Eating more fruit and vegetables linked to less stress – study

Eating a diet rich in fruit and vegetables is associated with less stress, according to new research from Edith Cowan University (ECU).

The study examined the link between fruit and vegetable intake and stress levels of more than 8,600 Australians aged between 25 and 91 participating in the Australian Diabetes, Obesity and Lifestyle (AusDiab) Study from Baker Heart and Diabetes Institute.

The findings revealed people who ate at least 470 grams of fruit and vegetables daily had 10 per cent lower stress levels than those who consumed less than 230 grams. The World Health Organization (WHO) recommends eating at least 400 grams of fruit and vegetables per day.

Lead researcher, PhD candidate Simone Radavelli-Bagatini from ECU’s Institute for Nutrition Research, said the study strengthens the link between diets rich in fruit and vegetables and mental wellbeing.

“We found that people who have higher fruit and veggie intakes are less stressed than those with lower intakes, which suggests diet plays a key role in mental wellbeing,” said Ms Radavelli-Bagatini.

A growing issue

Mental health conditions are an increasing problem in Australia and around the world. Around one in two Australians will experience a mental health issue in their lifetime. Globally, approximately 1 in 10 people live with a mental health disorder.

According to Ms Radavelli-Bagatini, some stress is considered normal, but long-term exposure can significantly impact mental health.

“Long-term and unmanaged stress can lead to a range of health problems including heart disease, diabetes, depression and anxiety so we need to find ways to prevent and possibly alleviate mental health problems in the future,” said Ms Radavelli-Bagatini.

The benefits of a healthy diet are well known, but only 1 in 2 Australians eat the recommended two serves of fruit per day and fewer than 1 in 10 eat the recommended five serves of vegetables each day.

“Previous studies have shown the link between fruit and vegetable consumption and stress in younger adults, but this is the first time we’re seeing similar results across adults of all ages,” said Ms Radavelli-Bagatini.

“The study’s findings emphasise that it’s important for people to have a diet rich in fruit and vegetables to potentially minimise stress.”

Food and mood

While the mechanisms behind how fruit and vegetable consumption influences stress are still unclear, Ms Radavelli-Bagatini said key nutrients could be a factor.

“Vegetables and fruits contain important nutrients such as vitamins, minerals, flavonoids and carotenoids that can reduce inflammation and oxidative stress, and therefore improve mental wellbeing,” she said.

“Inflammation and oxidative stress in the body are recognised factors that can lead to increased stress, anxiety and lower mood.”

“These findings encourage more research into diet and specifically what fruits and vegetables provide the most benefits for mental health.”

The research is part of ECU’s recently launched Institute for Nutrition Research, which aims to investigate how nutrition can help prevent and treat chronic health conditions.

‘Fruit and vegetable intake is inversely associated with perceived stress across the adult lifespan’ was published in Clinical Nutrition.

Eating sardines regularly helps prevent type 2 diabetes

Omega 3 - come and get it
Omega 3 – come and get it


The health benefits of sardines and oily fish are widely known: their high levels of unsaturated fats help to regulate cholesterol levels and prevent the onset of cardiovascular diseases. However, the benefits don’t end there. A study led by Diana Diaz Rizzolo, lecturer and researcher of the Universitat Oberta de Catalunya’s (UOC) Faculty of Health Sciences and the August Pi i Sunyer Biomedical Research Institute (IDIBAPS), has discovered that the regular consumption of sardines helps to prevent the onset of type 2 diabetes. Nutrients found in high quantities in sardines – such as taurine, omega 3, calcium and vitamin D – help to protect against this disease which, according to CIBERDEM’s Di@betes study, affects around 14% of the Spanish population over the age of 18.

“Not only are sardines reasonably priced and easy to find, but they are safe and help to prevent the onset of type 2 diabetes. This is a huge scientific discovery. It is easy to recommend this food during medical check-ups, and it is widely accepted by the population”, explained Diana D. Rizzolo.

Researchers from the Diabetes and Obesity Research Laboratory and the Primary Care Research Group, both from IDIBAPS; the IMIM, the Fatty Acid Research Institute (EUA), the Universitat de Barcelona, CIBERDEM and the Department of Endocrinology and Nutrition of the Hospital Clínic de Barcelona also participated in the research project. The results of the study were published openly in the prestigious Clinical Nutrition journal.

Two cans of sardines a week

The study enrolled 152 patients aged 65 years and older who had been diagnosed with prediabetes (blood glucose levels between 100-124 mg/dl) from three different Primary Care centres. All of these patients were put on a nutritional programme that sought to reduce the risk of them developing the disease, but only the intervention group added 200 grams of sardines to their diet every week (two cans of sardines in olive oil). To facilitate this consumption, and with thanks to the Alicia Foundation, these study participants received a list of recipes including canned sardines. Participants were advised to eat the sardine whole, without removing the bones, as these are particularly rich in calcium and vitamin D.

