link to the risk of type 2 diabetes and cardiovascular disease as well as to breast cancer. Obesity is a common risk factor for all three conditions, but the connection with neurotensin is not explained by obesity or other known risk factors,” says Professor Olle Melander from the Department of Clinical Sciences at Lund University, who is also a consultant at Skåne University Hospital.

“This is the first time a satiation hormone has been linked to these three common diseases in women. It therefore opens up a new field for continued research on risk assessment and preventive treatment,” says Professor Marju Orho-Melander from the Department of Clinical Sciences at Lund University, one of the authors of the study.

It is interesting that the findings apply specifically to women. In the case of breast cancer this is obvious, but a better understanding of the development of cardiovascular disease in women is greatly needed.

The connection between neurotensin and these conditions in women was seen to be so strong that it has a clear impact on the patient’s life expectancy. The strong connection also means it is appropriate to use neurotensin as a clinical risk marker for the conditions, in the view of the researchers. This provides new opportunities for early identification of women who are likely to develop cardiovascular disease, which cannot be predicted with the current known risk factors. This makes it possible to initiate preventive treatment at an early stage.

“Because the hormone circulates around the body in the blood, levels can be measured with a normal blood test, which is an advantage,” explains Olle Melander.

The results were obtained through analysis of blood samples from over 4 600 people who took part in the Swedish population study Malmö Diet and Cancer. The participants gave blood samples over several years and the researchers saw a link between the level of neurotensin and the women who went on to develop one of the three diseases.

A low-fat diet reduces neurotensin production and could therefore be one way to regulate neurotensin levels, believe Olle Melander and Marju Orho-Melander. However, they point out that if neurotensin is to work as a target for treatment, a causal relationship must first be established. They hope to be able to identify this relationship through genetic studies that are currently underway.

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Story Source:

The above story is reprinted from materials provided by Lund University, via AlphaGalileo.

Note: Materials may be edited for content and length. For further information, please contact the source cited above.

Happiness and mental health are highest among people who eat seven portions of fruit and vegetables a day, according to a new report.

Economists and public health researchers from the University of Warwick studied the eating habits of 80,000 people in Britain. They found mental wellbeing appeared to rise with the number of daily portions of fruit and vegetables people consumed. Wellbeing peaked at seven portions a day.

The research was carried out in conjunction with Dartmouth College in the USA and is due to be published in the journal Social Indicators Research.

Most western governments currently recommend '5 a day' for cardiovascular health and as protection against cancer risk.

In Britain today, a quarter of the population eat just one portion or no portions of fruit and vegetables per day. Only a tenth of the British population currently consume the magic number of seven or more daily portions. The study does not distinguish among different kinds of fruits and vegetables and it defines a portion as approximately 80 grams.

Study co-author Professor Sarah Stewart-Brown, Professor of Public Health at Warwick Medical School, said "The statistical power of fruit and vegetables was a surprise. Diet has traditionally been ignored by well-being researchers."

She emphasized that much remained to be learned about cause-and-effect and about the possible mechanisms at work, and that randomized trials should now be considered.

Fellow co-author, economist Professor Andrew Oswald from the Centre for Competitive Advantage in the Global Economy (CAGE) in the Department of Economics at the University of Warwick, said: "This study has shown surprising results and I have decided it is prudent to eat more fruit and vegetables. I am keen to stay cheery."

— Researchers at the University of Michigan have determined how the hormone leptin, an important regulator of metabolism and body weight, interacts with a key receptor in the brain.

Leptin is a hormone secreted by fat tissue that has been of interest for researchers in obesity and Type 2 diabetes since it was discovered in 1995. Like insulin, leptin is part of a regulatory network that controls intake and expenditure of energy in the body, and a lack of leptin or resistance to it has been linked to obesity in people.

Although there can be several complex reasons behind leptin resistance, in some cases the underlying cause is malfunction of the leptin receptor in the brain. An understanding of how leptin and its receptor interact could lead to new treatments for obesity and metabolic disorders, but the structure of this signaling complex has evaded researchers for years.

