Psychological Factors Influencing Nutrition

Nutrition is considered a biological and purely physical phenomenon or necessity. However, you might be interested to know that there are several psychological factors that are associated with it as well.

Nutrition is the process of intake of food by the body for means of its survival. Different foods have different nutrients, examples of which include things like carbohydrates, healthy fats, proteins, minerals, etc. A nutritious diet is not a choice but a necessity. But the fact remains that essentially, nutrition is a purely physical process.

However, recent study conducted at newspsychology has revealed an inadvertent connection between the mind and the nutrition which is consumed by the body. These are discussed as follows.

Factors Affecting Nutrition

When we eat, we determine out choice of food based on the mood that we are in. Even the amount that we eat is determined by the same. The mood is nothing but a fragment of psychology, which is affected by external or even internal conditions. Some psychological factors which affects nutrition includes-

  • Peace- when one is at peace with themselves, then they are able to eat contentedly, to their fill, without worrying, allowing the nutrients to work in a way they are supposed to.
  • Stress- this is the polar opposite of eating when you are at peace. Oftentimes, when people are stressed, they tend to stress eat, which consists of comfort food, which is usually fatty, or harmful.

Self-confidence- this is a vital aspect of psychology and nutrition. When people make an individual feel that they are too fat or too skinny, then their eating habits change, which in turn may adversely affect their nutrition intake to a large extent.

Obese brain may thwart weight loss: Diets high in saturated fat, refined sugar may cause brain changes that fuel overconsumption

Diets high in saturated fat and refined sugar may cause changes to the brains of obese people that in turn may fuel overconsumption of those same foods and make weight loss more challenging, new research indicates. (Credit: iStockphoto/Geo Martinez)

 — "Betcha can't eat just one!" For obese people trying to lose weight, advertising slogans such as this one hit a bit too close to home as it describes the daily battle to resist high calorie foods.

But new research by Terry Davidson, director of American University's Center for Behavioral Neuroscience, indicates that diets that lead to obesity — diets high in saturated fat and refined sugar — may cause changes to the brains of obese people that in turn may fuel overconsumption of those same foods and make weight loss more challenging.

"It is a vicious cycle that may explain why obesity is so difficult to overcome," said Davidson, also a professor of psychology at AU.

Davidson recently published his research, "The Effects of a High-Energy Diet on Hippocampal-Dependent Discrimination Performance and Blood-Brain Barrier Integrity Differ for Diet-Induced Obese and Diet-Resistant Rats," in the journal Physiology & Behavior.

Fat Rats Suffer Memory Impairment, Damage to Brain's Armor

Davidson, formerly with Purdue University, focuses his research on the hippocampus — the part of the brain responsible for memory and learning.

For this study, Davidson and his team trained rats given restricted access to low-fat "lab chow" on two problems — one that tested the rats' hippocampal-dependent learning and memory abilities and one that did not. Once the training phase completed, the rats were split into two groups: one group had unlimited access to the low-fat lab chow, while the other had unlimited access to high-energy (high-fat/calorie) food.

The high-energy food was high in saturated fat (animal fats, such as those found in cheese or meat or certain plant-based fats, such as cottonseed oil and coconut oil) — considered to be the most unhealthful dietary fat as research has linked it to cardiovascular disease and certain types of cancer.

When both groups of rats were presented the problems again, the rats that became obese from the high-energy diet performed much more poorly than the non-obese rats did on the problem designed to test hippocampal-dependent learning and memory. They tested the same as the non-obese rats on the other problem.

When the researchers later examined all of the rats' blood-brain barriers (if the brain were an exclusive nightclub, the blood-brain barrier — a tight network of blood vessels protecting the brain — would be the bouncer at the door carefully policing who gets in), they found that the obese rats' blood-brain barriers had become impaired as they allowed a much larger amount of a dye that does not freely cross the blood-brain barrier into the hippocampus than did blood-brain barriers of the non-obese rats (the dye was administered to all of the rats).

Interestingly, the non-obese rats group included rats from both the low-fat lab chow group and the high-energy diet group. But this isn't a matter of some rats having a super-high metabolism that allowed them eat to large amounts of the high-energy food and remain a reasonable weight.