Of the group that did not include sardines in their diet, 27% of the members were at a high risk of suffering from diabetes (measured via the FINDRISC questionnaire). After one year, 22% found themselves in the same category. Of the group that included sardines in their diet, 37% of the members were at a high risk of suffering from diabetes at the start of the study. After one year, only 8% remained at a very high risk. Improvements were also seen in other important biochemical parameters, such as a reduced insulin resistance index (HOMA-IR), increased “good” cholesterol (HDL), increased hormones that accelerate the breakdown of glucose (adiponectin) and decreased triglycerides and blood pressure, amongst others.

The study was carried out on participants aged 65 and above because the incidence of diabetes is much higher in elderly people than in the young population: “As we get older, restrictive diets (in terms of calories or food groups) can help to prevent the onset of diabetes. However, the cost-benefit ratio is not always positive, as we found in other studies”, stated doctor Rizzolo. “However, the results lead us to believe that we could obtain an equally significant preventive effect in the younger population.”

The protective role of food, but not of supplements

The fact that foods such as sardines – which are rich in taurine, omega 3, calcium and vitamin D – have a clear protective effect against the onset of diabetes does not mean that taking these supplements in isolation will have the same effect. “Nutrients can play an essential role in the prevention and treatment of many different pathologies, but their effect is usually caused by the synergy that exists between them and the food that they are contained in. Sardines will therefore have a protective element because they are rich in the aforementioned nutrients, whereas nutrients taken in isolation in the form of supplements won’t work to the same extent”, claimed Rizzolo.

Researchers have begun studying the effect of sardines on the intestinal microbiota in a second phase of the study, “since it affects the regulation of many biological process, and we need to understand if they have played a part in this protective effect against diabetes 2”, she added. They have also initiated studies on the modulation of the expression of certain genes related to inflammation, which could play a role in the onset of diabetes 2 and various other diseases.

Many consumers misinterpret food date labels, yet use them with confidence

Consumer education is needed to increase understanding of food date labels according to a new study in the Journal of Nutrition Education and Behavior

Example of an illustrated message. CREDIT Journal of Nutrition Education and Behavior

Misunderstanding food date labeling is common and educational communications are needed to improve consumer understanding, according to a new study in the Journal of Nutrition Education and Behavior, published by Elsevier.

Does it mean “spoiled – throw it out,” or “might not taste as good as it could anymore?” Food date labels (e.g., “USE By August 16”) can play an important role in helping consumers make informed decisions about food, and ultimately prevent unsafe consumption and waste of food. Researchers surveyed 2,607 adults in the United States to assess consumer understanding of the streamlined 2-date labeling system and explore the relative effectiveness of educational messages in increasing understanding.

“Our study showed that an overwhelming majority of consumers say that they use food date labels to make decisions about food and say they know what the labels mean,” said Catherine Turvey, MPH, Department of Exercise and Nutrition Sciences, Milken Institute School of Public Health, The George Washington University, Washington, DC, USA. “Despite confidently using date labels, many consumers misinterpreted the labels and continued to misunderstand even after reading educational messaging that explained the labels’ meaning.”

Less than half (46 percent) of study respondents knew that the “BEST If Used By” label specifically indicates that food quality may deteriorate after the date on the label. Less than one-quarter (24 percent) of study respondents knew that the “USE By” label means that food is not safe to eat after the date on the label.

Researchers explored if framing the messages with values like saving money or avoiding waste, would impact the effectiveness of messages at increasing consumer understanding. None of the seven value frames tested was significantly more effective at increasing understanding than another, but all messages significantly increased consumer’s general understanding of the labels.

After viewing educational messages, 37 percent of consumers still did not understand the specific meaning of the “BEST If Used By” label and 48 percent did not understand the specific meaning of the “USE By” label.

“Responses to the survey suggest that date labels are so familiar that some consumers believe they are boring, self-explanatory, or common sense despite misunderstanding the labels,” said Ms. Turvey. “Unwarranted confidence and the familiarity of date labels may make consumers less attentive to educational messaging that explains the food industry’s labeling system.”

Future communication campaigns will have to capture the attention of people who think they already know what date labels mean, find the information tedious, or are satisfied with a rough understanding of labels. Educating consumers about the meaning of the labels has growing implications for food waste and food safety as the 2-date labeling system becomes more widely adopted and gains support from non-profits and government institutions.


One cup of leafy green vegetables a day lowers risk of heart disease

New Edith Cowan University (ECU) research has found that by eating just one cup of nitrate-rich vegetables each day people can significantly reduce their risk of heart disease.

Kale in shape of a human heart

New Edith Cowan University (ECU) research has found that by eating just one cup of nitrate-rich vegetables each day people can significantly reduce their risk of heart disease.

