I’m not overweight, so why do I need to eat healthy foods?



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No, being thin doesn’t mean you can live off junk food.
from http://www.shutterstock.com

Alessandro R Demaio, University of Copenhagen

We all have that one friend whose eating habits and body shape simply don’t add up. While enjoying the unhealthiest of meals and a sedentary lifestyle, somehow they effortlessly retain a slender figure.

At first glance we may assume these slim people are healthy, but it’s not always the case. So if you don’t have weight to worry about, what’s the impetus for avoiding sweet or salty temptations and eating good, nutritious foods instead?

Healthy weight ≠ good health

Body mass index or BMI, the tool most often used to determine “healthy weight ranges”, was designed primarily to track the weight of populations.

While it’s a simple and useful screening tool when looking at groups of people, it’s not a good marker of individual health. This is because BMI is a measure of our height and our weight, and the ratios of their combination. But weight alone doesn’t discriminate between a kilogram of fat versus a kilogram of muscle nor does it account for body shape and fat distribution differences relating to, say, ethnicity or gender.




Read more:
Viewpoints: can you be healthy at any weight?


Just as not all obese individuals have heart disease risk factors or unhealthy metabolisms (the conversion of food into energy), nor do all lean people have healthy ones.

There’s a well-documented subset of people known as metabolically obese, normal weight individuals. These people are not obese as determined by their height and weight, but may face metabolic dysfunction such as insulin resistance (which leads to a build-up of sugar in the blood), and like their physically obese counterparts are predisposed to type 2 diabetes, high levels of fats in the blood, heart disease and even some cancers.

Food is health

The most compelling reason to eat healthy foods is the correlation between good nutrition and well-being. Coupled with regular exercise, eating a diet rich in whole foods and grains, healthy oils and low in sugar and salt, has been shown to convey a number of benefits. These include a longer life with less pain and suffering, less risk of back pain or muscular problems and even an increased libido.




Read more:
We all have to die of something, so why bother being healthy?


Studies from around the world also show people with healthy diets are less likely to experience depression while unhealthy diets may put individuals at an increased risk of depression.

People with nutritious diets are less likely to be depressed.
from http://www.shutterstock.com

Food has been identified as an important risk factor for cognitive decline and dementia in older age.

A healthy diet combined with physical activity can strengthen bones and reduce body aches and pains. And these benefits are conferred irrespective of your baseline weight or age.

Health risks aren’t always visible

While it might be easy to take solace in a thinner weight, many of the serious health risks associated with poorer diet are often hidden from plain sight.

Excessive salt consumption can cause the kidneys to hold on to more water, resulting in an increase in blood pressure. High blood pressure strains the arteries that supply blood to our vital organs including our heart and brain, and increases our risk of stroke, dementia, heart attack and kidney disease.

Consumption of high amounts of sugar, especially from sugar sweetened beverages, is associated with an increased risk in fatty liver disease, among many other health problems. This in turn significantly increases our risk of liver scarring, heart disease and stroke.

Recent research has also reconfirmed a link between bowel cancer and red meat consumption. Processed meats such as ham, bacon and salami appear to be especially problematic.

Not only can all of these occur without any visual cues, but they can also develop irrespective of our weight.

Our kids’ health

The importance of a good diet is not just limited to our own health. Children of parents with poor diets are significantly more likely to inherit similarly unhealthy eating habits.

And it doesn’t stop there. Through a mechanism called epigenetics, our health and our diet can result in alterations to the expression of our genes.

We pass our habits on to our kids. Make them good ones.
from http://www.shutterstock.com

Animal studies have shown epigenetic changes resulting from poor diet (and other stressors) can influence the healthiness of future generations. Many scientists now believe the same will prove true for humans too.




Read more:
Childhood obesity: are parents really to blame?


Saving lives, and money

Contrary to what many of us think, the latest evidence suggests eating a healthy diet is actually cheaper than consuming the unhealthy foods that now dominate many Australian households.