"The rats without blood-brain barrier and memory impairment also ate less of the high-energy diet than did our impaired rats," Davidson said. "Some rats and some people have a lower preference for high-energy diets. Our results suggest that whatever allows them to eat less and keep the pounds off also helps to keep their brains cognitively healthy."

A Vicious Cycle

The hippocampus is also responsible for suppressing memories. If Davidson's findings apply to people, it could be that a diet high in saturated fat and refined sugar impacts the hippocampus's ability to suppress unwanted thoughts — such as those about high-calorie foods, making it more likely that an obese person will consume those foods and not be able to stop at what would be considered a reasonable serving.

"What I think is happening is a vicious cycle of obesity and cognitive decline," Davidson said. "The idea is, you eat the high fat/high calorie diet and it causes you to overeat because this inhibitory system is progressively getting fouled up. And unfortunately, this inhibitory system is also for remembering things and suppressing other kinds of thought interference."

Davidson's findings are compatible with other studies finding a link between human obesity in middle age and an increased likelihood of developing Alzheimer's disease and other cognitive dementias later in life.

"We are trying to figure out that link," Davidson said. "We have compelling evidence that overconsumption of a high fat diet damages or alters the blood-brain barrier. Now we are interested in the fact that substances that are not supposed to get to the brain are getting to it because of this breakdown. You start throwing things into the brain that don't belong there, and it makes sense that brain function would be affected."

A Lifelong Battle

As evidenced by contestants of NBC's reality show "The Biggest Loser," formerly obese celebrities who undergo gastric by-pass surgery, and other numerous examples of extreme weight loss, it is possible for obese people to win the battle of the bulge. Unfortunately, the attempt to keep it off is, more often than not, a lifelong battle that requires permanent lifestyle changes. Davidson says this could be due in part to permanent changes in the brain.

"I do think it [the damage] becomes permanent, but I don't know at what point it becomes permanent," Davidson said. "Other research has found that obese people and formerly obese people have weaker hippocampal activity when consuming food than do people who have never been obese. Just because you lose the weight doesn't mean you regain the brain function. This could help explain why it is so difficult for formerly obese people to keep the weight off."


Journal Reference:

  1. Terry L. Davidson, Andrew Monnot, Adelai U. Neal, Ashley A. Martin, J. Josiah Horton, Wei Zheng. The effects of a high-energy diet on hippocampal-dependent discrimination performance and blood–brain barrier integrity differ for diet-induced obese and diet-resistant rats. Physiology & Behavior, 2012; 107 (1): 26 DOI: 10.1016/j.physbeh.2012.05.015

Many parents believe that letting young children taste alcohol discourages later use

One in four mothers believe that letting young children taste alcohol may discourage them from drinking in adolescence and 40 percent believe that not allowing children to taste alcohol will only make it more appealing. (Credit: © Septemberlegs / Fotolia)

One in four mothers believe that letting young children taste alcohol may discourage them from drinking in adolescence and 40 percent believe that not allowing children to taste alcohol will only make it more appealing, according to a new study by RTI International and the University of North Carolina at Chapel Hill.

The study, published in the Archives of Pediatrics and Adolescent Medicine, explored whether parents purposefully introduce children to alcohol at a young age and, if so, why. It also examined parenting practices that impact children's opportunity to try alcohol.

"The idea that early exposure to alcohol can discourage a child's interest in drinking has a strong foothold among some parents of elementary school aged children," said Christine Jackson, Ph.D., a social ecologist at RTI International and the study's lead author.

The study is based on data collected from interviews with 1,050 mothers and their third-grade children. The participants were recruited for a four-year intervention trial that will examine the long-term implications of children's early sipping experience.

Adult participants in the study were asked about their alcohol-specific attitudes and practices as well as their opinions on providing tastes of alcohol to their children.

At least a quarter of the mothers said allowing their children to taste alcohol would discourage their curiosity in it because they would not like the flavor and because it will remove the "forbidden fruit" appeal of it. Forty percent of the mothers interviewed felt that not allowing children to have alcohol would only increase their desire to have it.

Twenty-two percent of the mothers believed that children who taste alcohol at home with their parents would be better at resisting alcohol-related peer pressure, and 26 percent thought it would make them less likely to experiment with risky drinking in middle school.

