Got food cravings? What's living in your gut may be responsible

April 20, 2022

Science Daily/University of Pittsburgh

Eggs or yogurt, veggies or potato chips? We make decisions about what to eat every day, but those choices may not be fully our own. New University of Pittsburgh research on mice shows for the first time that the microbes in animals' guts influence what they choose to eat, making substances that prompt cravings for different kinds of foods.

"We all have those urges -- like if you ever you just feel like you need to eat a salad or you really need to eat meat," said Kevin Kohl, an assistant professor in the Department of Biology in the Kenneth P. Dietrich School of Arts and Sciences. "Our work shows that animals with different compositions of gut microbes choose different kinds of diets."

Despite decades of speculation by scientists about whether microbes could influence our preferred diets, the idea has never been directly tested in animals bigger than a fruit fly. To explore the question, Kohl and his postdoc Brian Trevelline (A&S '08), now at Cornell University, gave 30 mice that lacked gut microbes a cocktail of microorganisms from three species of wild rodents with very different natural diets.

The duo found that mice in each group chose food rich in different nutrients, showing that their microbiome changed their preferred diet. The researchers published their work today in the Proceedings of the National Academy of Sciences.

While the idea of the microbiome affecting your behavior may sound far-fetched, it's no surprise for scientists. Your gut and your brain are in constant conversation, with certain kinds of molecules acting as go-betweens. These byproducts of digestion signal that you've eaten enough food or maybe that you need certain kinds of nutrients. But microbes in the gut can produce some of those same molecules, potentially hijacking that line of communication and changing the meaning of the message to benefit themselves.

One such messenger will be familiar to anyone who's had to take a nap after a turkey dinner: tryptophan.

"Tryptophan is an essential amino acid that's common in turkey but is also produced by gut microbes. When it makes its way to the brain, it's transformed into serotonin, which is a signal that's important for feeling satiated after a meal," Trevelline said. "Eventually that gets converted into melatonin, and then you feel sleepy."

In their study, Trevelline and Kohl also showed that mice with different microbiomes had different levels of tryptophan in their blood, even before they were given the option to choose different diets -- and those with more of the molecule in their blood also had more bacteria that can produce it in their gut.

It's a convincing smoking gun, but tryptophan is just one thread of a complicated web of chemical communication, according to Trevelline. "There are likely dozens of signals that are influencing feeding behavior on a day-to-day basis. Tryptophan produced by microbes could just be one aspect of that," he said. It does, however, establish a plausible way that microscopic organisms could alter what we want to eat -- it's one of just a few rigorous experiments to show such a link between the gut and the brain despite years of theorizing by scientists.

There's still more science to do before you should start distrusting your food cravings, though. Along with not having a way to test the idea in humans, the team didn't measure the importance of microbes in determining diet compared to anything else.

"It could be that what you've eaten the day before is more important than just the microbes you have," Kohl said. "Humans have way more going on that we ignore in our experiment. But it's an interesting idea to think about."

And it's just one behavior that microbes could be tweaking without our knowledge. It's a young field, Kohl points out, and there's still lots to learn.

"I'm just constantly amazed at all of the roles we're finding that microbes play in human and animal biology," Kohl said.

https://www.sciencedaily.com/releases/2022/04/220420151540.htm

New study reveals that healthy plant-based diets are associated with a lower risk of developing diabetes

April 10, 2022

Science Daily/Diabetologia

New research published in Diabetologia (the journal of the European Association for the Study of Diabetes [EASD]) finds that the consumption of healthy plant-based foods, including fruits, vegetables, nuts, coffee, and legumes, is associated with a lower risk of developing type 2 diabetes (T2D) in generally healthy people and support their role in diabetes prevention.

The study was conducted by Professor Frank Hu and colleagues at the Department of Nutrition, Harvard T.H. Chan School of Public Health, Boston, MA, USA, and aimed to identify the metabolite profiles related to different plant-based diets and investigate possible associations between those profiles and the risk of developing T2D.

A metabolite is a substance used or produced by the chemical processes in a living organism and includes the vast number of compounds found in different foods as well as the complex variety of molecules created as those compounds are broken down and transformed for use by the body. Differences in the chemical makeup of foods means that an individual's diet should be reflected in their metabolite profile. Recent technological advances in the field of high-throughput metabolomics profiling have ushered in a new era of nutritional research. Metabolomics is defined as the comprehensive analysis and identification of all the different metabolites present within a biological sample.

