Anti-vaccination mothers have outsized voice on social media – pro-vaccination parents could make a difference


Vaccinations are important to protect against a host of diseases.
www.shutterstock.com

Brooke W. McKeever, University of South Carolina and Robert McKeever, University of South Carolina

A high school student from Ohio made national headlines recently by getting inoculated despite his family’s anti-vaccination beliefs.

Ethan Lindenberger, 18, who never had been vaccinated, had begun to question his parents’ decision not to immunize him. He went online to research and ask questions, posting to Reddit, a social discussion website, about how to be vaccinated. His online quest went viral.

In March 2019, he was invited to testify before a U.S. Senate Committee hearing on vaccines and preventable disease outbreaks. In his testimony, he said that his mother’s refusal to vaccinate him was informed partly by her online research and the misinformation about vaccines she found on the web.

Lindenberger’s mother is hardly alone. Public health experts have blamed online anti-vaccination discussions in part for New York’s worst measles outbreak in 30 years. Anti-vaccine activists also have been cited for the growth of anti-vaccination sentiments in the U.S. and abroad.

We are associate professors who study health communication. We are also parents who read online vaccination-related posts, and we decided to conduct research to better understand people’s communication behaviors related to childhood vaccinations. Our research examined the voices most central to this discussion online, mothers, and our findings show that those who oppose vaccinations communicate most about this issue.

What prompts mothers to speak out

A strong majority of parents in the U.S. support vaccinations, yet at the same time, anti-vaccination rates in the U.S. and globally are rising. The World Health Organization identified the reluctance or refusal to vaccinate despite the availability of vaccines as one of 10 top threats to global health in 2019.

Mothers are critical decision-makers in determining whether their children should be vaccinated. In our study, we surveyed 455 mothers online to determine who communicates most about vaccinations and why.

In general, previous research has shown that people evaluate opinion climates – what the majority opinion seems to say – before expressing their own ideas about issues. This is true particularly on controversial subjects such as affirmative action, abortion or immigration. If an individual perceives their opinion to be unpopular, they may be less likely to say what they think, especially if an issue receives a lot of media attention, a phenomenon known as the spiral of silence.

If individuals, however, have strong beliefs about an issue, they may express their opinions whether they are commonly held or minority perspectives. These views can dominate conversations as others online find support for their views and join in.

Our recent study found that mothers who contributed information online shared several perspectives. Mothers who didn’t strongly support childhood vaccinations were more likely to seek, pay attention to, forward information and speak out about the issue – compared to those who do support childhood vaccinations.

Those who believed that vaccinations were an important issue (whether they were for or against them) were more likely to express an opinion. And those who opposed vaccinations were more likely to post their beliefs online.

Ethan Lindenberger testifies before a congressional committee about his decision to be vaccinated against his family’s wishes.
AP Photo/Carolyn Kaster

How social media skews facts

Online news content can be influenced by social media information that millions of people read, and it can amplify minority opinions and health myths. For example, Twitter and Reddit posts related to the vaccine-autism myth can drive news coverage.

Those who expressed online opinions about vaccinations also drove news coverage. Other research we co-authored shows that posts related to the vaccine-autism myth were followed by online news stories related to tweets in the U.S., Canada and the U.K.

Recent reports about social media sites, such as Facebook, trying to interrupt false health information from spreading can help correct public misinformation. However, it is unclear what types of communication will counter misinformation and myths that are repeated and reinforced online.

Countering skepticism

Our work suggests that those who agree with the scientific facts about vaccination may not feel the need to pay attention to this issue or voice their opinions online. They likely already have made up their minds and vaccinated their children.

But from a health communication perspective, it is important that parents who support vaccination voice their opinions and experiences, particularly in online environments.

Studies show that how much parents trust or distrust doctors, scientists or the government influences where they land in the vaccination debate. Perspectives of other parents also provide a convincing narrative to understand the risks and benefits of vaccination.

Scientific facts and messaging about vaccines, such as information from organizations like the World Health Organization and the Centers for Disease Control and Prevention, are important in the immunization debate.

But research demonstrates that social consensus, informed in part by peers and other parents, is also an effective element in conversations that shape decisions.

If mothers or parents who oppose or question vaccinations continue to communicate, while those who support vaccinations remain silent, a false consensus may grow. This could result in more parents believing that a reluctance to vaccinate children is the norm – not the exception.