"These findings indicate that many parents mistakenly expect that the way children drink at home, under parental supervision, will be replicated when children are with peers," Jackson said. "More research is needed to understand how parents acquire these ideas and to understand the relationship between early sipping and alcohol use in adolescence."

The children who participated in the study were asked whether they had tasted beer, wine or other drinks containing alcohol and whether their parents had ever given them a sip of alcohol. Nearly 33 percent of the children participating in the study reported having tasted beer, wine or other alcohol.

The researchers found a strong association between parents who were in favor of allowing their children to taste alcohol and children's reported alcohol use. According to the study, this finding is noteworthy because early introduction to alcohol is a primary risk factor for problem drinking during adolescence.


Journal Reference:

  1. Jackson C, Ennett ST, Dickinson DM. Letting Children Sip: Understanding Why Parents Allow Alcohol Use by Elementary School–aged Children. Archives of Pediatrics & Adolescent Medicine, 2012; DOI: 10.1001/archpediatrics.2012.1198

Obese children have less sensitive taste-buds than those of normal weight

NewsPsychology (Sep. 19, 2012) — Obese kids have less sensitive taste-buds than kids of normal weight, indicates research published online in the Archives of Disease in Childhood.

This blunted ability to distinguish all five tastes of bitter, sweet, salty, sour, and umami (savoury) may prompt them to eat larger quantities of food in a bid to register the same taste sensation, suggest the authors.

They base their findings on 94 normal weight and 99 obese children aged between 6 and 18, who were in good health and not taking any medications known to affect taste and smell.

The taste sensitivity of every child was tested using 22 “taste strips” placed on the tongue, to include each of the five taste sensations, at four different levels of intensity, plus two blank strips.

Each child was asked to refrain from eating or drinking anything other than water and not to chew gum for at least an hour before they took the two tests, which involved identifying the different tastes and their intensity.

The sum of all five taste sensations at the four different intensities allowed for a maximum score of 20, with scores ranging from two to 19.

Girls and older children were better at picking out the right tastes.

Overall, the children were best able to differentiate between sweet and salty, but found it hardest to distinguish between salty and sour, and between salty and umami.

And obese children found it significantly more difficult to identify the different taste sensations, scoring an average of 12.6 compared with an average of just over 14 clocked up by children of normal weight.

Obese children were significantly less likely to identify the individual taste sensations correctly, particularly salty, umami, and bitter.

And while both obese and normal weight children correctly identified all the differing levels of sweetness, obese kids rated three out of the four intensity levels lower than kids of normal weight.

Similarly, children of normal weight were better able to distinguish the different taste sensations, the older they were, but this trend was not seen among the obese children.

Exactly why people have differing taste perceptions is unclear, but genes, hormones, acculturation and exposure to different tastes early in life are all thought to play a part, say the authors.

But previous research indicates that heightened sensitivity to different taste sensations may help to reduce the amount of food eaten as less is required to get the same “taste hit.”

Story Source:

The above story is reprinted from materials provided by BMJ-British Medical Journal.

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

Journal Reference:

  1. Johanna Overberg, Thomas Hummel, Heiko Krude, Susanna Wiegand. Differences in taste sensitivity between obese and non-obese children and adolescents. Archives of Disease in Childhood, 2012; DOI: 10.1136/archdischild-2011-301189

Nutrient in eggs and meat may influence gene expression from infancy to adulthood

Consuming greater amounts of choline — a nutrient found in eggs and meat — during pregnancy may lower an infant's vulnerability to stress-related illnesses, such as mental health disturbances, and chronic conditions, like hypertension, later in life. (Credit: © midosemsem / Fotolia)

NewsPsychology (Sep. 20, 2012) — Just as women are advised to get plenty of folic acid around the time of conception and throughout early pregnancy, new research suggests another very similar nutrient may one day deserve a spot on the obstetrician's list of recommendations.

Consuming greater amounts of choline — a nutrient found in eggs and meat — during pregnancy may lower an infant's vulnerability to stress-related illnesses, such as mental health disturbances, and chronic conditions, like hypertension, later in life.