Over 90% of diabetes cases are the type 2 form, and the condition poses a major threat to health around the world. Global prevalence of the disease in adults has more than tripled in less than two decades, with cases increasing from around 150 million in 2000 to over 450 million in 2019 and projected to rise to around 700 million in 2045.

The global health burden of T2D is further increased by the numerous complications arising from the disease, both macrovascular, such as cardiovascular disease, and microvascular, which damage the kidneys, the eyes, and the nervous system. The diabetes epidemic is primarily caused by unhealthy diets, having overweight or obesity, genetic predisposition, and other lifestyle factors such as a lack of exercise. Plant-based diets, especially healthy ones rich in high quality foods such as whole grains, fruits, and vegetables, have been associated with a lower risk of developing T2D but the underlying mechanisms involved are not fully understood.

The team conducted an analysis of blood plasma samples and dietary intake of 10,684 participants from three prospective cohorts (Nurses' Health Study, Nurses' Health Study II and Health Professionals Follow-up Study). Participants were predominantly white, middle-aged (mean age 54 years), and with a mean body mass index (BMI) of 25.6kg/m2.

Study participants completed food frequency questionnaires (FFQs) which were scored according to their adherence to three plant-based diets: an overall Plant-based Diet Index (PDI), a healthy Plant-based Diet Index (hPDI), and an Unhealthy Plant-Based Diet Index (uPDI). Diet indices were based on that individual's intake of 18 food groups: healthy plant foods (whole grains, fruits, vegetables, nuts, legumes, vegetable oils, and tea/coffee); unhealthy plant foods (refined grains, fruit juices, potatoes, sugar-sweetened beverages, and sweets/desserts); and animal foods (animal fats, dairy, eggs, fish/seafood, meat, and miscellaneous animal-based foods). The team distinguished between healthy and unhealthy plant foods according to their association with T2D, cardiovascular disease, certain cancers, and other conditions, including obesity and high blood pressure.

The researchers tested blood samples taken back in late 1980s and 1990s in the early phase of the three studies mentioned above to create metabolite profile scores for the participants, and any cases of incident T2D during the follow-up period of the study were recorded. Analyses of these data together with the diet index scores enabled the team to find any correlations between metabolite profile, diet index, and T2D risk.

The study found that compared with participants who did not develop T2D, those who were diagnosed with the disease during follow-up had a lower intake of healthy plant-based foods, as well as lower scores for PDI and hPDI. In addition, they had a higher average BMI, and were more likely to have high blood pressure and cholesterol levels, use blood pressure and cholesterol drugs, have a family history of diabetes, and be less physically active.

The metabolomics data revealed that plant-based diets were associated with unique multi-metabolite profiles, and that these patterns differed significantly between the healthy and unhealthy plant-based diets. In addition, metabolite profile scores for both the overall plant-based diet and the healthy plant-based diet were inversely associated with incident T2D in a generally healthy population, independent of BMI, and other diabetes risk factors, while no association was observed for the unhealthy plant-based diet. As a result, higher metabolite profile scores for PDI and hPDI indicated both closer adherence to those diets and having a lower risk of developing T2D.

Further analysis revealed that after adjusting for levels of trigonelline, hippurate, isoleucine, a small set of triacyglycerols (TAGs), and several other intermediate metabolites, the association between plant-based diets and T2D largely disappeared, suggesting that they might play a key role in linking those diets to incident diabetes. Trigonelline, for example, is found in coffee and has demonstrated beneficial effects on insulin resistance in animal studies, while higher levels of hippurate are associated with better glycaemic control, enhanced insulin secretion and lower risk of T2D. The team suggest that these metabolites could be investigated further and may provide mechanistic explanations of how plant-based diets can have a beneficial effect on T2D risk.

Professor Hu explains: "While it is difficult to tease out the contributions of individual foods because they were analysed together as a pattern, individual metabolites from consumption of polyphenol-rich plant foods like fruits, vegetables, coffee, and legumes are all closely linked to healthy plant-based diet and lower risk of diabetes."

The authors conclude: "Our findings support the beneficial role of healthy plant-based diets in diabetes prevention and provide new insights for future investigation…our findings regarding the intermediate metabolites are at the moment intriguing but further studies are needed to confirm their causal role in the associations of plant-based diets and the risk of developing type 2 diabetes."