[ Expertise in your inbox. Sign up for The Conversation’s newsletter and get a digest of academic takes on today’s news, every day. ]The Conversation

Brooke W. McKeever, Associate Professor, University of South Carolina and Robert McKeever, Associate Professor, University of South Carolina

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

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As Scott Morrison heads to Washington, the US-Australia alliance is unlikely to change



Wes Mountain/The Conversation, CC BY-ND

David Smith, University of Sydney

Prime Minister Scott Morrison’s official visit to Washington this week carries some prestige. It is just the second “official visit” (including a state dinner) by a foreign leader during the Trump presidency, and the first by an Australian since John Howard in 2006. Despite a rocky start, relations between Australia and the US have been uniquely smooth in the Trump era.

Many traditional allies have learned to endure constant insults from the president. Trump complains bitterly about allies taking advantage of the United States in trade deals and defence alliances. France, Germany, South Korea, Japan, Denmark, Canada, Mexico and the whole of NATO have all been on the receiving end of Trump’s scorn.

In contrast, the leaders of a select group of Middle Eastern allies – Saudi Arabia, Israel, the UAE, and Egypt – have enjoyed extravagant backing from Trump, born of a mutual hostility to Iran and Barack Obama.

Australia seems to be in its own category as a long-standing ally that rarely attracts the attention of the president. In the absence of either tantrums or patronage, business as usual has quietly continued.

Australia’s unique position may be largely because we have a trade deficit with the United States, rather than the other way around. This is an issue of core importance to Trump, and the US gets its fifth-largest trade surplus from Australia at US$7.8 billion.

Australia’s outgoing ambassador, Joe Hockey, has cultivated a genuinely warm personal relationship with Trump that lubricates various bargains. It’s impossible to imagine him suffering the same fate as the UK’s Kim Darroch.

Morrison also understands the usefulness of a close personal relationship with the president and has steadily worked on this. It helps that Trump believes he has some political affinity with him.

But the relationship between the Australian and American governments is much broader than the one between president and prime minister. It is conducted behind the scenes every day by public servants on both sides and reflects decades of cooperation. Earlier this year, pro-Australian forces in the US government successfully defused Trump’s irritation at the volume of Australian aluminium exports to the US. Australia remains the only country with a complete exemption from American steel and aluminium tariffs.

This very stability may limit the scope of what Trump and Morrison can talk about. Most issues are relatively settled. However, the US-China trade war, and Australia’s role in it, will almost certainly be a topic of conversation.

Given the risks to Australia from a trade war, some had hoped Morrison could influence Trump to de-escalate tensions. In June, Morrison warned against the development of a “zero-sum mindset” on trade. He told a London audience that the World Trade Organisation, then under attack from the US, needed support as the US-China trade conflict put prosperity and living standards at risk.




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Back then, there was still hope of an agreement, which now seems more remote than ever. Morrison seems resigned to an enduring conflict between two of our largest trading partners. He has said the world will have to get used to it and that the conflict is all about the need to enforce the rules of global trade on China.

Australia has long shared American concerns that China flouts the rules to the extent that it undermines the whole system. Indeed, Australians have sometimes worried that Trump’s obsession with trade deficits is actually a distraction from this deeper issue.

In February, Hockey warned Trump against making a deal with China that would reduce the deficit while leaving structural issues unaddressed. But none of this means Morrison would accept an invitation from Trump to join the US in the trade war.

Morrison has already committed Australian support to the US effort to guard oil shipments from Iranian seizures in the Strait of Hormuz. This is the kind of invitation Australia rarely refuses. A frigate, surveillance and patrol aircraft and some personnel will go to the Persian Gulf, though it is unclear when.




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Infographic: what is the conflict between the US and Iran about and how is Australia now involved?


Other US allies, some of whom are signatories to the Iran nuclear deal, have declined to make even modest contributions such as these. They see the current crisis, correctly, as Trump’s fault and they fear provoking further conflict with Iran.

Even after Trump unilaterally withdrew the US from the Iran nuclear deal, reimposing sanctions that led to increased hostilities, the Morrison government opted to continue support for the deal, subject to Iranian compliance (which is now evaporating).

Both major parties are framing Australia’s support for the US in terms of our commitment to freedom of navigation and a rules-based international order.

Morrison is likely to reaffirm this commitment in Washington, without getting into discussions about why Trump withdrew from an agreement that his own intelligence agencies said was working. The recent demise of John Bolton as national security adviser will hopefully make it less likely that Australia faces any questions about deeper military involvement in the Gulf.

