In January, many people are setting new year’s resolutions around healthy eating. Achieving these is often challenging – it can be difficult to change our eating habits. But healthy diets can enhance physical and mental health, so improving what we eat is a worthwhile goal.

One reason it’s difficult to change our eating habits relates to our “food environments”. This term describes:

The collective physical, economic, policy and sociocultural surroundings, opportunities and conditions that influence people’s food and beverage choices and nutritional status.

Our current food environments are designed in ways that often make it easier to choose unhealthy foods than healthy ones. But it’s possible to change certain aspects of our personal food environments, making eating healthier a little easier.

Unhealthy food environments

It’s not difficult to find fast-food restaurants in Australian cities. Meanwhile, there are junk foods at supermarket checkouts, service stations and sporting venues. Takeaway and packaged foods and drinks routinely come in large portion sizes and are often considered tastier than healthy options.

Our food environments also provide us with various prompts to eat unhealthy foods via the media and advertising, alongside health and nutrition claims and appealing marketing images on food packaging.

At the supermarket, unhealthy foods are often promoted through prominent displays and price discounts.

We’re also exposed to various situations in our everyday lives that can make healthy eating challenging. For example, social occasions or work functions might see large amounts of unhealthy food on offer.

Not everyone is affected in the same way

People differ in the degree to which their food consumption is influenced by their food environments.

This can be due to biological factors (for example, genetics and hormones), psychological characteristics (such as decision making processes or personality traits) and prior experiences with food (for example, learned associations between foods and particular situations or emotions).

People who are more susceptible will likely eat more and eat more unhealthy foods than those who are more immune to the effects of food environments and situations.

Those who are more susceptible may pay greater attention to food cues such as advertisements and cooking smells, and feel a stronger desire to eat when exposed to these cues. Meanwhile, they may pay less attention to internal cues signalling hunger and fullness. These differences are due to a combination of biological and psychological characteristics.

These people might also be more likely to experience physiological reactions to food cues including changes in heart rate and increased salivation.

Other situational cues can also prompt eating for some people, depending on what they’ve learned about eating. Some of us tend to eat when we’re tired or in a bad mood, having learned over time eating provides comfort in these situations.

Other people will tend to eat in situations such as in the car during the commute home from work (possibly passing multiple fast-food outlets along the way), or at certain times of day such as after dinner, or when others around them are eating, having learned associations between these situations and eating.

Being in front of a TV or other screen can also prompt people to eat, eat unhealthy foods, or eat more than intended.

Making changes

While it’s not possible to change wider food environments or individual characteristics that affect susceptibility to food cues, you can try to tune into how and when you’re affected by food cues. Then you can restructure some aspects of your personal food environments, which can help if you’re working towards healthier eating goals.

Although both meals and snacks are important for overall diet quality, snacks are often unplanned, which means food environments and situations may have a greater impact on what we snack on.

Foods consumed as snacks are often sugary drinks, confectionery, chips and cakes. However, snacks can also be healthy (for example, fruits, nuts and seeds).

Try removing unhealthy foods, particularly packaged snacks, from the house, or not buying them in the first place. This means temptations are removed, which can be especially helpful for those who may be more susceptible to their food environment.

Planning social events around non-food activities can help reduce social influences on eating. For example, why not catch up with friends for a walk instead of lunch at a fast-food restaurant.

Creating certain rules and habits can reduce cues for eating. For example, not eating at your desk, in the car, or in front of the TV will, over time, lessen the effects of these situations as cues for eating.

You could also try keeping a food diary to identify what moods and emotions trigger eating. Once you’ve identified these triggers, develop a plan to help break these habits. Strategies may include doing another activity you enjoy such as going for a short walk or listening to music – anything that can help manage the mood or emotion where you would have typically reached for the fridge.

Write (and stick to) a grocery list and avoid shopping for food when hungry. Plan and prepare meals and snacks ahead of time so eating decisions are made in advance of situations where you might feel especially hungry or tired or be influenced by your food environment.

Georgie Russell, Senior Lecturer, Institute for Physical Activity and Nutrition (IPAN), Deakin University and Rebecca Leech, NHMRC Emerging Leadership Fellow, School of Exercise and Nutrition Sciences, Deakin University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

The United States Department of Agriculture last week reported that a pig on a backyard farm in Oregon was infected with bird flu.

As the bird flu situation has evolved, we’ve heard about the A/H5N1 strain of the virus infecting a range of animals, including a variety of birds, wild animals and dairy cattle.

Fortunately, we haven’t seen any sustained spread between humans at this stage. But the detection of the virus in a pig marks a worrying development in the trajectory of this virus.

How did we get here?

The most concerning type of bird flu currently circulating is clade 2.3.4.4b of A/H5N1, a strain of influenza A.