Georgios Skiniotis, a faculty member at the Life Sciences Institute and assistant professor in biological chemistry at the U-M Medical School, employed electron microscopy to obtain the first picture of the interaction between leptin and its receptor.

Skiniotis also traced similarities between the leptin receptor and other receptors of the same family, which may provide insight into new targets for treatment of other hormone-related diseases.

"It is exciting not only because it might help with developing new drugs," Skiniotis said. "We now better understand the design and mechanisms of signaling through this class of receptors, which brings us to a whole new set of intriguing questions."

In the paper "Ligand-Induced Architecture of the Leptin Receptor Signaling Complex," published electronically ahead of print on Oct. 11 in Molecular Cell, Skiniotis and his co-authors explain how the receptor is formed by two hinged legs that can swivel until they encounter leptin, which binds to the legs and makes them rigid.

Once the two legs of a receptor become rigid by binding to leptin, they signal to an enzyme called the Janus kinase. A number of drugs have been studied for treatments related to the Janus kinases; inhibiting it may lead to improvement of conditions like rheumatoid arthritis, psoriasis and metabolic disorders that are linked to inflammation.

Alan Saltiel, director of the Life Sciences Institute and a widely cited researcher who works on diabetes, obesity and metabolic disorders, sees a range of possibilities in the work of Skiniotis.

"This study may help solve an important issue we've been struggling with for some time," he said. "Since leptin is a master regulator of appetite, understanding why resistance to its effects develops in obesity has been a major obstacle to discovering new drugs for obesity and diabetes. Developing a clear picture of how leptin can bind to its receptor may be the first step in overcoming leptin resistance."

Other U-M authors on the paper were Liliya Mancour and Gerwin Westfield of the Life Sciences Institute and Department of Biological Chemistry and Hikmat Daghestani, Somnath Dutta, Justin Schilling, Austin Oleskie, Jeffrey Herbstman and Steven Chou of the Life Sciences Institute.

The work in Skiniotis' lab was supported by the National Institute of Diabetes and Digestive and Kidney Diseases and the National Institute of General Medical Sciences Pharmacological Sciences Training Program. Skiniotis is a Pew Scholar of Biomedical Sciences.

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Journal Reference:

1. Liliya V. Mancour, Hikmat N. Daghestani, Somnath Dutta, Gerwin H. Westfield, Justin Schilling, Austin N. Oleskie, Jeffrey F. Herbstman, Steven Z. Chou, Georgios Skiniotis. Ligand-Induced Architecture of the Leptin Receptor Signaling Complex. Molecular Cell, 2012; DOI: 10.1016/j.molcel.2012.09.003

For many Americans, the holiday season means dealing with family members and social situations that are uncomfortable and stressful. If turning to food is your solution to feeling better, you might be setting yourself up for a heavy 2013.

"If you use food as a crutch, this time of year could be troublesome," said Stefanie Barthmare, a psychotherapist with the Methodist Weight Management Center in Houston. "Getting to the root of your problems and finding better ways to deal with them without food will help you avoid putting on extra unwanted pounds this holiday season."

Barthmare said many of us make bad decisions about food under stress because we want a distraction from what is challenging us.

"We are using food for coping and comfort — and of course, we know eating is not the answer," Barthmare said. "All the food does is cause the number on the scale to creep up, causing a whole host of problems with health and self-esteem."

The cost of obesity in the United States is more than $147 million a year with obese people paying more than 40 percent more than normal weight people for health care treatment. A Body Mass Index (BMI) of 30 or above is considered obese and more than 30 percent of American fit into that category.

"Many of us will gain anywhere from seven to 10 pounds from the middle of October through the end of the year because of all the fatty foods available at parties and other gatherings," Barthmare said. "If you're not careful those numbers could easily double very quickly."

Barthmare adds there are ways to navigate through everyday problems without resorting to food. Take a walk; call a friend, read a book. Take part in anything that gets you away from wanting to eat in times of stress.