Analysis of both wealthier and poorer suburbs in Brisbane, for example, showed the average family of four spends 18% more on current diets than would be required if they could more closely adhere to healthy dietary recommendations.

This is not to say eating healthily is easy, accessible or even possible for everyone, but might be more possible than we first think.

Not only would adopting a healthy diet be a beneficial investment for individuals and families, it might also go a long way to curbing the major societal costs from growing weight gain. The annual costs from obesity already add up to A$830 million in Australia alone.

The consequences of poor diet increasingly burden Australians and our health care system. While it’s easy to measure our health based on a reading of the bathroom scales, eating a diverse and nutritious diet will bring overwhelming benefits to everyone – regardless of our current weight.


The ConversationThomas Goodwin contributed to the research and writing of this article.

Alessandro R Demaio, Australian Medical Doctor; Fellow in Global Health & NCDs, University of Copenhagen

This article was originally published on The Conversation. Read the original article.

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How to keep school lunches safe in the heat



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Keep it cool.
Shutterstock/bitt24

Vincent Ho, Western Sydney University


This article is part of a series that draws on the latest research on back to school transitions. In it, experts explain how best to prepare children for school, and counter difficulties such as stress or bad behaviour.


The school holidays are over but summer isn’t, and we’re bound to have more hot days before the season ends. So how can you avoid making yourself or your kids sick when packing picnics or school lunches in the heat?

The good news is that the bacteria that cause food to spoil are quite different to the bacteria that typically cause food poisoning, and generally don’t make you sick.

But harmful bacteria that cause food poisoning can still end up in lunchboxes and picnics. Controlling the temperature of the food can help minimise the chance of getting sick, or the severity of any food-borne illness.

Food poisoning and spoiling

When left out in the heat, foods such as meat, cheese, fish and milk will spoil and start to smell because of bacteria such as Pseudomonas. But while it’s certainly not a good idea for your child to nibble on spoiled foods, such bacteria don’t usually result in gastrointestinal symptoms.




Read more:
Salmonella in your salad: the cost of convenience?


On the other hand, more than four million Australians get food poisoning each year. The bacteria responsible for the majority of cases – Salmonella, Campylobacter, Staphylococcus aureus, E. coli and Listeria– usually come from animal faeces and soil. They don’t change the appearance, smell or taste of food.

The contaminated food can cause symptoms such as nausea, diarrhoea, vomiting, abdominal cramps and chills as soon as 30 minutes after ingestion.

The cause of a specific food poisoning case can be hard to determine. Often the contaminated food is completely consumed and mild cases of diarrhoea can easily be caused by exposure to irritants such as gluten or lactose, as by a toxin, bacteria or virus. It’s usually only when multiple people eating the same food get sick that the source is traced and investigated.

Bacteria flourish in the heat

As with almost any kind of infection, contact with disease-causing bacteria doesn’t inevitably result in disease. We regularly handle a low level of bacterial contamination in the foods we eat without coming to harm. A gram of fresh tofu may contain from 300 to 100,000 bacteria and fermented foods such as miso or yoghurt may contain millions of bacteria per gram.

The number of bacteria in contaminated food is important: a person ingesting a higher amount of virulent bacteria is more likely to fall ill than someone ingesting a much smaller amount. The type of bacteria is also important, as more virulent strains can lead to illness in lower doses.

Yoghurt can contain millions of bacteria per gram.
Upupa4me, CC BY-SA

These bacteria flourish in a zone between 5 and 60 degrees Celsius – known as the temperature “danger zone” – where bacterial reproduction is most rapid.

In the summer heat, the doubling time of bacteria can be as short as 20 minutes. This means a thin slice of a well-washed tomato with 100 bacteria at 8am could contain just over 26 million bacteria by 2pm on the same day.

Storing foods outside the temperature danger zone can dramatically slow the rate at which bacteria can multiply. This is why cold food should be kept below 5 degrees Celsius and hot foods above 60 degrees.




Read more:
Monday’s medical myth: leave leftovers to cool before refrigerating


What can you do?