Morrison is keen to secure Trump’s first visit to Australia, for the President’s Cup golf tournament in December. While he lauds Trump as “a good president for Australia”, Australians are sceptical. A US Studies Centre poll in July found only 19% of Australians want to see Trump re-elected (that includes just 29% of Coalition voters).

In fairness to Trump, polls conducted in 2008 and 2012 found even smaller numbers of Australians wanted John McCain (16%) or Mitt Romney (5%) to win those presidential elections. The Republican Party this century has been well to the right of nearly every other mainstream conservative party in the world, including the Liberal Party.

Trump isn’t the first deeply unpopular president Australia has seen and he won’t be the last. In the 2019 Lowy Institute Poll, 64% of respondents say Australia “should remain close to the United States under President Donald Trump”.

There is no danger of that changing under Morrison.The Conversation

David Smith, Senior Lecturer in American Politics and Foreign Policy, Academic Director of the US Studies Centre, University of Sydney

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

Nuclear power should be allowed in Australia – but only with a carbon price



The Opal nuclear research reactor at Lucas Heights in Sydney. It does not produce nuclear energy but is used to produce medical radioisotopes and for other purposes.
Tracey Nearmy/AAP

John Quiggin, The University of Queensland

Looking at the state of policy on energy and climate change in Australia, it’s tempting to give in to despair. At the national level, following the abandonment of the National Energy Guarantee last year, we have no coherent energy policy and no serious policy to address climate change.

In this context, the announcement of two separate inquiries into the feasibility of nuclear power (by the New South Wales and federal parliaments) could reasonably give rise to cynicism. The only possible case for considering nuclear power, in my view, is that it might provide a way to decarbonise our electricity supply industry.

Yet many of the keenest boosters of nuclear power have consistently opposed any serious measure to address climate change, and quite a few have rejected mainstream science altogether.

Activists dressed as nuclear waste barrels protesting at the Lucas Heights nuclear reactor in 2001. Nuclear technology in Australia has long raised concern among environmentalists.
Laura Frriezer/AAP



Read more:
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Yet in a situation which all responsible people view as a climate emergency, we can’t afford the luxury of despair. For this reason, rather than dismissing these inquiries as political stunts, I made a submission to the federal inquiry setting out the conditions required to allow for any possibility of nuclear power in Australia.

The submission was picked up by the national media, which largely focused on my proposal to lift the state ban on nuclear power and implement a carbon price.

The reception from commentators on the right, who want the ban lifted, and from renewables advocates, who want a price on carbon, suggests a middle ground on nuclear power may be achievable.

The three big problems with nuclear power

Three fundamental problems arise immediately when considering the prospect of nuclear power in Australia. First, the technology is expensive: more expensive than new fossil-fuelled power stations, and far too expensive to compete with existing fossil fuel generators under current market conditions.

Second, given the time lags involved, any substantial contribution from nuclear power in Australia won’t be available until well beyond 2030.

Third, given the strong public opposition to nuclear power, particularly from the environmental movement, any attempt to promote nuclear power at the expense of renewables would never get broad support. In these circumstances, any investor in nuclear power would face the prospect of losing their money the moment the balance of political power shifted.

A technician uses a hot cell which shields radioactive material at the Opal nuclear research reactor at Lucas Heights in Sydney.
Tracey Nearmy/AAP

On the first point, we have some evidence from the contract agreed by the UK government in for the construction of the Hinkley C nuclear power plant. This was the first new nuclear construction project to be approved in an OECD country for a number of years.

The agreement to construct Hinkley was based on a guaranteed “strike price” of £92.50/ megawatt hours (MWh), in 2012 prices, to be adjusted in line with the consumer price index during the construction period and over the subsequent 35-year tariff period. At current exchange rates, this price corresponds to approximately A$165.




Read more:
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Prices in Australia’s National Electricity Market have generally averaged around A$90/MWh. This implies that, if new nuclear power is to compete with existing fossil fuel generators, a carbon price must impose a cost of A$75/MWh on fossil fuel generation.

Assuming emission rates of 1.3 tonnes/MWh for brown coal, 1 tonne/MWh for black and 0.5 tonnes for gas, the implied carbon price ranges from A$50/tonne (to displace brown coal) to $150/tonne (to displace gas). On the basis that nuclear power is most plausible as a competitor for baseload generation from brown coal, I considered a price of A$50/tonne.

A blueprint for reform

The central recommendations of my submission were as follows:

Nuclear power, while costly, could dramatically reduce Australia’s electricity sector emissions.
AAP

Recommendation 1: A carbon price of A$25/tonne should be introduced immediately, and increased at a real rate of 5% a year, reaching A$50/tonne by 2035.