Since they only collected blood samples at one point in time, the authors also believe that long-term repeated metabolomics data are needed to understand how dietary changes relate to changes in metabolome, thereby influencing T2D risk.

https://www.sciencedaily.com/releases/2022/04/220410110753.htm

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How sugar promotes inflammation

March 22, 2022

Science Daily/University of Würzburg

People who consume sugar and other carbohydrates in excess over a long period of time have an increased risk of developing an autoimmune disease. In affected patients, the immune system attacks the body's own tissue and the consequences are, for example, chronic inflammatory bowel diseases such as Crohn's disease and ulcerative colitis, type 1 diabetes and chronic inflammation of the thyroid gland.

New targets for therapy

The underlying molecular mechanisms that promote autoimmune diseases are multilayered and complex. Now, scientists at the Julius Maximilians University of Würzburg (JMU) have succeeded in deciphering new details of these processes. Their work support the notion that excessive consumption of glucose directly promotes the pathogenic functions of certain cells of the immune system and that, conversely, that a calorie-reduced diet can have a beneficial effect on immune diseases. Based on these findings, they also identified new targets for therapeutic interventions: A specific blockade of glucose-depended metabolic processes in these immune cells can suppress excessive immune reactions.

Dr. Martin Väth is responsible for the study, which has now been published in the journal Cell Metabolism. He is a junior research group leader at the Institute of Systems Immunology -- a Max Planck research group under the umbrella of JMU that focusses on the interplay of the immune system with the organism. Collaborators from Amsterdam, Berlin, Freiburg and Leuven were also involved in this study.

Glucose transporter with a side job

Martin Väth explains: "Immune cells need large amounts of sugar in the form of glucose to perform their tasks. With the help of specialized transporters at their cell membrane, they can take up glucose from the environment." Together with his team, Väth has showed that a specific glucose transporter -- scientifically named GLUT3 -- fulfills additional metabolic functions in T cells besides the generating energy from sugar.

In their study, the scientists focused on a group of cells of the immune system that have not been known for very long: T helper cells of type 17, also called Th17 lymphocytes, which play an important role in regulating (auto-) inflammatory processes.

"These Th17 cells express lots of GLUT3 protein on their cell surface," Väth explains. Once taken up, glucose is readily converted to citric acid in the mitochondria before it is metabolized into acetyl-coenzyme A (acetyl-CoA) in the cytoplasm. Acetyl-CoA is involved in numerous metabolic processes, including the biosynthesis of lipids.

Influence on proinflammatory genes

However, acetyl-CoA fulfills additional functions in inflammatory Th17 cells. Väth and his team showed that this metabolic intermediate can also regulate the activity of various gene segments. Thus, glucose consumption has a direct influence on the activity of proinflammatory genes.

According to the researchers, theses new findings pave the way for the development of targeted therapy of autoimmune diseases. For example, blocking GLUT3-dependent synthesis of acetyl-CoA by the dietary supplement hydroxycitrate, which is used to treat obesity, can mitigate the pathogenic functions of Th17 cells and reduce inflammatory-pathological processes. The so-called "metabolic reprogramming" of T cells opens new possibilities to treat autoimmune diseases without curtailing protective immune cell functions.

https://www.sciencedaily.com/releases/2022/03/220322122836.htm

People with diabetes who eat less processed food at night may live longer

Study finds eating carbs earlier in the day is linked to better heart health

March 15, 2022

Science Daily/The Endocrine Society

The time of day that people with diabetes eat certain foods may be just as important to their well-being as portion size and calories, according to a new study published in the Endocrine Society's Journal of Clinical Endocrinology and Metabolism.

Mealtimes should be in line with the biological clock -- a natural, internal process that regulates the sleep-wake cycle and repeats every 24 hours. Health outcomes for people with diabetes may be improved if certain foods are eaten at different times of the day.

"We observed that eating potatoes in the morning, whole grains in the afternoon, greens and milk in the evening and less processed meat in the evening was associated with better long-term survival in people with diabetes," said Qingrao Song, M.D., of Harbin Medical University in Harbin, China. "Nutritional guidelines and intervention strategies for diabetes should integrate the optimal consumption times for foods in the future."

