Many of us try to eat more fruits and vegetables and less ultra-processed food. But why is sticking to your goals so hard?

High-fat, sugar-rich and salty foods are simply so enjoyable to eat. And it’s not just you – we’ve evolved that way. These foods activate the brain’s reward system because in the past they were rare.

Now, they’re all around us. In wealthy modern societies we are bombarded by advertising which intentionally reminds us about the sight, smell and taste of calorie-dense foods. And in response to these powerful cues, our brains respond just as they’re designed to, triggering an intense urge to eat them.

Here’s how food cravings work and what you can do if you find yourself hunting for sweet or salty foods.

What causes cravings?

A food craving is an intense desire or urge to eat something, often focused on a particular food.

We are programmed to learn how good a food tastes and smells and where we can find it again, especially if it’s high in fat, sugar or salt.

Something that reminds us of enjoying a certain food, such as an eye-catching ad or delicious smell, can cause us to crave it.

The cue triggers a physical response, increasing saliva production and gastric activity. These responses are relatively automatic and difficult to control.

What else influences our choices?

While the effect of cues on our physical response is relatively automatic, what we do next is influenced by complex factors.
Whether or not you eat the food might depend on things like cost, whether it’s easily available, and if eating it would align with your health goals.

But it’s usually hard to keep healthy eating in mind. This is because we tend to prioritise a more immediate reward, like the pleasure of eating, over one that’s delayed or abstract – including health goals that will make us feel good in the long term.

Stress can also make us eat more. When hungry, we choose larger portions, underestimate calories and find eating more rewarding.

Looking for something salty or sweet

So what if a cue prompts us to look for a certain food, but it’s not available?

Previous research suggested you would then look for anything that makes you feel good. So if you saw someone eating a doughnut but there were none around, you might eat chips or even drink alcohol.

But our new research has confirmed something you probably knew: it’s more specific than that.

If an ad for chips makes you look for food, it’s likely a slice of cake won’t cut it – you’ll be looking for something salty. Cues in our environment don’t just make us crave food generally, they prompt us to look for certain food “categories”, such as salty, sweet or creamy.

Food cues and mindless eating

Your eating history and genetics can also make it harder to suppress food cravings. But don’t beat yourself up – relying on willpower alone is hard for almost everyone.

Food cues are so powerful they can prompt us to seek out a certain food, even if we’re not overcome by a particularly strong urge to eat it. The effect is more intense if the food is easily available.

This helps explain why we can eat an entire large bag of chips that’s in front of us, even though our pleasure decreases as we eat. Sometimes we use finishing the packet as the signal to stop eating rather than hunger or desire.

Is there anything I can do to resist cravings?

We largely don’t have control over cues in our environment and the cravings they trigger. But there are some ways you can try and control the situations you make food choices in.

• Acknowledge your craving and think about a healthier way to satisfy it. For example, if you’re craving chips, could you have lightly-salted nuts instead? If you want something sweet, you could try fruit.
• Avoid shopping when you’re hungry, and make a list beforehand. Making the most of supermarket “click and collect” or delivery options can also help avoid ads and impulse buys in the aisle.
• At home, have fruit and vegetables easily available – and easy to see. Also have other nutrient dense, fibre-rich and unprocessed foods on hand such as nuts or plain yoghurt. If you can, remove high-fat, sugar-rich and salty foods from your environment.
• Make sure your goals for eating are SMART. This means they are specific, measurable, achievable, relevant and time-bound.
• Be kind to yourself. Don’t beat yourself up if you eat something that doesn’t meet your health goals. Just keep on trying.

Gabrielle Weidemann, Associate Professor in Psychological Science, Western Sydney University and Justin Mahlberg, Research Fellow, Pyschology, Monash University

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

The United States’ Centers for Disease Control and Prevention (CDC) has issued a health alert after the first case of H5N1 avian influenza, or bird flu, seemingly spread from a cow to a human.

A farm worker in Texas contracted the virus amid an outbreak in dairy cattle. This is the second human case in the US; a poultry worker tested positive in Colorado in 2022.

The virus strain identified in the Texan farm worker is not readily transmissible between humans and therefore not a pandemic threat. But it’s a significant development nonetheless.

Some background on bird flu

There are two types of avian influenza: highly pathogenic or low pathogenic, based on the level of disease the strain causes in birds. H5N1 is a highly pathogenic avian influenza.

H5N1 first emerged in 1997 in Hong Kong and then China in 2003, spreading through wild bird migration and poultry trading. It has caused periodic epidemics in poultry farms, with occasional human cases.

Influenza A viruses such as H5N1 are further divided into variants, called clades. The unique variant causing the current epidemic is H5N1 clade 2.3.4.4b, which emerged in late 2020 and is now widespread globally, especially in the Americas.