Recommendation 2: The government should immediately adopt the recommendations of its own Climate Change Authority for a 40% to 60% reduction in emissions by 2030, relative to 2000 levels, and match other leading OECD countries in committing to complete decarbonisation of the economy by 2050.

Recommendation 3: The parliament should pass a motion:

  • affirming its confidence in mainstream climate science and its acceptance of the key conclusions of the United Nations’ Intergovernmental Panel on Climate Change;
  • legislating a commitment to emissions reductions;
  • removing the existing ban on nuclear power.

Let’s all meet in the middle

Rather to my surprise, this proposal received a favourable reception from a number of centre-right commentators.

Reaction from renewables proponents, on social media at least, was cautious. But it did not indicate the reflexive hostility that might be expected, given the polarised nature of the debate.

There are immediate political implications of my proposal at both the state and federal level. It will be more difficult for the Coalition-dominated committees running the two inquiries to bring down a report favourable to nuclear power without addressing the necessary conditions – including a carbon price. If the government’s hostility to carbon pricing is such that a serious proposal for nuclear power cannot be considered, it will at least be clear that this option can be abandoned for good.

Former Nationals leader and now backbencher Barnaby Joyce is a strong advocate for nuclear power.
Lukas Coch/AAP

In the admittedly unlikely event that the Coalition government shows itself open to new thinking, the focus turns to Labor and the Greens.

Given the urgency of addressing climate change – a task that is best addressed through a carbon price – it makes no sense to reject action now on the basis that it opens up the possibility of nuclear power sometime in the 2030s. And, if renewables and storage perform as well as most environmentalists expect, nuclear power will be unable to compete even then.

Political hardheads will doubtless say that this is all impossible, and they may be right. But in a world where Donald Trump can win a US presidential election, and major investment banks support UK Labour leader Jeremy Corbyn over Prime Minister Boris Johnson, “impossible” is a big claim

In the absence of any prospect of progress on either energy or climate, the grand bargain I’ve proposed is at least worth a try.The Conversation

John Quiggin, Professor, School of Economics, The University of Queensland

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

Will a vegetarian diet increase your risk of stroke?



This is the first study to link a vegetarian diet to an increased risk of stroke. But the evidence isn’t strong enough to cause alarm.
From shutterstock.com

Evangeline Mantzioris, University of South Australia

Research Checks interrogate newly published studies and how they’re reported in the media. The analysis is undertaken by one or more academics not involved with the study, and reviewed by another, to make sure it’s accurate.

A UK study finding vegetarianism is associated with a higher risk of stroke than a meat-eating diet has made headlines around the world.

The study, published in the British Medical Journal last week, found people who followed vegetarian or vegan diets had a 20% higher risk of having a stroke compared to those who ate meat.

But if you’re a vegetarian, there’s no need to panic. And if you’re a meat eater, these results don’t suggest you should eat more meat.

While we don’t fully understand why these results occurred, it’s important to note the study only showed an association between a vegetarian diet and increased stroke risk – not direct cause and effect.




Read more:
Clearing up confusion between correlation and causation


What the study did and found

The researchers looked at 48,188 men and women living in Oxford, following what they ate, and whether they had heart disease or a stroke, over 18 years. The researchers grouped the participants according to their diets: meat eaters, fish eaters (pescatarians) and vegetarians (including vegans).

While vegan diets are quite different to vegetarian diets, the investigators combined these two groups as there were very small numbers of vegans in the study.

In their analysis, the researchers accounted for variables which are known risk factors for heart disease and stroke, including education level, smoking status, alcohol consumption, and physical activity.




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They found vegetarians had a 22% lower risk of heart disease than meat eaters. This is equivalent to ten fewer cases of heart disease per 1,000 vegetarians than in meat eaters over ten years.

Yet the vegetarians had a 20% higher rate of stroke, equivalent to three more strokes per 1,000 vegetarians compared to the meat eaters over ten years.

The decrease in heart disease risk seemed to be linked to lower body mass index (BMI), cholesterol levels, incidence of diabetes, and blood pressure. These benefits are all known to be associated with a healthy vegetarian diet, and are protective factors
against heart disease.

This study showed fish eaters (who did not consume meat) had a 13% lower risk of heart disease, but no significant increase in the rate of stroke when compared to meat eaters.

As with any study, there are strengths and weaknesses

The main strength of this study is that it closely followed a very large group of people over a long period of time.