In an early study in The FASEB Journal, nutrition scientists and obstetricians at Cornell University and the University of Rochester Medical Center found that higher-than-normal amounts of choline in the diet during pregnancy changed epigenetic markers — modifications on our DNA that tell our genes to switch on or off, to go gangbusters or keep a low profile — in the fetus. While epigenetic markers don't change our genes, they make a permanent imprint by dictating their fate: If a gene is not expressed — turned on — it's as if it didn't exist.

The finding became particularly exciting when researchers discovered that the affected markers were those that regulated the hypothalamic-pituitary-adrenal or HPA axis, which controls virtually all hormone activity in the body, including the production of the hormone cortisol that reflects our response to stress and regulates our metabolism, among other things.

More choline in the mother's diet led to a more stable HPA axis and consequently less cortisol in the fetus. As with many aspects of our health, stability is a very good thing: Past research has shown that early exposure to high levels of cortisol, often a result of a mother's anxiety or depression, can increase a baby's lifelong risk of stress-related and metabolic disorders.

"The study is important because it shows that a relatively simple nutrient can have significant effects in prenatal life, and that these effects likely continue to have a long-lasting influence on adult life," said Eva K. Pressman, M.D., study author and director of the high-risk pregnancy program at the University of Rochester Medical Center. "While our results won't change practice at this point, the idea that maternal choline intake could essentially change fetal genetic expression into adulthood is quite novel."

Pressman, who advises pregnant women every day, says choline isn't something people think a lot about because it is already present in many things we eat and there is usually no concern of choline deficiency. Though much more research has focused on folate — functionally very similar to choline and used to decrease the risk of neural tube defects like spina bifida — a few very compelling studies sparked her interest, including animal studies on the role of choline in mitigating fetal alcohol syndrome and changing outcomes in Down syndrome.

A long-time collaborator with researchers at Cornell, Pressman joined a team led by Marie Caudill, Ph.D., R.D., professor in the Division of Nutritional Sciences at Cornell, in studying 26 pregnant women in their third trimester who were assigned to take 480 mg of choline per day, an amount slightly above the standard recommendation of 450 mg per day, or about double that amount, 930 mg per day. The choline was derived from the diet and from supplements and was consumed up until delivery.

The team found that higher maternal choline intake led to a greater amount of DNA methylation, a process in which methyl groups — one carbon atom linked to three hydrogen atoms — are added to our DNA. Choline is one of a handful of nutrients that provides methyl groups for this process. The addition of a single methyl group is all it takes to change an individual's epigenome.

Measurements of cord blood and samples from the placenta showed that increased choline, via the addition of methyl groups, altered epigenetic markers that govern cortisol-regulating genes. Higher choline lessened the expression of these genes, leading to 33 percent lower cortisol in the blood of babies whose mom's consumed 930 mg per day.

Study authors say the findings raise the exciting possibility that choline may be used therapeutically in cases where excess maternal stress from anxiety, depression or other prenatal conditions might make the fetal HPA axis more reactive and more likely to release greater-than-expected amounts of cortisol.

While more research is needed, Caudill says that her message to pregnant women would be to consume a diet that includes choline rich foods such as eggs, lean meat, beans and cruciferous vegetables like broccoli. For women who limit their consumption of animal products, which are richer sources of choline than plant foods, she adds that supplemental choline may be warranted as choline is generally absent in prenatal vitamin supplements.

"One day we might prescribe choline in the same way we prescribe folate to all pregnant women," notes Pressman, the James R. Woods Professor in the Department of Obstetrics and Gynecology. "It is cheap and has virtually no side effects at the doses provided in this study. In the future, we could use choline to do even more good than we are doing right now."

In addition to Pressman and Caudill, several scientists and clinicians from the Division of Nutritional Science and the Statistical Consulting Unit at Cornell and the Cayuga Medical Center in Ithaca, N. Y., participated in the research. The study was funded by the Egg Nutrition Center, the National Cattlemen's Beef Association, the Nebraska Beef Council, the U.S. Department of Agriculture and the President's Council of Cornell Women. The funding sources had no role in the study design, interpretation of the data, or publication of the results.