There are four key steps to safely preparing food:

1) Wash your hands thoroughly before handling food. Use clean utensils and cutting boards

2) Use separate cutting boards for fresh produce and raw meat or poultry to reduce the risk of Salmonella

3) Cook food to the right temperature using a food thermometer

4) Chill perishable foods such as meats, eggs, cheese or yoghurt with at least two cold sources, such as freezer packs, to keep harmful bacteria from multiplying rapidly. Frozen juice poppers can also be used as freezer packs and by lunchtime should be thawed and ready to drink.

An insulated lunchbox should be used for packing perishable foods. Insulated containers such as thermos flasks can also be used to store hot soups and stews.
When packing a child’s lunch the night before, store the food in the refrigerator overnight, so it stays colder for longer.

Finally, teach children to wash their hands with soapy water for 20 seconds before eating. Or pack disposable wipes so they can easily clean their hands before and after eating.




Read more:
Monday’s medical myth: you have to wash with hot water to kill bugs


Getting sick

Despite parents’ best efforts, food poisoning can occur. When it does, oral rehydration is the cornerstone of treatment. You can buy a rehydrating solution of sugar, salt and water from most pharmacists. Or make your own by adding half a level teaspoon of salt and six level teaspoons of sugar dissolved in one litre of clean drinking or boiled water.

A bland diet for a short period of time can be helpful in recovery.

The ConversationFor severe symptoms or for any concerns about your child’s recovery, see your GP.

Vincent Ho, Senior Lecturer and clinical academic gastroenterologist, Western Sydney University

This article was originally published on The Conversation. Read the original article.

Why the difficult person at work probably isn’t a psychopath



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Our workplace and work processes may be contributing to stress and bad behaviour.
shutterstock

Katarina Fritzon; Joanna Wilde, Aston University, and Rosalind Searle, University of Glasgow

As workplaces become increasingly difficult and damaging environments, there are plenty of articles and books on dealing with “psychopaths” among your colleagues.

But psychopathy is heavily contested as a diagnostic category. And labelling a coworker a psychopath fails to account for how our workplaces can encourage bad behaviour.

From an “always on” work culture to badly designed work practices, there are many reasons why a colleague could be behaving badly. This is partly why clinicians are prohibited from diagnosing someone from afar – there may be many other factors influencing the behaviour.




Read more:
Psychopaths versus sociopaths: what is the difference?


The research on criminal psychopathy is based on thousands of cases and involves statistical prediction of future actions based on these cases. The articles that set out how to tell if your boss is a psychopath simply do not have the same evidence base.

Of the 20 criteria used to assess criminal psychopathy, many do not translate to the workplace (other measures have not been tested in work environments either).

What about the workplace?

As we have seen in recent sexual harassment scandals in media and politics, when workplaces don’t punish employees for unacceptable or harmful behaviour it gives tacit permission, in effect encouraging it to continue.

Individuals behaving badly are often oblivious to the impact they are having, and so without proper sanctions and containment remain unaware of the need to self-correct. But there are also specific aspects of our workplaces that may contribute to such problematic behaviour.

People’s personalities aren’t fixed, which means that some human resources tools, such as testing for “emotional intelligence” (also known as EQ), may actually incentivise people to become more skilful at manipulating others’ emotions.

If someone is hired or promoted because they are very good at impression management and manipulation, they are likely to be very effective at making their managers believe they are doing a good job while also bullying their peers and subordinates.




Read more:
Emotionally intelligent employees may come with a dark side – manipulation


Badly designed workplaces, including excessive demands, poor physical environment, unfair practices and a lack of social support, can produce stress in employees.

For example, ill-conceived human resources processes, including performance management, can undermine social relations.

As a result, coworkers’ coping strategies (including changing the way we think about a situation, using humour, or focusing on solving problems) become overwhelmed. This leaves them less able to attend to the day-to-day normal pressures of work, and to regulate their own social behaviours effectively.

In other words, bad behaviour in the workplace could be linked to fatigue, rather than to an aspect of a person’s character.