The researchers analyzed data from 4,642 people with diabetes from the National Health and Nutrition Examination Survey to determine their risk of dying from heart disease. They found people with diabetes who ate potatoes or starchy vegetables in the morning, whole grains in the afternoon, and dark vegetables such as greens and broccoli and milk in the evening were less likely to die from heart disease. Those who ate a lot of processed meat in the evening were more likely to die from heart disease.

https://www.sciencedaily.com/releases/2022/03/220315095028.htm

Chef’s kiss: Research shows healthy home cooking equals a healthy mind

New research has found being confident in the kitchen is not only good for your taste buds: it’s also good for your mental health

March 21, 2022

Science Daily/Edith Cowan University

New research from Edith Cowan University (ECU) has found being confident in the kitchen is not only good for your taste buds: it's also good for your mental health.

The study follows ECU's successful partnership with The Good Foundation and Jamie's Ministry of Food initiative, with a mobile food kitchen providing cooking classes in the community as well as at the University's Perth and SW campuses, throughout 2016 to 2018.

In total, 657 participants undertook the seven-week healthy cooking course.

At the same time, ECU Institute for Nutrition Research academics measured the program's effect on participants' cooking confidence and self-perceived mental health, as well as their overall satisfaction around cooking and diet-related behaviours.

Researchers found those who participated in the program saw significant improvements in general health, mental health and subjective vitality immediately after the program which remained six months after completing the course, when compared to the study's control group.

Improvements in cooking confidence, the ability to easily change eating habits and overcome lifestyle barriers to healthy eating were also reported.

Lead researcher Dr Joanna Rees said the study showed the importance of diet for mental health.

"Improving people's diet quality can be a preventive strategy to halt or slow the rise in poor mental health, obesity and other metabolic health disorders," she said.

"Future health programs should continue to prioritise the barriers to healthy eating such as poor food environments and time restrictions, whilst placing greater emphasis on the value of healthy eating via quick and easy home cooked meals, rich in fruit and vegetables and avoiding ultra-processed convenience foods."

It's not just the food 

The Institute has previously found a link between eating more fruits and vegetables, and improved longer term mental health in a larger study collecting more sophisticated dietary data, implying the participants in the current study may have felt better due to improved diet.

However, the study showed participants' mental health improved despite their reported diet not being found to have changed after completing the program.

Also, the mental health benefits were equal among participants who were overweight or obese, and those in a healthy weight range.

"This suggests a link between cooking confidence and satisfaction around cooking, and mental health benefits," Dr Rees said.

Who benefits most? 

The study also revealed cooking remains a highly gendered task.

At the start of the program, 77 per cent of participants who identified as female claimed to be confident about cooking, compared to just 23 per cent of those who identified as male.

But at the end of the program, cooking confidence and cooking skills were equal across both counterparts.

"This change in confidence could see change to the household food environment by reducing the gender bias and leading to a gender balance in home cooking," Dr Rees said.

"This in turn may help to overcome some of the barriers presented by not knowing how to cook, such as easing the time constraints which can lead to readymade meals which are high in energy but low in nutritional value."

'How a 7-Week Food Literacy Program Affects Cooking Confidence and Mental Health: Findings of a Quasi-Experimental Controlled Intervention Trial' was published inFrontiers in Nutrition.

https://www.sciencedaily.com/releases/2022/03/220321091919.htm

Brain differences in children with binge eating disorder

March 15, 2022

Science Daily/Keck School of Medicine of USC

Brain scans of children ages 9-10 with a type of eating disorder that causes uncontrollable overeating showed differences in gray matter density compared to their unaffected peers, according to a USC-led study.

Binge eating disorder, which affects about 3-5% of the U.S. population, is characterized by frequent episodes of eating large amounts of food and a sense of having no control over the behavior. The study's findings suggest that abnormal development in the brain's centers for reward and inhibition may play a role.

The recently published study is available online in the journal Psychiatry Research.

"In children with binge eating disorder, we see abnormality in brain development in brain regions specifically linked to reward and impulsivity, or the ability to inhibit reward," said lead author Stuart Murray, Della Martin Associate Professor of Psychiatry and the Behavioral Sciences at the Keck School of Medicine of USC, where he serves as director of the Eating Disorders Program.

"These kids have a very, very heightened reward sensitivity, especially toward calorically dense, high-sugar foods. The findings underscore the fact that this is not a lack of discipline for these kids."

Pandemic saw increase in eating disorders among young people

Experts say eating disorders in young people soared during the pandemic, along with steep increases in hospitalizations. Social isolation, stress, disruption of routine and a social media-fueled quest for perfection all exacerbated disorders such as anorexia, muscle dysmorphia and binge eating.