The major weakness is that being an observational study, the researchers were not able to determine a cause and effect relationship.

So this study is not showing us vegetarian diets lead to increased risk of stroke; it simply tells us vegetarians have an increased risk of stroke. This means the association may be linked to other factors, aside from diet, which may be related to the lifestyle of a vegetarian.

The study’s authors suggest a difference in vitamin B12 levels between the vegetarian and meat-eating groups may have contributed to the results.
From shutterstock.com

And while vegetarian and vegan diets may be seen as generally healthier, vegetarians still may be eating processed and ultra-processed foods. These foods can contain high levels of added salt, trans fat and saturated fats. This study did not report on the whole dietary pattern – just the major food groups.

Another major weakness of this study is that vegans and vegetarians were grouped together. Vegetarian and vegan diets can vary considerably in nutrient levels.

So why would the vegetarian group have a higher stroke risk?

These kind of observational studies are unable to provide what scientists call “a mechanism” – that is, a biological explanation as to why this association may exist.

But researchers will sometimes offer a potential biological explanation. In this case, they suggest the differences in nutrient intakes between the different diets may go some way to explaining the increased risk of stroke in the vegetarian group.

They cite a number of Japanese studies which have shown links between a very low intake of animal products and an increased risk of stroke.




Read more:
Eat your vegetables – studies show plant-based diets are good for immunity


One nutrient they mention is vitamin B12, as it’s found only in animal products (meat, fish, dairy products and eggs). Vegan sources are limited, though some mushroom varieties and fermented beans may contain vitamin B12.

Vitamin B12 deficiency can lead to anaemia and neurological issues, including numbness and tingling, and cognitive difficulties.

The authors suggest a lack of vitamin B12 may be linked to the increased risk of stroke among the vegetarian group. This deficiency could be present in vegetarians, and even more pronounced in vegans.

But this is largely speculative, and any associations between a low intake of animal products and an increased risk of stroke remain to be founded in a strong body of evidence. More research is needed before any recommendations are made.

What does this mean for vegetarians and vegans?

Vegetarians and vegans shouldn’t see this study as a reason to change their diets. This is the only study to date to have shown an increased risk of stroke with vegetarian or vegan diets.

Further, this study has shown overall greater benefits are gained by being vegetarian or vegan in its association with reduced risk of heart disease.

Meanwhile, other studies have shown meat eaters – particularly people who eat large amounts of red and processed meats – have higher risk of certain cancers.




Read more:
Are there any health implications for raising your child as a vegetarian, vegan or pescatarian?


Whether you’re an omnivore, pescatarian, vegetarian or vegan, it’s important to consider the quality of your diet. Focus on eating whole foods, and including lots of vegetables, fruits, cereals and grains.

It’s equally important to minimise the intake of processed foods high in added sugars, salt, saturated and trans fats. Diets high in these sorts of foods have well-established links to increased risk of heart disease and stroke. –Evangeline Mantzioris


Blind peer review

The analysis presents a fair and balanced assessment of the study, accurately pointing out that no meaningful recommendations can be drawn from the results. This is particularly so since the majority of the data was collected via self-reported questionnaires, which reduces the reliability of the results.

While in many cases the media has reported an increased stroke risk in vegetarians, total stroke risk was not actually statistically different between the groups. The researchers looked at two types of stroke: ischaemic stroke (where a blood vessel supplying blood to the brain is obstructed) and haemorrhagic stroke (where a blood vessel leaks or breaks).

A statistically significant increased risk in the vegetarian group was only seen in haemorrhagic stroke – and even there it’s marginal. Statistically, and in total numbers of people affected, the reduced heart disease risk in the vegetarian group is more convincing. –Andrew CareyThe Conversation

Evangeline Mantzioris, Program Director of Nutrition and Food Sciences, University of South Australia

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

Can we heal teeth? The quest to repair tooth enamel, nature’s crystal coat



The enamel on your teeth is what makes them sparkle. It also acts as a protective coating on the teeth.
From shutterstock.com

Arosha Weerakoon, The University of Queensland

Tooth enamel is one of the hardest tissues in the human body. It acts as a protective layer for our teeth, and gives our smile that pearly white shimmer. But when enamel erodes, it can’t regrow itself.

In a significant scientific breakthrough, researchers recently discovered a way to regrow human tooth enamel.

Scientists from China have invented a gel that contains mineral clusters naturally found in teeth. In partially acid-damaged teeth, the gel stimulates crystal regrowth to restore tooth enamel back to its original structure.