The study investigated whether people who regularly ate higher quantities of nitrate-rich vegetables, such as leafy greens and beetroot, had lower blood pressure, and it also examined whether these same people were less likely to be diagnosed with heart disease many years later.

Cardiovascular diseases are the number one cause of death globally, taking around 17.9 million lives each year.

Researchers examined data from over 50,000 people residing in Denmark taking part in the Danish Diet, Cancer, and Health Study over a 23-year period. They found that people who consumed the most nitrate-rich vegetables had about a 2.5 mmHg lower systolic blood pressure and between 12 to 26 percent lower risk of heart disease.

Lead researcher Dr Catherine Bondonno from ECU’s Institute for Nutrition Research said identifying diets to prevent heart disease was a priority.

“Our results have shown that by simply eating one cup of raw (or half a cup of cooked) nitrate-rich vegetables each day, people may be able to significantly reduce their risk of cardiovascular disease,” Dr Bondonno said.

“The greatest reduction in risk was for peripheral artery disease (26 percent), a type of heart disease characterised by the narrowing of blood vessels of the legs, however we also found people had a lower risk of heart attacks, strokes and heart failure.”

Forget the supplements

The study found that the optimum amount of nitrate-rich vegetables was one cup a day and eating more than that didn’t seem to give any additional benefits.

“People don’t need to be taking supplements to boost their nitrate levels because the study showed that one cup of leafy green vegetables each day is enough to reap the benefits for heart disease,” Dr Bondonno said.

“We did not see further benefits in people who ate higher levels of nitrate rich vegetables.”

Smoothies are ok

Dr Bondonno said hacks such as including a cup of spinach in a banana or berry smoothie might be an easy way to top up our daily leafy greens.

“Blending leafy greens is fine, but don’t juice them. Juicing vegetables removes the pulp and fibre,” Dr Bondonno said.

The paper “Vegetable nitrate intake, blood pressure and incident cardiovascular disease: Danish Diet, Cancer, and Health Study” is published in the European Journal of Epidemiology. It is a collaboration between Edith Cowan University, the Danish Cancer Society and The University of Western Australia.

The research adds to growing evidence linking vegetables generally and leafy greens specifically with improved cardiovascular health and muscle strength. This evidence includes two recent ECU studies exploring cruciferous vegetables and blood vessel health and green leafy vegetables and muscle strength.

Childhood diet and exercise creates healthier, less anxious adults

Study lead author and UCR physiology doctoral student Marcell Cadney. CREDIT Marcell Cadney/UCR

Exercise and a healthy diet in childhood leads to adults with bigger brains and lower levels of anxiety, according to new UC Riverside research in mice.

Though diet and exercise are consistently recommended as ways to promote health, this study is the first to examine the long-lasting, combined effects of both factors when they are experienced early in life.

“Any time you go to the doctor with concerns about your weight, almost without fail, they recommend you exercise and eat less,” said study lead and UCR physiology doctoral student Marcell Cadney. “That’s why it’s surprising most studies only look at diet or exercise separately. In this study, we wanted to include both.”

The researchers determined that early-life exercise generally reduced anxious behaviors in adults. It also led to an increase in adult muscle and brain mass. When fed “Western” style diets high in fat and sugar, the mice not only became fatter, but also grew into adults that preferred unhealthy foods.

These findings have recently been published in the journal Physiology and Behavior. To obtain them, the researchers divided the young mice into four groups — those with access to exercise, those without access, those fed a standard, healthy diet and those who ate a Western diet.

Mice started on their diets immediately after weaning, and continued on them for three weeks, until they reached sexual maturity. After an additional eight weeks of “washout,” during which all mice were housed without wheels and on the healthy diet, the researchers did behavioral analysis, measured aerobic capacity, and levels of several different hormones.

One of those they measured, leptin, is produced by fat cells. It helps control body weight by increasing energy expenditure and signaling that less food is required. Early-life exercise increased adult leptin levels as well as fat mass in adult mice, regardless of the diet they ate.

Previously, the research team found that eating too much fat and sugar as a child can alter the microbiome for life, even if they later eat healthier. Going forward, the team plans to investigate whether fat or sugar is more responsible for the negative effects they measured in Western-diet-fed mice.

Together, both studies offer critical opportunities for health interventions in childhood habits.

“Our findings may be relevant for understanding the potential effects of activity reductions and dietary changes associated with obesity,” said UCR evolutionary physiologist Theodore Garland.

In other words, getting a jump start on health in the early years of life is extremely important, and interventions may be even more critical in the wake of the pandemic.

“During the COVID-19 lockdowns, particularly in the early months, kids got very little exercise. For many without access to a park or a backyard, school was their only source of physical activity,” Cadney said. “It is important we find solutions for these kids, possibly including extra attention as they grow into adults.”

Given that exercise was also shown to reduce adult anxiety, Cadney believes children who face these challenges may face unique physical and mental health issues as they become adults in the coming decade.