Distress caused by difficult social contexts can also lead to “dissociation”. Dissociation is a self-protective mechanism that enables people to cut themselves off from their feelings of distress. But it can be experienced by others as coldness or a lack of empathy.




Read more:
Understanding others’ feelings: what is empathy and why do we need it?


Instead of miscategorising these distressed people as psychopathic, we need to better understand and recognise early indicators of reactions that need care.

To be accurately used in a workplace, the term “psychopathy” would require collecting data on thousands of cases of employees and examining variables that predict, for example, bullying, harassment, fraud, and other counterproductive work behaviours. This research does exist, but it is preliminary and needs replication with much larger samples.

But more profoundly, this distracts us from what we should be doing: making our workplaces better places to be. This will come from careful attention to the way that structures and practices feed unfairness and bring out the worst in us.

Instead of developing new ways of scapegoating each other with psychological concepts, we need to create environments that take care of our need to belong and to be appreciated for our contributions.

And finally, if you are really drawn to labelling a colleague a psychopath, you should perhaps also consider the question “is it me?”. There is substantial psychological evidence that judgement about the actions of others are usually harsher than our judgement of our own actions – even when they are the same actions.

The ConversationLabelling someone a psychopath makes the issue about the individual, rather than focusing on what the organisational factors are that are contributing to the behaviour.

Katarina Fritzon, Associate Professor of Psychology; Joanna Wilde, Industrial Fellowship, Aston University, and Rosalind Searle, Professor of HRM and organisational Psychology, University of Glasgow

This article was originally published on The Conversation. Read the original article.

How to understand and harness your workplace rage



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It’s ok to let a little anger show in the workplace but you shouldn’t let it all out, research says.
http://www.shutterstock.com

Peter O’Connor, Queensland University of Technology

As you’re sitting there, about to throw an office chair, your temperature and heart rate rising, know that it isn’t all in vain.

Getting angry in your office does actually have a positive side. For example, anger can motivate you to respond to perceived injustice. It can also be useful in negotiations, with research showing angry negotiators tend to have better outcomes.

But it can also lead you to make poor decisions, say something you’ll regret and even make you more physically violent.


Read more: In defence of happiness: why emotional intelligence is key in the digital age


Given the mixed consequences of anger at work, you shouldn’t feel justified in hitting a fellow employee, but recent research suggests a little anger in moderation is alright.

Common anger triggers at work

The most common cause of workplace anger is being treated unjustly (77%), according to an early but influential Australian study. Researchers also found we don’t tolerate being the target of immoral behaviour like laziness or theft (23%) and being disrespected by our coworkers (20%).

More recently, researchers have suggested three main triggers of anger in the workplace:

  1. Feeling unjustly treated by others, particularly a supervisor or witnessing an injustice in your organisation (for example someone else being treated unfairly)

  2. When you feel like someone is messing with your goals or obstructing your plans. Lack of time or resources can also be the cause of deviant behaviour at work

  3. Interpersonal conflict, like personality clashes and differences in attitudes. Not only causing one but many people to be angry.

Is your blood boiling yet?

When anger is beneficial

The research evidence for the professional benefits of anger are mostly in relation to negotiation and leadership situations.

In studies of negotiation, people who expressed anger had better outcomes. However this is usually only when the angry party has the greater power, or when the recipient of the rage has poor alternatives to negotiating.

A 2016 study found anger in leaders can make them appear more powerful, yet less effective. Intense anger in leaders motivates their subordinates to increase their effort but also means they will be more deviant. Another study found that anger enhances performance, but only when followers have conscientious and agreeable personalities.

More generally, research finds anger has positive consequences at work when it’s expressed verbally, is of low intensity and when it’s a mad man rather than a woman.

Do some people just have a low boiling point?

Although most people will occasionally experience anger at work, some people seem to constantly be on edge.

For example, people who usually blow their top as opposed to getting only a little angry will be more likely to experience ongoing anger at work. These people are easily provoked.