"Join a support group where you can talk about your problems and discover positive ways to fix them without eating," Barthmare said. "It's important to interrupt patterns that send you to the pantry."

Meeting with a counselor or dietitian will help you come up with strategies to change your ways, but a lot of it depends on you, your motivation and your frame of mind.

"If it was just a matter of knowing the calorie difference between a piece of cake and broccoli, we would all be all be our ideal weight," Barthmare said. "Maintaining a healthy weight requires a disciplined approach mentally and physically. Finding a way to refrain from using food to help you feel better is the key. Unfortunately, it's complicated and there is not a one-size fits all solution."

Patients who undergo bariatric weight loss surgery may be at increased risk for substance use (drug use, alcohol use and cigarette smoking) following surgery, particularly among patients who undergo laparoscopic Roux-en-Y gastric bypass surgery who appear to be at increased risk for alcohol use following surgery, according to a report published Online First by Archives of Surgery, a JAMA Network publication.

"Studies have shown that drugs, alcohol, and food trigger similar responses in the brain and that bariatric surgery candidates whose condition has been diagnosed as binge-eating disorder (BED) display addictive personalities similar to individuals addicted to substances," the authors write as background in the study. "Therefore, alcohol and drugs (including nicotine) are likely to substitute for overeating following WLS [weight loss surgery.]"

Alexis Conason, Psy.D., of New York Obesity Nutrition Research Center, and colleagues, assessed questionnaire responses from 155 patients (132 women) who underwent weight loss surgery (WLS) and were recruited from an information session at a bariatric surgery center. Patients underwent laparoscopic Roux-en-Y gastric bypass surgery (n=100) or laparoscopic adjustable gastric band surgery (n=55). Each patient completed questionnaires to assess eating behaviors and substance use prior to the operation and at one, three, six, 12 and 24 months after surgery.

Overall, the authors found that patients reported an immediate decrease in frequency of substance use following WLS, but these improvements were not maintained by 3-month follow-up, and there was a significant increase in the frequency of substance use from the time of surgery to the 24-month follow-up.

Participants reported significant increases in the frequency of substance use (a composite of drug use, alcohol use, and cigarette smoking) 24 months following surgery. In particular, the authors found that patients reported a significant increase in the frequency of substance use from the time of surgery to 24 months after surgery, as well as significant increases from one, three, and six months to 24 months after surgery.

Additionally, patients who underwent laparoscopic Roux-en-Y gastric bypass surgery (LRYGB) reported a significant increase in the frequency of alcohol use from the time before surgery to 24 months after surgery.

"Based on the present study, undergoing RYGB surgery appears to increase the risk for alcohol use following WLS," the authors conclude. "Risks and benefits should be weighted when recommending LRYGB surgery to patients who may be at increased risk of developing problems with alcohol after WLS, such as those with a personal or family history of alcohol abuse or dependence."

New evidence reveals the possibility of mood-enhancing effects associated with some flavors, stemming at least in part from natural ingredients bearing a striking chemical similarity to valproic acid, a widely used prescription mood-stabilizing drug, scientists reported in Philadelphia. This effect joins those previously reported for chocolate, teas and some other known comfort foods.

They presented the study of more than 1,700 substances that make up the flavors of common foods at the 244^th National Meeting & Exposition of the American Chemical Society.

"Molecules in chocolate, a variety of berries and foods containing omega-3 fatty acids have shown positive effects on mood. In turn, our studies show that some commonly used flavor components are structurally similar to valproic acid," said Karina Martinez-Mayorga, Ph.D., leader of a research team that has been studying the effects of flavors on mood. She described research done while working at the Torrey Pines Institute for Molecular Studies, and now is with the Chemistry Institute at the National Autonomous University of Mexico.

Sold under brand names that include Depakene, Depakote and Stavzor, valproic acid is used to smooth out the mood swings of people with manic-depressive disorder and related conditions.

"The large body of evidence that chemicals in chocolate, blueberries, raspberries, strawberries, teas and certain foods could well be mood-enhancers encourages the search for other mood modulators in food," noted Martinez-Mayorga.