Binge eating disorder puts people at risk for obesity, metabolic syndrome, abnormal cardiac function and suicidal thoughts. Treatment goals include reducing the frequency of binge eating episodes by removing "trigger" foods, as well as addressing underlying anxiety or depression. Treatment with medication and talk therapy is effective about only half the time, Murray said.

For this study, Murray and his colleagues analyzed brain scans and other data from 71 children with diagnosed binge eating disorder and 74 children without binge eating disorder, who are part of a large longitudinal study called the Adolescent Brain and Cognitive Development Study. That study includes data of 11,875 children ages 9-10 who were enrolled in 2016-2018 and recruited from 21 sites around the U.S.

In the children with binge eating disorder, they saw elevations in gray matter density in areas that are typically "pruned" during healthy brain development. Synaptic pruning, a development phase that occurs between ages 2 and 10, eliminates synapses that are no longer used, making the brain more efficient. Disturbed synaptic pruning is linked to a number of psychiatric disorders.

"This study suggests to me that binge eating disorder is wired in the brain, even from a very, very early age," Murray said. "The question that we don't know, which is something that we will address in time, is whether successful treatment of binge eating disorder in kids helps correct brain development. The prognosis of almost all psychiatric diseases is better if you can treat them in childhood."

https://www.sciencedaily.com/releases/2022/03/220315162813.htm

100g of cranberries a day improves cardiovascular health

March 22, 2022

Science Daily/King's College London

A new clinical trial found daily consumption of cranberries for one month improved cardiovascular function in healthy men.

The new study, published today in Food & Function, included 45 healthy men who consumed whole cranberry powder equivalent to 100g of fresh cranberries per day (9 g powder) or a placebo for one month. Those consuming cranberry had a significant improvement in flow-mediated dilation (FMD), which signals improvement of heart and blood vessel function. FMD is considered a sensitive biomarker of cardiovascular disease risk and measures how blood vessels widen when blood flow increases.

Dr. Ana Rodriguez-Mateos, Senior Lecturer in Nutrition at the Department of Nutritional Sciences at King's College London and senior author of the study, said: "The increases in polyphenols and metabolites in the bloodstream and the related improvements in flow-mediated dilation after cranberry consumption emphasise the important role cranberries may play in cardiovascular disease prevention. The fact that these improvements in cardiovascular health were seen with an amount of cranberries that can be reasonably consumed daily makes cranberry an important fruit in the prevention of cardiovascular disease for the general public."

Low consumption of fruits and vegetables is one of the top modifiable risk factors associated with a higher incidence of cardiovascular disease worldwide. Growing evidence continues to link the polyphenols from berries with heart health benefits. Cranberries are rich in unique proanthocyanidins that have distinct properties compared to polyphenols found in other fruits.

This study explored whole cranberry freeze-dried powder, equivalent to 100g of fresh cranberries, and its impact on cardiovascular health. The results demonstrated that consumption of cranberries as part of a healthy diet can help reduce the risk of cardiovascular disease by improving blood vessel function.

An initial pilot study was completed with five healthy young men to confirm the biological activity of the whole cranberry freeze-dried powder. The pilot concluded that cranberry consumption increased FMD and confirmed dosing. The main study was a gold standard study design examining 45 healthy men each consuming two packets of whole cranberry freeze-dried powder equivalent to 100g of fresh cranberries, or a placebo, daily for one month. The study found significant improvements in FMD two hours after first consumption and after one month of daily consumption showing both immediate and chronic benefit. In addition, metabolites were also identified and predicted the positive effects seen in FMD. These results conclude that cranberries can play an important role in supporting cardiovascular health and good blood vessel function.

Dr. Christian Heiss, Professor of Cardiovascular Medicine at the University of Surrey and co-author of the study said: "Our findings provide solid evidence that cranberries can significantly affect vascular health even in people with low cardiovascular risk. This study further indicates that specific metabolites present in blood after cranberry consumption are related to the beneficial effects."

https://www.sciencedaily.com/releases/2022/03/220322111245.htm

How gut microbes work to tame intestinal inflammation

March 16, 2022

Science Daily/Harvard Medical School

Bile acids made by the liver have long been known for their critical role in helping to absorb the food we ingest.

But, according to a series of new studies from Harvard Medical School, these fat- and vitamin-dissolving substances are also important players in gut immunity and inflammation because they regulate the activity of key immune cells linked to a range of inflammatory bowel conditions, such as ulcerative colitis and Crohn's disease.