People who are neurotic at work are also likely to be more angry because they have poor emotional regulation. People who show traits of psychopathy and low agreeableness are also more likely to express their anger at work, than others.

However these people tend to be more successful at work. But anger is probably not the cause of their success. It is more likely that anger is a side-effect of adaptive characteristics. For example competitive people are likely to be both successful and express anger more often.

Anger as a strategy

Since anger is beneficial in some instances, it raises the question: should employees strategically act out anger to bring about positive outcomes? Although some research supports this, other studies suggest caution.

For example one study demonstrated that faking anger in negotiations is detrimental to resolving the conflict. A better strategy than faking anger is actually to communicate it when it is real, but do so in a controlled manner (for example not being abusive but telling someone you’re mad).

There’s only one type of person who seems to be an exception to this advice: those high in the personality trait “machiavellianism”. Machiavellian employees are those who operate strategically and manipulatively at work in order to achieve their goals. They can be highly angry and are likely to use it, and aggression, strategically to enhance their success.

Tips for managing anger

Aside from making you very unpopular in the workplace, anger has been linked to high blood pressure and heart disease. Fortunately, there are things you can do to manage anger in the office.


Read more: Four signs you have high emotional intelligence


You don’t have to be a zen master to learn to regulate your emotions through mindfulness and emotional intelligence training. One simple strategy involves reducing arousal through deep, slow breathing. This type of training can also protect from stress which is a major source of anger. Although emotional regulation will not eliminate anger, it will reduce its intensity.

You can also go straight to the source of your rage and see if that can be changed instead. This is not easily done, however it can be best in the long run.

The ConversationOverall, the research seems to suggest merit to both expressing and controlling anger. It’s generally not a good idea to use anger as a strategy to manipulate, but when something makes you angry, feel free to express it – it might lead to positive outcomes.

Peter O’Connor, Associate Professor, Business and Management, Queensland University of Technology

This article was originally published on The Conversation. Read the original article.

Guilty about that afternoon nap? Don’t be. It’s good for you.



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Naps have many benefits, including improving memory, reaction times and mood
Sal/Flickr, CC BY

Nicole Lovato, Flinders University

You may be familiar with that feeling of overwhelming sleepiness during the mid-afternoon. It’s common, occurs whether you’ve eaten lunch or not, and is caused by a natural dip in alertness from about 1 to 3pm. So, if you find yourself fighting off sleep in the middle of the day and you’re somewhere where you can have a nap, then do it.

Taking the time for a brief nap will relieve the sleepiness almost immediately and improve alertness for several hours after waking. And there are many other benefits too.

Understanding why we nap

People nap for lots of reasons, some which are:

  • to catch up on lost sleep

  • in anticipation of sleep loss to avoid feeling sleepy later on

  • for enjoyment, boredom or to pass time.

Napping is relatively common. In fact, about 50% of us report taking a nap at least once per week.

Napping rates are greater in countries like Greece, Brazil and Mexico that have a culture of siesta, which incorporate “quiet time” in the early afternoon for people to go home for a nap. In such countries, up to 72% of people will nap as often as four times per week.




Read more:
Forget siestas, ‘green micro-breaks’ could boost work productivity


The perks of napping

Naps are not only beneficial because they make us feel less sleepy and more alert, but because they improve our cognitive functioning, reaction times, short-term memory and even our mood.

The benefits of having a nap are similar to those of drinking coffee.
Photo by Jakub Kapusnak on Unsplash

Our research (not yet published) has found those who regularly nap report feeling more alert after a brief nap in the afternoon when compared to those who only nap occasionally.

Another research group found that motor learning, which is where brain pathways change in response to learning a new skill, was significantly greater following a brief afternoon nap for regular nappers when compared to non-nappers.

In fact, the overall benefits of naps are similar to those experienced after consuming caffeine (or other stimulant medications) but without the side effects of caffeine dependence and possibly disrupted sleep at night time.




Read more:
Health Check: what are ‘coffee naps’ and can they help you power through the day?