While the method is yet to be tested on people, one day this could mean saying goodbye to painful needles, the dreaded dentist drill, and even fillings.




Read more:
How often should I get my teeth cleaned?


What is tooth enamel?

Enamel is the outermost layer of our teeth, and protects our pearly whites from wear and tear. It also insulates us from feeling pain and sensitivity.

When this protective coat erodes, our teeth soften and become vulnerable to developing cavities (holes in the teeth) which may require dental treatment such as fillings.

Enamel is the protective outer layer of our teeth.
From shutterstock.com

Tooth enamel contains the same minerals, calcium and phosphate, found in bone. Unlike bone though, enamel contains relatively more mineral, and enamel crystals are arranged in a complex geometrical pattern.

Under a microscope, enamel crystals are shaped like long ribbons, or spaghetti strands. These crystal strands are assembled into clusters, like packets of dry spaghetti, orientated at 60 degrees to each other. The ribbon clusters, which weave together like honeycomb, are known as rods and inter-rods.

When destroyed, this weave is difficult to recreate, because the cells that form enamel die as our teeth emerge from our gums.

Why does our tooth enamel erode?

While enamel is very hard, it’s also brittle and susceptible to erosion. This occurs when tooth mineral dissolves into our saliva.

Our saliva is constantly trying to balance any “bad guys” it encounters with “good guys” at its disposal. When we get acid in our mouth (a bad guy) the mineral in our saliva (a good guy) tries to bind to it to neutralise the acid, and prevent it from causing harm. This is known as buffering.

If there’s too much acid, or the quality and quantity of our saliva is inadequate, we run out of mineral to buffer the “acid attack”. So in a final effort to neutralise the acidity in our mouth, the mineral in our teeth will dissolve into our saliva. This is when our teeth erode and become vulnerable.




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Like the erosion we see in our beaches and river beds, under a microscope, eroded enamel surfaces appear moth-eaten and uneven. This is because erosion destroys the crystal organisation I described above.

Current dentist-recommended products repair enamel but cannot regrow the complex crystal structure to recreate a pearly white shimmer. This is why globally, the dental community are very excited about this research.

Can we control erosion?

Our teeth erode when we eat and drink foods rich in acid, including wine, cola beverages, fruit juices, sour lollies, and energy and sports drinks. As a general rule, anything that tastes sour is high in acid. It’s best to avoid or limit acidic food and drinks where possible.

People with medical conditions such as bulimia or acid reflux may be at greater risk of their teeth eroding. If you suffer from these conditions, in addition to getting help from your doctor, it’s best to seek regular dental check-ups.

We know lollies aren’t good for teeth. But sour lollies in particular contain acid, which contributes to erosion.
From shutterstock.com

When our enamel erodes, it makes our teeth appear yellower. Often, we may also experience toothache or sensitivity because we’ve lost the enamel’s natural insulation.

If your teeth are eroding, a dentist and/or dental hygienist will be able to monitor and help you manage your oral health. In addition to brushing and cleaning between your teeth, your dental professional may also recommend:

  • rinsing with a bicarbonate and salt water mouthwash
  • chewing sugar-free gum to stimulate an increase in mineral-rich saliva
  • using a dentist-recommended toothpaste, special cream and/or mouthwash to help replace lost mineral and repair your teeth
  • delaying cleaning your teeth after an “acid attack” to prevent removing softened enamel.



Read more:
Two million Aussies delay or don’t go to the dentist – here’s how we can fix that


How did the scientists regrow enamel?

In a lab, extracted teeth were treated with acid to simulate erosion, then painted with a special gel. This gel contained calcium phosphate ion clusters – mineral clusters naturally found in teeth – mixed with an ingredient called triethylamine
(TEA).

After two days in a simulated mouth-like environment, the previously eroded enamel was checked for crystal growth, size, shape, organisation and composition using special microscopes.

The spaghetti-like crystals had regrown seamlessly, and the crystal clusters had correctly orientated themselves to form the rod and inter-rod honeycomb weave.

When will we be able to regrow enamel?

While this technology is something to look forward to, the short answer for now is “not yet”. This study has only been performed on extracted teeth. The researchers are hoping to test their method on mice, and then people soon after.

One of the significant limitations to moving towards animal and human trials is the toxicity of the essential ingredient, TEA. Another challenge is the enamel thickness they were able to repair was at a microscopic level.




Read more:
Health check: what’s eating your teeth?