An initial report in 2020 mapped out the effects of bile acids on mouse gut immunity, but left some key questions unanswered: First, just how do bile acids get gut immune cells to perform their immune-regulatory work? Second, which bacteria and bacterial enzymes produce these bile acids? Third, do these bile acids play a role in human intestinal inflammation?

Now, two studies led by the same team of investigators -- one published March 16 in Nature and one published in Cell Host & Microbe in 2021 -- answer these questions and add further clarity to the initial observations. The research, conducted at the intersection of chemical biology, microbiology, and immunology, was co-led by Sloan Devlin, assistant professor of biological chemistry and molecular pharmacology, and Jun Huh, associate professor of immunology at HMS.

The studies identify three bile acid metabolites and corresponding bacterial genes that produce molecules that affect the activity of inflammation-regulating immune cells. The work also demonstrates that the presence and activity of these bacteria and the immune molecules they produce are notably reduced in patients with inflammatory bowel disease (IBD).

"We carry trillions of bacteria in and on our bodies, and a growing body of research indicates that gut bacteria can affect host immune responses," Huh said. "Our findings provide a novel mechanistic insight into how these bacteria work to mediate immune regulation in the gut."

The findings, based on experiments in mice and human stool samples, reveal the identity of three critical microbial players in this cascade and the bacterial genes that regulate bile acid modification. Furthermore, they show that intestinal samples from patients with conditions such as ulcerative colitis or Crohn's disease have markedly lower levels of both the anti-inflammatory molecules and the bacterial genes responsible for their production.

The findings bring scientists a step closer to developing small-molecule treatments and live bacterial therapeutics that regulate intestinal inflammation.

"All three molecules and the bacterial genes that we discovered that produce these molecules are reduced in patients with IBD," Devlin said. "Restoring the presence of either the compounds or the bacteria that make them offers a possible therapeutic avenue to treat a range of inflammatory diseases marked by these deficiencies and affecting millions of people worldwide."

https://www.sciencedaily.com/releases/2022/03/220316120813.htm

Weighing up: What’s the bottom line when it comes to weight loss?

March 3, 2022

Science Daily/University of South Australia

When it comes to weight loss, many of us have dabbled in the latest diets. But whether you're cutting carbs or keeping to keto, new research from the University of South Australia shows that diet trends can cost more than your waistline and leave a hefty hole in your hip pocket.

In a new study, UniSA researchers have evaluated the affordability of popular diets, comparing them to the recommendations within the Australian Guide to Health Eating (AGHE), and the Mediterranean Diet, finding that costs of cutting your calories can vary by up to $300 per week.

The research shows that the most cost-effective diet was modelled from the AGHE and adapted for weight loss through calorie restriction. This meal plan included all five core food groups and a range of affordable staple items such as breads, pasta, and legumes, as well as lower amounts of animal products.

The diet plans that were most expensive typically restricted multiple food groups and included premium products such as organic produce, protein supplements, low-carbohydrate replacements, and high protein bread.

In Australia, more than 2.5 million Australians had tried a weight loss diet.

Lead researcher Associate Professor Karen Murphy says understanding the costs of weight loss programs is important, especially when people are facing financial struggles and reduced access to fresh produce amid COVID-19 and current floods.

"In Australia, around 12.5 million adults are overweight or obese. That's two in every three adults, or 67 per cent of our adult population," Assoc Prof Karen Murphy says.

"Not surprisingly, interest in weight loss diets continues to rise, yet very rarely are the associated costs of these programs reported.

"In our research, we assessed the weekly costs of seven different meal plans and found that weekly grocery shopping of entire product units cost between $345-$625, which is substantially higher than more than what the average Australian spends on groceries each week.

"Understanding the costs behind the range of diets on offer is important as the financial feasibility of sticking to these programs may be questionable for certain people, including low-income earners.

"Additionally, there tends to be a misconception that consuming a healthy diet made up of the five key food groups, like the AGHE, is too expensive, which it's really not."

The study showed that some of the more expensive diets absorbed up to 13 per cent of disposable income*.

In addition to costs, UniSA PhD candidate, Ella Bracci, says nutrition is also key to starting a new diet.

"It doesn't matter whether you chose keto or carb-free, weight loss is always linked to calorie intake -- if you reduce the number of calories you consume, you will lose weight," Bracci says.