How long should a nap be?

The amount of time you spend napping really depends on the time you have available, how you want the nap to work for you, and your plans for the coming night. Generally speaking, the longer a nap is, the longer you will feel rejuvenated after waking.

Long naps of one to two hours during the afternoon will mean you are less sleepy (and require less sleep) that night. This could mean it will take longer than usual to fall asleep.

A brief power nap is a great way to improve alertness.
from shutterstock.com

If you are planning to stay up later than usual, or if taking a little longer to fall asleep at bedtime is not bothersome, time your nap for about 1.5 hours. This is the length of a normal sleep cycle. You will experience deep sleep for about an hour or so followed by light sleep for the last half an hour.

Waking up during light sleep will leave you feeling refreshed and alert. However, waking during deep sleep will not. If you sleep too long and miss the light sleep at the end of a nap, chances are you will wake up feeling sluggish and drowsy. If you do experience feeling drowsy after a nap, don’t worry – this feeling is temporary and will go away after a while.




Read more:
Want to boost your memory and mood? Take a nap, but keep it short


Another option is to have a brief “power” nap. Brief naps of 10-15 minutes can significantly improve alertness, cognitive performance and mood almost immediately after waking. The benefits typically last for a few hours.

Power naps are great because you won’t experience any sluggish or drowsy feelings after waking. This is because you do not enter any deep sleep during this brief time.

Research suggests, a brief, early-to-mid-afternoon nap provides the greatest rejuvenation when compared to naps at any other time of the day. However, if you’re struggling to stay awake, a brief nap taken at any time can be help keep you alert.


The ConversationFurther reading: Did we used to have two sleeps instead of one? Should we again?

Nicole Lovato, Postdoctoral Research Fellow, Adelaide Institute for Sleep Health, Flinders University

This article was originally published on The Conversation. Read the original article.

The Sick Man of Europe is Sick Again


As I have watched with some interest and concern the happenings in Turkey, the former ‘Sick Man of Europe’ appears to me to be once again ‘sick.’ Perhaps not in the exact same manner as it was at the end of the Ottoman Empire, but sick none-the-less. The little man of Turkey who runs the show there needs to be dealt with in my opinion. He is the very image of a small character who wants to be something bigger but has nothing really going for him apart from some thuggish type of rule. Perhaps the Kurds will teach him a lesson or two as he seeks to impose his bombastic will on them yet again.

For Erdogan’s latest efforts of getting on the world stage visit:
https://www.theguardian.com/world/2018/jan/21/recep-tayyip-erdogan-kurds-syria-risky-gamble-could-quickly-turn-sour

Explainer: how does sunscreen work, what is SPF and can I still tan with it on?



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Sunscreen protects from skin cancer, burning and from the sun’s ageing effects.
PRONicki Dugan Pogue/Flickr, CC BY

Terry Slevin, Cancer Council Australia

Sunscreen use not only reduces the risk of skin cancer and sunburn, it also reduces the ageing effect of the sun.

But whenever summer rolls around, it’s easy to forget the basics – like, how should I apply sunscreen? How long should I wait after applying it to go in the sun, and how long can I stay in the sun with it on? And how does it work anyway?

How does sunscreen work ?

There are two main parts to all sunscreens. The active ingredient and the emulsion.

Sunscreens either absorb UV radiation or reflect it.
from shuttersrock.com

The active ingredient does the sun protection work. These come in two categories: UV absorbers and UV reflectors.

UV absorbers are chemicals that absorb UV radiation and convert it to a very low level of heat. So low most don’t notice it, but a small proportion of people do report sunscreens make them feel uncomfortably warm.

UV absorber chemicals are also called “organic”, because they contain carbon atoms, a basis for all organic matter.

Some absorb the UVB part of the spectrum, which is known to cause sunburn and contribute to skin cancer risk. Others absorb the UVA part of the spectrum. Recent research suggests the longer UVA wavelengths not only penetrate to deeper layers of the skin but contribute to skin cancer through compromising immune response to DNA damage.