But all is not lost. The scientists hope to find a safe way to use TEA with the intention of growing enamel thick enough to fix larger sections of eroded enamel.

For now, the thought of not having to get fillings at the dentist is an exciting prospect on the horizon. So watch this space.The Conversation

Arosha Weerakoon, Lecturer, General Dentist & PhD Candidate, The University of Queensland

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

Here’s what you can eat and avoid to reduce your risk of bowel cancer



It’s not certain why, but fibre has protective effects against bowel cancer.
http://www.shutterstock.com

Suzanne Mahady, Monash University

Australia has one of the highest rates of bowel cancer in the world. In 2017, bowel cancer was the second most common cancer in Australia and rates are increasing in people under 50.

Up to 35% of cancers worldwide might be caused by lifestyle factors such as diet and smoking. So how can we go about reducing our risk of bowel cancer?




Read more:
What’s behind the increase in bowel cancer among younger Australians?


What to eat

Based on current evidence, a high fibre diet is important to reduce bowel cancer risk. Fibre can be divided into 2 types: insoluble fibre, which creates a bulky stool that can be easily passed along the bowel; and soluble fibre, which draws in water to keep the stool soft.

Fibre from cereal and wholegrains is an ideal fibre source. Australian guidelines suggest aiming for 30g of fibre per day for adults, but fewer than 20% of Australian adults meet that target.

Wheat bran is one of the richest sources of fibre, and in an Australian trial in people at high risk of bowel cancer, 25g of wheat bran reduced precancerous growths. Wheat bran can be added to cooking, smoothies and your usual cereal.

It’s not clear how fibre may reduce bowel cancer risk but possible mechanisms include reducing the time it takes food to pass through the gut (and therefore exposure to potential carcinogens), or through a beneficial effect on gut bacteria.

Once bowel cancer is diagnosed, a high fibre diet has also been associated with improved survival.

Dairy is ‘probably’ protective against bowel cancer.
from http://www.shutterstock.com



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Milk and dairy products are also thought to reduce bowel cancer risk. The evidence for milk is graded as “probably protective” in current Australian bowel cancer guidelines, with the benefit increasing with higher amounts.

Oily fish may also have some protective elements. In people with hereditary conditions that make them prone to developing lots of precancerous growths (polyps) in the bowel, a trial where one group received a daily supplement of an omega 3 polyunsaturated fatty acid (found in fish oil) and one group received a placebo, found that this supplement was associated with reduced polyp growth. Whether this is also true for people at average risk of bowel cancer, which is most of the population, is unknown.

And while only an observational study (meaning it only shows a correlation, and not that one caused the other), a study of bowel cancer patients showed improved survival was associated with daily consumption of coffee.

What to avoid

It’s best to avoid large quantities of meat. International cancer authorities affirm there is convincing evidence for a relationship between high meat intake and bowel cancer. This includes red meat, derived from mammalian muscle such as beef, veal, lamb, pork and goat, and processed meat such as ham, bacon and sausages.

Processed meats have undergone a preservation technique such as smoking, salting or the addition of chemical preservatives which are associated with the production of compounds that may be carcinogenic.

Evidence also suggests a “dose-response” relationship, with cancer risk rising with increasing meat intake, particularly processed meats. Current Australian guidelines suggest minimising intake of processed meats as much as possible, and eating only moderate amounts of red meat (up to 100g per day).

What else can I do to reduce the risk of bowel cancer?

The key to reducing cancer risk is leading an overall healthy lifestyle. Adequate physical activity and avoiding excess fat around the tummy area is important. Other unhealthy lifestyle behaviours such as eating lots of processed foods have been associated with increased cancer risk.

And for Australians over 50, participating in the National Bowel Cancer Screening program is one of the most effective, and evidence-based ways, to reduce your risk.




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INTERACTIVE: We mapped cancer rates across Australia – search for your postcode here


The Conversation


Suzanne Mahady, Gastroenterologist & Clinical Epidemiologist, Senior Lecturer, Monash University

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

In the Democrats’ bitter race to find a candidate to beat Trump, might Elizabeth Warren hold the key?



She’s sitting third on the list of Democratic nomination contenders, but might Elizabeth Warren ultimately be the person to beat Donald Trump?
EPA/AAP/Craig Lassig

Dennis Altman, La Trobe University

Conservative former congressman Joe Walsh recently announced he would challenge Donald Trump for the Republican Party’s 2020 Presidential nomination.

Challenging an incumbent president is not new: both Gerald Ford and Jimmy Carter faced very significant challenges when they sought a further term. But Trump’s hold on Republicans suggests that no challenge is likely to succeed.