"Some diets purposely restrict certain food groups -- such breads and pasta -- to help change unhealthy habits. But it's also important to realise that the restrictive patterns of some diets can create unhealthy relationships with food and put you at risk of nutritional deficiency if followed without guidance from a qualified nutritionist or dietitian.

"Healthy eating principles such as those within the Australian Guide to Healthy Eating (AGHE) and the Mediterranean Diet place an emphasis on fresh produce and staple foods. While an incorrect perception exists that these can cost more, eating a healthy diet doesn't need to break the bank.

"Shop for specials and mark-downs, buy in season or frozen, dried and canned produce, choose home-brand or non-premium products where possible, and buy in bulk where appropriate.

"Weigh up your options wisely and you can reduce your waistline without cutting into your bottom line."

https://www.sciencedaily.com/releases/2022/03/220303112233.htm

Children eat what they like, but food intake driven more by what they dislike

February 22, 2022

Science Daily/Penn State

It is often said that "children eat what they like," but the results of a new study by Penn State nutritionists and sensory scientists suggests that when it comes to meals, it is more accurate and more relevant to say, "children do not eat what they dislike."

There is an important difference, according to lead researcher Kathleen Keller, associate professor in the departments of Nutritional Sciences and Food Science, who conducted an experiment involving 61 children ages 4-6 years to assess the relationship between their liking of foods in a meal and subsequent intake. The research revealed that when presented with a meal, disliking is a stronger predictor of what youngsters eat than liking.

"In other words, rather than high-liking driving greater intake, our study data indicate that lower-liking led children to avoid some foods and leave them on the plate," she said. "Kids have a limited amount of room in their bellies, so when they are handed a tray, they gravitate toward their favorite thing and typically eat that first, and then make choices about whether to eat other foods."

Study co-author John Hayes, professor of food science and director of the Sensory Evaluation Center in the College of Agricultural Sciences, puts it another way.

"For 50 plus years, we've known liking and intake are positively correlated, but this often leads to the mistaken assumption that if it tastes better, you will eat more," he said. "Reality is a bit more nuanced. In adults, we know that if you really like a food, you may or may not eat it. But if you don't like it, you'll rarely or never eat it. These new data show the same pattern is true in young kids."

Children participated in two identical laboratory sessions in the study conducted in Keller's Children's Eating Behavior Laboratory in the College of Health and Human Development, where seven foods -- chicken nuggets, ketchup, potato chips, grapes, broccoli, cherry tomatoes and cookies -- were included on a tray. Also included were two beverages, fruit punch and milk.

Before eating the meals, children were asked to rate their liking of each food on the following five-point scale -- Super Bad, Bad, Maybe Good-Maybe Bad, Good and Super Good. After the children had eaten as much of the meal as they wanted, the researchers weighed what they ate and compared the results with what the kids said they liked and disliked. The correlations were striking.

In findings recently published in the journal Appetite, the researchers reported that the relationship between liking and intake was not strong for most of the foods. For instance, only liking for potato chips, grapes, cherry tomatoes and fruit punch was positively associated with the amount consumed. But no associations were found between liking and intake of other meal items.

However, there was a strong correlation between consumption -- or nonconsumption in this case -- and the foods the children said they didn't like. At a multi-component meal, rather than eating what they like, these data are more consistent with the notion that children do not eat what they dislike, the researchers concluded.

Even at a young age, children's food choices are influenced by their parents and peers, Keller pointed out. So, we need to be careful with assumptions about what truly is driving their behavior when they sit down to eat a meal.

"They pick up on what is said around the table about what foods are good, and while that may not actually correspond to kids eating them, they are taking it all in, and that's affecting their perceptions of foods," she said. "Milk is a good example of that -- for some families, there may be a health halo effect around milk. Kids learn from an early age that drinking milk will give them a strong body, so they may drink milk even if it's not their favorite beverage."

Because children in the United States continue to consume insufficient amounts of vegetables, the findings of research projects such as this one are of great interest to parents, many of whom struggle to get their kids to eat vegetables, Keller believes. Parents want to know how they can improve their kids' nutrition.

"Some parents struggle with kids who are very picky eaters," she said. "That can cause long-term nutrition issues and creates a lot of stress for the family. I think picky eating is one of the most common complaints that I hear from parents -- 'How do I get my child to accept more foods? How do I make the dinner experience better and easier for my family?'"

https://www.sciencedaily.com/releases/2022/02/220222161826.htm