Since 2020, A/H5N1 2.3.4.4b has spread to a vast range of birds, wild animals and farm animals that have never been infected with bird flu before.

While Europe is a hotspot for A/H5N1, attention is currently focused on the US. Dairy cattle were infected for the first time in 2024, with more than 400 herds affected across at least 14 US states.

Bird flu has enormous impacts on farming and commercial food production, because infected poultry flocks have to be culled, and infected cows can result in contaminated diary products. That said, pasteurisation should make milk safe to drink.

While farmers have suffered major losses due to H5N1 bird flu, it also has the potential to mutate to cause a human pandemic.

Birds and humans have different types of receptors in their respiratory tract that flu viruses attach to, like a lock (receptors) and key (virus). The attachment of the virus allows it to invade a cell and the body and cause illness. Avian flu viruses are adapted to birds, and spread easily among birds, but not in humans.

So far, human cases have mainly occurred in people who have been in close contact with infected farm animals or birds. In the US, most have been farm workers.

The concern is that the virus will mutate and adapt to humans. One of the key steps for this to happen would be a shift in the virus’ affinity from the bird receptors to those found in the human respiratory tract. In other words, if the virus’ “key” mutated to better fit with the human “lock”.

A recent study of a sample of A/H5N1 2.3.4.4b from an infected human had worrying findings, identifying mutations in the virus with the potential to increase transmission between human hosts.

Why are pigs a problem?

A human pandemic strain of influenza can arise in several ways. One involves close contact between humans and animals infected with their own specific flu viruses, creating opportunities for genetic mixing between avian and human viruses.

Pigs are the ideal genetic mixing vessel to generate a human pandemic influenza strain, because they have receptors in their respiratory tracts which both avian and human flu viruses can bind to.

This means pigs can be infected with a bird flu virus and a human flu virus at the same time. These viruses can exchange genetic material to mutate and become easily transmissible in humans.

Interestingly, in the past pigs were less susceptible to A/H5N1 viruses. However, the virus has recently mutated to infect pigs more readily.

In the recent case in Oregon, A/H5N1 was detected in a pig on a non-commercial farm after an outbreak occurred among the poultry housed on the same farm. This strain of A/H5N1 was from wild birds, not the one that is widespread in US dairy cows.

The infection of a pig is a warning. If the virus enters commercial piggeries, it would create a far greater level of risk of a pandemic, especially as the US goes into winter, when human seasonal flu starts to rise.

How can we mitigate the risk?

Surveillance is key to early detection of a possible pandemic. This includes comprehensive testing and reporting of infections in birds and animals, alongside financial compensation and support measures for farmers to encourage timely reporting.

Strengthening global influenza surveillance is crucial, as unusual spikes in pneumonia and severe respiratory illnesses could signal a human pandemic. Our EPIWATCH system looks for early warnings of such activity, which can speed up vaccine development.

If a cluster of human cases occurs, and influenza A is detected, further testing (called subtyping) is essential to ascertain whether it’s a seasonal strain, an avian strain from a spillover event, or a novel pandemic strain.

Early identification can prevent a pandemic. Any delay in identifying an emerging pandemic strain enables the virus to spread widely across international borders.

Australia’s first human case of A/H5N1 occurred in a child who acquired the infection while travelling in India, and was hospitalised with illness in March 2024. At the time, testing revealed Influenza A (which could be seasonal flu or avian flu), but subtyping to identify A/H5N1 was delayed.

This kind of delay can be costly if a human-transmissible A/H5N1 arises and is assumed to be seasonal flu because the test is positive for influenza A. Only about 5% of tests positive for influenza A are subtyped further in Australia and most countries.

In light of the current situation, there should be a low threshold for subtyping influenza A strains in humans. Rapid tests which can distinguish between seasonal and H5 influenza A are emerging, and should form part of governments’ pandemic preparedness.

A higher risk than ever before

The US Centers for Disease Control and Prevention states that the current risk posed by H5N1 to the general public remains low.

But with H5N1 now able to infect pigs, and showing worrying mutations for human adaptation, the level of risk has increased. Given the virus is so widespread in animals and birds, the statistical probability of a pandemic arising is higher than ever before.

The good news is, we are better prepared for an influenza pandemic than other pandemics, because vaccines can be made in the same way as seasonal flu vaccines. As soon as the genome of a pandemic influenza virus is known, the vaccines can be updated to match it.

Partially matched vaccines are already available, and some countries such as Finland are vaccinating high-risk farm workers.

C Raina MacIntyre, Professor of Global Biosecurity, NHMRC L3 Research Fellow, Head, Biosecurity Program, Kirby Institute, UNSW Sydney and Haley Stone, Research Associate, Biosecurity Program, Kirby Institute & CRUISE lab, Computer Science and Engineering, UNSW Sydney

This article is republished from The Conversation under a Creative Commons license. Read the original article.