For that reason, sunscreen labelled “broad spectrum” is recommended as it offers the best protection.

Broad action sunscreen is recommended.
from shutterstock.com

UV “reflectors” are mostly made up of metals, like zinc oxide and titanium dioxide, that scatter UV radiation. The tiny flakes of metal act like mirrors to reflect the UV away from the skin.

There is normally more than one and often up to six or more active ingredients in most sunscreens.

The emulsion – the lotion, milk, cream, oil, foam or gel – is what carries the active ingredient. It is usually made up of some combination of oil and water, plus other goodies. These are important as they preserve the product so it lasts on the shelf or in your cupboard. They also help with water resistance, influence how the sunscreen feels and smells, and how well it binds to the skin.

What does SPF mean and how is it measured?

Sunscreen provides a screen, not a block. Think of a fly-screen door: air gets though but flies don’t. In the same way, the sun lotion or potion of your choice allows some small amount of UV radiation onto your skin.

A sunscreen with SPF 30 isn’t much lower in protection than SPF 50.
Mike Mozart/Flickr, CC BY

SPF stands for sun protection factor. It’s the measure of how much UV gets through the screen. The higher the number, the less UV passes through.

An SPF of 30 allows one-thirtieth or 3.3% of UV to reach your skin. This means it filters 96.7% of UV. With an SPF of 50, 98% is filtered and one-fiftieth or 2% gets through.

So while the difference between SPF 30 and SPF 50 sounds like a lot – it is a pretty modest (1.3%) – difference in protection.

Put another way, if your unprotected skin would take ten minutes to show signs of burning, then properly applying SPF 30 sunscreen would slow the rate of burning to the point where it would take 30 times longer, or 300 minutes in total. SPF 15 would take 150 minutes, while SPF 50, 500 minutes.

But this is perfect world stuff. If you extend your stay in the sun for 500 minutes (over eight hours!) only relying on sunscreen, you will very likely still burn!


Read more: What happens to your skin when you get sunburnt?


When and how do I put it on?

At a microscopic level, the skin is a series of peaks and troughs. Layering on sunscreen around 20 minutes before going into the sun allows the product to flow into the troughs and bind properly to the skin.

The skin is a series of peaks and troughs.
from shutterstock.com

Many sunscreens recommend reapplying every two hours. But another way to look at it is like painting a wall of your house. The first coat gets a reasonable coverage, but a reapplication 20-30 minutes after being in the sun – after the first coat has “dried” – gets you much more reliable coverage. And this will cover the bits you may have missed, or covered too thinly, on first pass.

Also, use it generously. Most people use too little (between a quarter and three-quarters) of the amount of sunscreen necessary to achieve the sun protection claimed on the label. A teaspoon per limb is a good rule of thumb. Add another teaspoon for your face, front and back. This comes to seven teaspoons (35ml) in all if you are at the beach in board shorts or a bikini.

You need to apply around seven teaspoons of sunscreen in all if you’re at the beach in a bikini.
Photo by rawpixel.com on Unsplash, CC BY

Layer it on and spread it around. Reapply every two hours or more often if you are active (sweating, towelling off, skin making physical contact with anything that might rub it off), even if the bottle claims four-hour water resistance. And a good idea is to check if the lotion hasn’t passed its use-by date.

Use other things to protect your skin too. Hats, shade, clothing and even staying indoors at the highest UV periods. The closer to solar noon, usually between midday and 12.30pm, the higher the UV.


Read more: Will I damage my eyes if I don’t wear sunglasses?


The World Health Organisation recommends protecting skin from the sun when the UV Index is 3 or above. The Bureau of Meteorology reports on the UV Index around Australia and the SunSmart App allows you to get live readings on your smartphone.

How long can I stay in the sun with sunscreen on?

It’s wise to stay in the sun no longer than is necessary to do your planned activity. Staying out longer just because you have the sunscreen “suit of armour” (which it is not) is a bad idea.