Journal Reference:

  1. X. Jiang, J. Yan, A. A. West, C. A. Perry, O. V. Malysheva, S. Devapatla, E. Pressman, F. Vermeylen, M. A. Caudill. Maternal choline intake alters the epigenetic state of fetal cortisol-regulating genes in humans. The FASEB Journal, 2012; 26 (8): 3563 DOI: 10.1096/fj.12-207894

You have to eat, except when you're not hungry

 When compared to their normal-weight siblings, overweight and obese children ate 34 percent more calories from snack foods even after eating a meal, reports a University of Pennsylvania School of Nursing researcher in The American Journal of Clinical Nutrition. That can be enough calories, if sustained over time, to continue excess weight gain.

In a study of 47 same-sex sibling pairs, the research showed that, even after eating a meal they enjoyed until they were full, overweight and obese children were more prone to overeating when presented with desirable snack foods than their normal-weight siblings.

The study also showed that normal-weight siblings ate less of the meal than their overweight siblings when provided with a calorie-dense appetizer just before the meal. In comparison, overweight and obese siblings did not lessen the amount they ate at the meal enough to offset the additional calories from the appetizer.

"The overweight and obese siblings showed an impaired ability to adjust for calorie differences and consumed more snacks even when satiated," said lead author Tanja Kral, PhD, an assistant professor at Penn Nursing. "These findings suggest some children are less responsive to their internal cues of hunger and fullness and will continue eating even when full."

This inability may be inherited and exacerbated by an environment that offers large portions of desirable foods, said Dr. Kral, explaining that the full siblings in the study were more similar in their eating behaviors more commonly ate more than the half-siblings, suggesting a genetic influence underlying these traits.

In the study, siblings ate a standardized dinner of pasta with tomato sauce, broccoli, unsweetened applesauce, and two percent milk once a week for three weeks. When presented with desirable post-meal snack foods, the overweight and obese siblings ate an average of 93 calories more than their normal-weight siblings. This additional calorie intake over time is considered enough to lead to excess weight gain.

"These findings may represent a behavioral inclination for obesity in children," Dr. Kral said. "Future studies should test whether teaching children to focus on internal satiety cues and structuring the home food environment in a healthy way may prevent at-risk children from overeating."

Journal Reference:

  1. T. V. Kral, D. B. Allison, L. L. Birch, V. A. Stallings, R. H. Moore, M. S. Faith. Caloric compensation and eating in the absence of hunger in 5- to 12-y-old weight-discordant siblings. American Journal of Clinical Nutrition, 2012; 96 (3): 574 DOI: 10.3945/ajcn.112.037952

Gut reaction: Morality in food choice

Personal ethics can be a powerful motivator when it comes to food choices. (Credit: iStockphoto)

We've all heard the saying, "you are what you eat." It turns out the old adage might be true on more than just a physical level. The food you choose may also reflect your personal ethics.

Whether we like it or not, buying food has moral implications ranging from environmental sustainability to social justice to animal welfare. Was the apple you ate at lunch grown in your state, or even your country? How much land and water did it take to produce? Was the farmer who picked it making a fair wage?

Several researchers at Arizona State University are examining the ethical aspects of food production and consumption. They are helping consumers navigate the maze of moral choices involved in filling their plates and their bellies. And they are finding that being morally mindful can lead to better nutrition, as well.

Ethical eats

Where does a chicken or an avocado start its life before making its way to the grocery store? Joan McGregor studies food production and the ethical concerns it raises. One of these, of course, is environmental sustainability.

"We all talk about water, we talk about energy, but we sort of forget that food is a huge consumer of resources," says McGregor, who teaches philosophy in the School of Philosophical, Historical, and Religious Studies in ASU's College of Liberal Arts and Sciences.

Sustainability can be tricky to measure, however. For example, most people think shopping locally reduces their carbon footprint. But depending on the type of food, that might not be the case at all. Some foods are more resource intensive than others and generate more carbon during production, even if they don't get transported very far.

Social issues come into play, as well. Buying locally means supporting a local farmer. You might think that's an ethical no-brainer, but consider this: Before the local food movement was all the rage, socially conscious consumers chose fair-trade products (often produced in other countries) because they guaranteed the farmer decent working conditions and a living wage.

"If you're just thinking about welfare or doing good in the world, you might be doing better by buying from some Guatemalan farmer than buying from some Queen Creek farmer," McGregor says. This is just one of many ethical conundrums in the business of food production.

The meat industry presents another set of issues, such as poor treatment of animals on factory farms, a negative impact on the environment and health concerns over hormone and antibiotic use.