For the Democrats, however, the race to oppose Trump is now wide open and bitter.

The American political system allows participation through primary elections in ways unknown in our tightly controlled party system.




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Two dozen candidates, one big target: in a crowded Democratic field, who can beat Trump?


Millions of voters take part in choosing the candidate of their party. This can have strange consequences; some of Bernie Sanders’ supporters were so disaffected by the nomination of Hillary Clinton that perhaps 10% of them voted for Trump.

Candidates must damage their opponents without providing ammunition that can be used against their party in the November elections.

Presidential primaries stretch across the first half of 2020. These include several key contests determined by caucuses, which involve actual attendance for several hours to register one’s choice. Because Iowa traditionally leads off, huge attention is paid to the results there.

Iowa is a state with a population of just over 3 million, and is far whiter than the United States. Its caucuses are followed by three other small states: New Hampshire, Nevada and South Carolina, which between them start to look like the country as a whole.

Every Democratic candidate is spending time and resources in the early states, with teams of volunteers criss-crossing the small towns of Iowa and New Hampshire and wooing minority communities in Nevada (Hispanic) and South Carolina (African-American).

By the end of February, expect the field to have shrunk from the current dozen or so serious contenders to about half that number. On March 3 comes a slew of votes across 16 states, including California and Texas. The results that day will either produce a clear front runner or a dogged three-way fight lasting three more months.

One of the oddities of the Democratic race so far is that the two leading candidates and the incumbent president are all white men in their seventies, well past the accepted American retirement age.

The two best known Democratic contenders are Senator Bernie Sanders and former Vice President Joe Biden, who cover the ideological spectrum of the Democratic Party: Sanders on the left and Biden on the right. Both entered the race with considerable money and name recognition, and both have started slipping in the polls as younger candidates have gained attention.

Some current polls now place Senator Elizabeth Warren of Massachusetts as equalling their support. Warren shares some of Sanders’ radical positions on health care and taxation, but she is careful to not define herself as a socialist, and she has the same grasp of policy as did Hillary Clinton.

Trump would undoubtedly campaign against Warren as another effete east coast liberal, invoking the failure of two previous candidates from Boston, Michael Dukakis and John Kerry.

Democrat voters looking for someone younger and different may swing behind Senator Kamala Harris from California, a former Attorney-General who is positioning herself as someone who transcends both racial and gender prejudices.

Kamala Harris is another Democratic runner polling well.
AAP/EPA/Elijah Nouvelage

Polls in Iowa and New Hampshire show Harris and Pete Buttigieg as the only other candidates who consistently poll over 10%. Buttigieg is the unexpected dark horse: gay, young, ex-military and mayor of South Bend, Indiana, which is smaller than Geelong. He far outpolls more experienced candidates – one of them, Kirsten Gillibrand, has already withdrawn.




Read more:
US Democratic presidential primaries: Biden leading, followed by Sanders, Warren, Harris; and will Trump be beaten?


The candidates are united in their dislike of Donald Trump, but this is a battle of egos and ideologies. Do the Democrats seek to win over Trump supporters in key states by appealing to a mythical “centre”? Do they try to win over Republicans, particularly educated women who made up some of the base for their victories in last year’s House of Representatives election? Or do they concentrate on their potential supporters among the young and minority communities who are less likely to vote?

In a country where fewer than 60% of those eligible bother to vote, the last option would seem the most viable, but that requires candidates who can speak to the disinterested and the disenfranchised.

Both racism and sexism played a role in Trump’s victory, and Biden’s current lead in the polls suggests many Democrats feel an older white man is their safest choice. But if the Democrats are to galvanise young and minority voters to turn out they need a candidate who is clearly very different to Trump.

The electoral college system means that winning the popular vote, as Clinton did, does not guarantee victory. In key mid-western industrial states the vote may well be determined by the consequences of Trump’s current economic policies.

Much can change before Democratic supporters start declaring their choice in six months. Several of the also-rans may surprise us; maybe one of the front-runners will drop out.

Were Bernie Sanders to withdraw and throw his support to Elizabeth Warren, she would become the front-runner; it’s less clear where Biden’s supporters would go, but if he polls poorly in February, he is likely to fade away.

At this point in 2015, pundits were predicting a presidential race between Clinton and Jeb Bush, with Clinton favoured to win. Nothing in politics is predictable.The Conversation

Dennis Altman, Professorial Fellow in Human Security, La Trobe University

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