Martinez-Mayorga pointed out that the need for a broad spectrum of mood modulators is fostering research not just in the pharmaceutical industry, but in the food and beverage industries as well. Food industry research, however, focuses on less-severe mood changes. People have recognized the mood-altering properties of various foods for years. Now Martinez-Mayorga's team, and other research groups, is seeking to identify the chemical compounds that moderate mood swings, help maintain cognitive health, improve mental alertness and delay the onset of memory loss.

Her study involved use of techniques of chemoinformatics ― the application of informatic methods to solve chemical problems ― to screen the chemical structures of more than 1,700 food flavor ingredients for similarities to approved antidepressants, marketed drugs and agents with reported antidepressant activity. The main result so far in the ongoing project involves valproic acid. In the future, she said that the team plans to move from the area of analyzing the database to actually begin testing the flavor/mood hypothesis experimentally. The end result may be dietary recommendations or new nutritional supplements with beneficial mood effects, she added.

"It is important to remember that just eating foods that may improve mood is not a substitute for prescribed antidepressive drugs," Martinez-Mayorga cautioned. And for people not requiring medication, she notes that eating specific foods and living a healthful lifestyle can generally boost mood.

The scientists acknowledged funding from Robertet Flavors, Inc., and the State of Florida, Executive Officer of the Governor's Office of Tourism, Trade and Economic Development.

As adults, we know that self-control and delaying gratification are important for making healthful eating choices, portion control, and maintaining a healthy weight. However, exhibiting these skills at a young age actually may affect weight later in life. A new study scheduled for publication in The Journal of Pediatrics finds that delaying gratification longer at 4 years of age is associated with having a lower body mass index (BMI) 30 years later.

Between 1968 and 1974, 653 4-year-olds completed a delay of gratification test, in which the children were given one treat, such as a cookie or a marshmallow, and were told that they would be given a second treat if they could wait to eat the first treat for an unspecified length of time (it ended up being 15 minutes). Follow-up studies found that delaying gratification for a longer time as a preschooler was associated with adolescent academic strength, social competence, planfulness, ability to handle stress, and higher SAT scores. According to Tanya R, Schlam, PhD, from the University of Wisconsin School of Medicine and Public Health's Center for Tobacco Research and Intervention, "Interventions can improve young children's self-control, which may decrease children's risk of becoming overweight and may have further positive effects on other outcomes important to society (general health, financial stability, and a reduced likelihood of being convicted of a crime)."

A video of children trying to delay gratification can be found at http://www.youtube.com/watch?v=6EjJsPylEOY.

To further assess the adult benefits of childhood self-control, Dr. Tanya Schlam and colleagues from University of Washington, Columbia University, and University of California, Berkeley, followed-up with study participants (164 responded; 57% female), who are now in their mid-30s, to assess their current BMI (an indicator of body fat), which was cross-referenced with how they did on the delay of gratification test as children. The researchers found that each minute a child delayed gratification predicted a 0.2 decrease in adult BMI. Only 24% of the respondents were overweight and 9% were obese, which is lower than the 2008 national adult average of 34% overweight and another 34% obese.

Fortunately, self-control can be modified and improved. Because large portions and tempting, high-calorie foods usually are readily available (often more so than healthy foods), developing high self-control and ability to delay gratification, along with using other strategies and interventions, can be helpful in regulating caloric intake and achieving a healthy weight, in both children and adults.

New born human infants have the largest brains among primates, but also the highest proportion of body fat. Before birth, if the supply of nutrients from the mother through the placenta is limited or unbalanced, the developing baby faces a dilemma: should resources be allocated to brain growth, or to fat deposition for use as an energy reserve during the early months after birth?

Scientists at the University of Southampton have shown that this decision could have an effect on how fat we are as children.

In new research, published in the journal PLoS ONE on August 22, 2012), scientists at the Medical Research Council (MRC) Lifecourse Epidemiology Unit at the University, performed ultrasound scans on 381 pregnant women taking part in the Southampton Women's Survey. They measured the blood flow from the placenta to the unborn baby, and the distribution of this blood to either the liver of the baby or bypassing the liver to supply the brain and heart. This was then compared with the infant's body fatness at birth and at four years old.