"It's more than just 'should I eat meat or not?' It's a question of the way we produce meat. Right now it is incredibly inhumane, but it's also incredibly unsustainable," McGregor says. The major byproducts of meat production are waste and toxins that can be hazardous to human health and to the health of the environment.

Some people substitute seafood for meat. But is fish really more healthy and sustainable? It depends on the type you choose, says Leah Gerber, a conservation biologist in the School of Life Sciences in ASU's College of Liberal Arts and Sciences.

Fishing for answers

Gerber recently co-authored a study examining the healthfulness and sustainability of more than 300 different species of fish. To measure healthfulness, she looked at omega-3 fatty acids. Research has shown that these fats can improve cardiovascular health and boost mood.

Gerber also determined which species had the highest mercury levels, since too much mercury can damage the human nervous system. To gage sustainability, Gerber considered factors like exploitation of the species population and carrying capacity of the ocean environment.

Her analysis found that very large, long-lived fish like the bluefin tuna are typically high in mercury, low in omega-3's and unsustainable. Mercury is a pollutant that gets into lakes, rivers and oceans. Fish and other marine life unwittingly eat it up. As larger animals eat the smaller ones, the mercury "bioaccumulates," or collects in increasing quantities. Large fish high on the food chain contain the highest levels.

Large fish also take longer to sexually mature. As a result, it is difficult to recover their populations when they are overexploited. In general, the least healthful species are also the least sustainable. In addition to bluefin, these include Atlantic cod, swordfish and Spanish mackerel.

Fortunately, fish that are better for your health are also the most sustainable. These include Pacific cod, Alaskan pollock and black rockfish.

Why worry about sustainable fishing? "We need to take care of the ocean and effectively manage fisheries if we want to eat fish in the future," Gerber says, adding that most fish stocks in the world are over-harvested. Global climate change has also added to the problem. As greenhouse gases in the atmosphere increase, oceans absorb more carbon dioxide, making them acidic and less hospitable to many fish species.

"There's this perception that the ocean is inexhaustible — we can just dump stuff in it and exploit it — but it's not," Gerber says.

Follow your gut

Gerber believes we have an ethical obligation to take care of the environment. By approaching food ethically, we may also benefit our own health. That's because our moral views affect us on an emotional, "gut" level that may have a stronger influence on our behavior than facts.

Consider, for example, a practicing Muslim who doesn't eat pork. She has avoided pork products all her life, and as an adult, doesn't think twice about passing up bacon and pork chops. A gut reaction to the food makes it undesirable to her. It's the same feeling an Orthodox Jew who follows dietary kosher laws might have about eating meat and cheese together.

"These violations of ethical mores are felt to be dirty, disgusting or not sacred in some way," says Eric Hekler, an assistant professor in the School of Nutrition and Health Promotion at ASU.

These kinds of reactions aren't always religious in nature. Some vegetarians, for example, say they became disgusted by meat after reading about conditions in meat packing plants in Upton Sinclair's The Jungle, or watching documentaries about how animals are treated on factory farms.

Hekler is interested in tapping into human morals to produce healthier eating habits. In a study published in the American Journal of Preventive Medicine, he and his colleagues Tom Robinson and Christopher Gardner found that students at Stanford who took a class examining the ethics of food production made more healthy food choices by the end of the class than students who took courses on human health.

"We got people to eat better by focusing more on the environmental and sustainability aspects, rather than focusing just on a message of health," Hekler says. Surveys of the students revealed that those who took his food and society class ate more vegetables and less fatty meat and dairy by the end of the class than students enrolled in the human health courses.

These results suggest that appealing to a person's morals, rather than just giving them facts, could be an effective way to change behavior. In ongoing research, Hekler and his ASU colleagues Punam Ohri-Vachaspathi and Christopher Wharton have gathered survey data from about 600 ASU students to explore ways of linking healthful eating with morality.

Why tap into morals and emotion to change eating habits and behavior? If someone wants to lose weight or improve their health, there is an abundance of information online about the benefits of physical activity and a diet rich in fruits and vegetables. But as obesity rates rise, it's clear that facts alone aren't enough.