In the past, outbreaks could be controlled by culling of infected birds, and H5N1 would die down for a while. But this has become increasingly difficult due to escalating outbreaks since 2021.

Wild animals are now in the mix

Waterfowl (ducks, swans and geese) are the main global spreaders of avian flu, as they migrate across the world via specific routes that bypass Australia. The main hub for waterfowl to migrate around the world is Quinghai lake in China.

But there’s been an increasing number of infected non-waterfowl birds, such as true thrushes and raptors, which use different flyways. Worryingly, the infection has spread to Antarctica too, which means Australia is now at risk from different bird species which fly here.

H5N1 has escalated in an unprecedented fashion since 2021, and an increasing number of mammals including sea lions, goats, red foxes, coyotes, even domestic dogs and cats have become infected around the world.

Wild animals like red foxes which live in peri-urban areas are a possible new route of spread to farms, domestic pets and humans.

Dairy cows and goats have now become infected with H5N1 in at least 17 farms across seven US states.

What are the symptoms?

Globally, there have been 14 cases of H5N1 clade 2.3.4.4b virus in humans, and 889 H5N1 human cases overall since 2003.

Previous human cases have presented with a severe respiratory illness, but H5N1 2.3.4.4b is causing illness affecting other organs too, like the brain, eyes and liver.

For example, more recent cases have developed neurological complications including seizures, organ failure and stroke. It’s been estimated that around half of people infected with H5N1 will die.

The case in the Texan farm worker appears to be mild. This person presented with conjunctivitis, which is unusual.

Food safety

Contact with sick poultry is a key risk factor for human infection. Likewise, the farm worker in Texas was likely in close contact with the infected cattle.

The CDC advises pasteurised milk and well cooked eggs are safe. However, handling of infected meat or eggs in the process of cooking, or drinking unpasteurised milk, may pose a risk.

Although there’s no H5N1 in Australian poultry or cattle, hygienic food practices are always a good idea, as raw milk or poorly cooked meat, eggs or poultry can be contaminated with microbes such as salmonella and E Coli.

If it’s not a pandemic, why are we worried?

Scientists have feared avian influenza may cause a pandemic since about 2005. Avian flu viruses don’t easily spread in humans. But if an avian virus mutates to spread in humans, it can cause a pandemic.

One concern is if birds were to infect an animal like a pig, this acts as a genetic mixing vessel. In areas where humans and livestock exist in close proximity, for example farms, markets or even in homes with backyard poultry, the probability of bird and human flu strains mixing and mutating to cause a new pandemic strain is higher.

The cows infected in Texas were tested because farmers noticed they were producing less milk. If beef cattle are similarly affected, it may not be as easily identified, and the economic loss to farmers may be a disincentive to test or report infections.

How can we prevent a pandemic?

For now there is no spread of H5N1 between humans, so there’s no immediate risk of a pandemic.

However, we now have unprecedented and persistent infection with H5N1 clade 2.3.4.4b in farms, wild animals and a wider range of wild birds than ever before, creating more chances for H5N1 to mutate and cause a pandemic.

Unlike the previous epidemiology of avian flu, where hot spots were in Asia, the new hot spots (and likely sites of emergence of a pandemic) are in the Americas, Europe or in Africa.

Pandemics grow exponentially, so early warnings for animal and human outbreaks are crucial. We can monitor infections using surveillance tools such as our EPIWATCH platform.

The earlier epidemics can be detected, the better the chance of stamping them out and rapidly developing vaccines.

Although there is a vaccine for birds, it has been largely avoided until recently because it’s only partially effective and can mask outbreaks. But it’s no longer feasible to control an outbreak by culling infected birds, so some countries like France began vaccinating poultry in 2023.

For humans, seasonal flu vaccines may provide a small amount of cross-protection, but for the best protection, vaccines need to be matched exactly to the pandemic strain, and this takes time. The 2009 flu pandemic started in May in Australia, but the vaccines were available in September, after the pandemic peak.

To reduce the risk of a pandemic, we must identify how H5N1 is spreading to so many mammalian species, what new wild bird pathways pose a risk, and monitor for early signs of outbreaks and illness in animals, birds and humans. Economic compensation for farmers is also crucial to ensure we detect all outbreaks and avoid compromising the food supply.

C Raina MacIntyre, Professor of Global Biosecurity, NHMRC L3 Research Fellow, Head, Biosecurity Program, Kirby Institute, UNSW Sydney; Ashley Quigley, Senior Research Associate, Global Biosecurity, UNSW Sydney; Haley Stone, PhD Candidate, Biosecurity Program, Kirby Institute, UNSW Sydney; Matthew Scotch, Associate Dean of Research and Professor of Biomedical Informatics, College of Health Solutions, Arizona State University, and Rebecca Dawson, Research Associate, The Kirby Institute, UNSW Sydney

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