The findings show that greater blood flow to the baby's liver in late pregnancy was associated with greater body fatness in the infant at birth and at age four. In contrast, lower liver blood flow and a "brain-sparing" blood flow pattern (when the blood bypasses the liver and goes to the brain) occurred when the placenta was smaller and less able to meet baby's demand for essential nutrients in the womb.

These findings were independent of an association between mother's body fatness and the body fatness of her infant.

Keith Godfrey, Professor of Epidemiology and Human Development, at the University who led the study, explains: "In our evolutionary past, the demands of a big brain have led the unborn baby to develop blood flow responses which preserve nutrient delivery to the brain when the supply of essential nutrients from the mother cannot meet the baby's requirements.

"However, having a big brain has also led to evolution of a strategy to adjust blood flow through the baby's liver, which enables the liver to produce more fat — this acts as an energy reserve, protecting brain development during periods of illness or under-nutrition in early infancy. Our data suggests that evolution of this strategy has brought with it a predisposition to obesity and later diabetes in contemporary societies with abundant nutrition in later postnatal life."

Professors Guttorm Haugen from the University of Oslo and Torvid Kiserud from the University of Bergen were part of the research team. They comment: "An interpretation of our findings is that there could be programmed effects on the liver that arise from blood flow adaptations in the womb and predispose individuals to gain excess body fat. Although further studies are needed, our findings add weight to current concerns that the current epidemic of childhood obesity and associated disorders may partly have its origins through adaptations made by the developing baby during pregnancy."

Professor Mark Hanson, Director of the University of Southampton's Human Development and Health Academic Unit, adds: "If the supply of nutrients across the placenta is inadequate or unbalanced, the unborn baby has to decide whether to prioritise fat deposition or spare brain growth — it does this by changing the amount of blood flowing to the liver and brain. A decision to increase blood flow to the liver has lasting implications for the child's body fatness.

"Transfer processes across the placenta for some nutrients such as glucose evolved in environments less affluent than those now prevalent in developed populations, and our findings additionally suggest that in circumstances of maternal obesity and nutrient excess these processes now also lead to excessive fat deposition in the womb."

"This strengthens the case for all women of reproductive age having greater access to nutritional, education and lifestyle support to reduce the risk of obesity in their children and improve the health of the next generation."

Professor Cyrus Cooper, Director of the MRC Lifecourse Epidemiology Unit comments: "This study is part of a wider body of work by the MRC Lifecourse Epidemiology Unit into how factors during pregnancy might have a long-term influence on childhood growth and development. This is a wonderful example of multi-disciplinary research using the unique clinical resource provided by the Southampton Women's Survey."

 0mYour mood for food can be changed by a restaurant's choice of music and lighting, leading to increased satisfaction and reduced calorie intake, according to a new study.

"When we did a makeover of a fast-food restaurant, we found that softer music and lighting led diners to eat 175 fewer calories and enjoy it more," said the study's lead author, Brian Wansink, professor of marketing and director of Cornell University's Food and Brand Lab.

Wansink and his co-author, Koert van Ittersum of the Georgia Institute of Technology, found that softening the lighting and music in fast-food restaurants didn't change what people ordered, but it caused them to eat 18 percent less of what they ordered — 775 calories instead of 949. They also rated the food as more enjoyable. The results are posted online in the journal Psychological Reports.

The Wansink-Ittersum study counters the popular notion that people who dine in a relaxed environment, with soft lighting and mellow music, will order more food and eat more than those in a more typical dining environment.

"These results suggest that a more relaxed environment increases satisfaction and decreases consumption," Wansink said. "This is important information for fast-food restaurants, which are often accused of contributing to obesity: Making simple changes away from brighter lights and sound-reflecting surfaces can go a long way toward reducing overeating — and increase their customers' satisfaction at the same time."