That could be because ultimately, our gut reactions are stronger than our rational thoughts. Hekler explains this concept with a metaphor first developed by Jonathan Haidt, whose Moral Foundations Theory is a core inspiration for Hekler's research. Haidt says your intuitive, emotional response is like an elephant, while rational thought is the rider.

"There's this intuitive part of you, which is the elephant underneath, and if he really wants those peanuts, the rider can stop him for a short time but will eventually get overwhelmed and tired," Hekler says. He hopes with further research to develop an intervention package that will effectively target the elephant.

Technical support

Even if your gut craves humanely and sustainably produced food, the choices are rarely black and white. There are always tradeoffs, like in McGregor's example of buying food locally.

"It's very difficult to just say, 'this is the right thing.' I think that presupposes a model of morality that's too simplistic," McGregor says. But the more information we have available, the better off we are making choices that reflect our values. That's why McGregor wants to create a smartphone application or online tool to help consumers sort through the moral factors associated with the food they eat.

"I like to believe that people want to do the right thing, but don't always know which option is the right thing," McGregor says. For example, many people would pay a little more for a product if they could check with an app and find out that the alternative was manufactured by a child in unsafe working conditions.

Hekler also wants to use technology to promote healthier behavior. He is analyzing a series of smartphone apps that encourage users to stay active. The apps were first developed at Stanford University with his former mentor and co-director for the project, Abby King.

One app is numbers-based. It records and displays the amount of time users spend being active versus sedentary each day. But the other two apps are focused more on emotions and social relationships. One of them uses a live wallpaper with an animated bird that flies and becomes more lively as the smartphone owner moves around throughout the day. The app employs operant conditioning principles, Hekler explains, rewarding the user with a happy bird as he or she performs the desired behavior — physical activity.

"As I walk faster, this bird flies faster, is happier and more playful, and sings me songs. Every time I open the phone, I get a subtle nudge about how active I'm being," Heckler says.

The goal is to provoke an emotional reaction in users, motivating them to walk and move more throughout the day. Preliminary results reported at a recent conference of the Society of Behavioral Medicine found that the emotion-based and social-based apps produced favorable results relative to a control group, but the number-based one did not.

Researchers hope that targeting people's morals rather than their rational thoughts will be an effective way to promote healthy and ethical choices.

"We need to connect people's values to their food choices," McGregor says. "That means people need to have access to certain kinds of information that ties food decisions to values about the environment, animals and social justice."

Read more about Gerber's fish study:

The School of Philosophical, Historical, and Religious Studies and the School of Life Sciences are academic units of the College of Liberal Arts and Sciences at Arizona State University.

Like humans, monkeys can make irrational decisions when making choices

A monkey chooses between groups of objects. (Credit: Citation: Kralik JD, Xu ER, Knight EJ, Khan SA, Levine WJ (2012) When Less Is More: Evolutionary Origins of the Affect Heuristic. PLoS ONE 7(10): e46240.doi:10.1371/journal.pone.0046240)

When making decisions about the value of an assortment of different objects, people approximate an average overall value, which though frequently useful can lead to apparently irrational decision-making. A new study published Oct 3 in PLOS ONE by Jerald Kralik and colleagues at Dartmouth College shows for the first time that non-human primates also make similar 'irrational' choices based on approximation.

In the study, researchers found that rhesus monkeys preferred a highly-valued food item (a fruit) alone to the identical item paired with a food of positive but lower value (fruit and a vegetable).

The researchers suggest that this behavior is similar to what has been seen in previous studies with humans, where participants rated a 24-piece dinnerware set more highly than one with the same 24 pieces, plus 16 more pieces of which nine were broken.

According to the authors, decision-making processes in humans and other primates have evolved towards reducing the complexity in choices between large groups of assorted items, which may result in such irrational choices.

"People often judge a group — of valuables, of foods, of other people — by its average rather than by the sum of its parts. Our study shows that monkeys appear to do the same thing, which suggests that both monkeys and people inherited a particular way of simplifying the world around us, making choices easier, sometimes at the expense of 'rationality'" says Kralik.


Journal Reference:

  1. Jerald D. Kralik, Eric R. Xu, Emily J. Knight, Sara A. Khan, William J. Levine. When Less Is More: Evolutionary Origins of the Affect Heuristic. PLoS ONE, 2012; 7 (10): e46240 DOI: 10.1371/journal.pone.0046240

Moderate alcohol consumption may increase risk of atrial fibrillation in people with heart disease

Moderate alcohol consumption increases the risk of atrial fibrillation in older people with heart disease or advanced diabetes, says a study by McMaster researchers.

"Moderate alcohol intake, with or without episodic binge drinking, is associated with an increased incidence of atrial fibrillation in older and high risk cardiovascular disease or diabetes patients," said Dr. Koon Teo, an author of the study and a professor of medicine at the Michael G. DeGroote School of Medicine at McMaster University. "Among moderate drinkers, the effect of binge drinking on atrial fibrillation risk is similar to that of habitual heavy drinking."

The study was published October 1 by the Canadian Medical Association Journal (CMAJ). Atrial fibrillation, or an irregular heartbeat, is a concern because it increases the risk of stroke.

The findings come from a large study involving more than 30,000 individuals 55 years or older from 40 countries who had a history of cardiovascular disease or advanced diabetes with organ damage. Data came from the clinical trials which followed participants for four and half years.

Moderate alcohol consumption was measured as one to 14 drinks a week for women and one to 21 drinks a week for men. Binge drinking was classified as five or more drinks a day.

The incidence rate of atrial fibrillation rose to 6.3% of the low intake group, 7.8% in the moderate and 8.3% in the high intake groups. The increase in atrial fibrillation cases linked to higher alcohol consumption was found in each age group.

The report said that since moderate drinking is common for more than a third of the population, these findings suggest the effect of increased alcohol consumption, even in moderate amounts, on atrial fibrillation risk in patients with pre-existing cardiovascular disease may be considerable.

Limited data from other studies indicates that binge drinking in healthy people may increase the risk of atrial fibrillation, although moderate drinking in healthy individuals does not appear to be linked to increased risk.

"Recommendations made about the protective effects of moderate alcohol intake in patients at high risk of cardiovascular disease may need to be tempered with these findings," the report said.

Why wine and tea pair so well with a meal: It's all in the mouthfeel

Of course a nice glass of wine goes well with a hearty steak, and now researchers who study the way food feels in our mouths think they may understand why. (Credit: © / Fotolia)

Of course a nice glass of wine goes well with a hearty steak, and now researchers who study the way food feels in our mouths think they may understand why that is: The astringent wine and fatty meat are like the yin and yang of the food world, sitting on opposite ends of a sensory spectrum.

The findings, reported in the October 9th issue of Current Biology, a Cell Press publication, offer a whole new definition of the balanced meal. They also offer a new way of thinking about our eating habits, both good and bad.

"The mouth is a magnificently sensitive somatosensory organ, arguably the most sensitive in the body," said Paul Breslin of Rutgers University and the Monell Chemical Senses Center. "The way foods make our mouths feel has a great deal to do with what foods we choose to eat."

It might explain the appeal of salad dressings, with their characteristic acids and oils, for example. Think also of the pink folds of ginger on the sides of our sushi plates or the soda with our burgers and fries.

The researchers knew that astringent wines feel rough and dry in our mouths. Fats, on the other hand, are slippery. There was the notion that the two might oppose each other, but it wasn't quite clear how that might really work. After all, the astringents we consume are only weakly astringent.

Breslin, Catherine Peyrot des Gachons, and colleagues now show that weakly astringent brews — in this case containing grape seed extract, a green tea ingredient, and aluminum sulfate — build in perceived astringency with repeated sipping. When paired with dried meat, those astringent beverages indeed counter the slippery sensation that goes with fattiness.

This natural tendency for seeking balance in our mouths might have benefits for maintaining a diversity of foods in our diet, Breslin says.

"The opposition between fatty and astringent sensations allows us to eat fatty foods more easily if we also ingest astringents with them," he says.

As an aside, Breslin adds, fresh seeds and nuts could have a certain sort of appeal. "These foods come both with their own fats and astringents in one package, so they may be self-balancing."


Journal Reference:

  1. Catherine Peyrot des Gachons, Emi Mura, Camille Speziale, Charlotte J. Favreau, Guillaume F. Dubreuil, Paul A.S. Breslin. Opponency of astringent and fat sensations. Current Biology, 2012; 22 (19): R829 DOI: 10.1016/j.cub.2012.08.017