Even following all the best advice, the normal daily activity – wiping water from your eyes, scratching an itch, cuddling the kids, brushing against a tree or your best buddy – will remove sunscreen and diminish its performance. And remember it is screening, not blocking the sun.

The ConversationAnd will you still get a tan if you put on sunscreen properly? Well, no. If sunscreen is properly applied to do its job of reducing UV radiation exposure, it prevents the biological process of tanning.

Terry Slevin, Adjunct Professor, School of Psychology, Curtin University; Education and Research Director, Cancer Council WA; Chair, Occupational and Environmental Cancer Committee, Cancer Council Australia

This article was originally published on The Conversation. Read the original article.

Why getting enough sleep should be on your list of New Year’s resolutions



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Getting enough sleep can help our memory, waistline and our performance at work.
David Mao

Amy Reynolds, CQUniversity Australia; Doug McEvoy, Flinders University; Robert Adams, University of Adelaide, and Sally Ferguson, CQUniversity Australia

If you need an alarm to get up in the morning, you’re probably not getting enough sleep.

More than 40% of Australians get too little sleep to feel rested and able to function at their best. The average amount for an adult is around seven hours, while only 8% are lucky enough to get more than nine hours. Some 12% of Australians get less than 5.5 hours, and three-quarters of those struggle to get through their day.

These holidays, ditch the alarm clock and make getting enough sleep one of your New Year’s resolutions. Your memory, waistline and even your employer may thank you for it.

Why getting enough sleep should be a priority

Our brains use sleep time to sort through our experiences. We “clean up” and get rid of information connections we don’t need from the day just gone. Without adequate sleep, we may not be making enough space for new learning and memories.


Read more: Why our brain needs sleep and what happens if we don’t get it


Getting enough sleep also ensures we are safe to drive on the roads and less likely to make costly mistakes at work and home. Being awake for longer than 17 hours impairs your ability to think clearly as much as having a blood alcohol concentration above 0.05. After 24 hours awake, your ability to perform cognitive tasks is as poor as if you had a blood alcohol concentration of 0.10.

Last year’s Australian sleep survey found 29% of Australian workers reported making errors at work in the previous three months specifically because they hadn’t got enough sleep. One in five respondents reported having nodded off while driving.

Getting enough sleep may also be helpful for managing our food intake. When people are only allowed to sleep for short periods of time, they are more likely to choose to snack food, particularly sweet snacks.

It’s natural to reach for sweet snacks when we don’t get enough sleep.
Sarah Swinton

The body’s response to eating food changes when sleep is restricted; as little as one week of restricted sleep is associated with glucose (sugar) levels approaching pre-diabetic levels.

The benefit is not limited to individual well-being. Australian workers who feel they get inadequate sleep are more likely to take a sick day than those who feel they get enough.

So, how much sleep do we need?

The American Sleep Foundation recommends adults aged between 18 and 64 get between seven and nine hours of sleep a night, while older adults should aim for seven to eight hours.


Read more – Explainer: how much sleep do we need?


Your ideal sleep duration will be unique to you and fall somewhere within the recommended range. To find out how much sleep you need, try a week-long experiment and modified sleep regime. Think of it as your holiday homework:

  • Cut back on how much you are doing during the week, particularly in the evening, to give yourself time to wind down

  • Put away the technology. A tech ban in the bedroom might be the best start

  • Create a dark sleeping space

  • Get rid of the alarm clock so your body has the chance to tell you how much sleep you need

  • Keep a week-long diary of your sleep times and daytime energy levels to get a feel for how much sleep feels good the next day.

Over a week, see how much sleep you actually need to feel fresh.
Warren Wong

You might find you need to sleep longer than usual for the first couple of nights. But remember, this is an exercise to work out how sleep can help you feel good rather than a test to see how much sleep you “must” or “can” get as this pressure may not help with sleeping well.

You might feel a little groggy the next morning which is normal, but you should wake up – and get up – when you feel well-rested.


Further reading – Health Check: how can I make it easier to wake up in the morning


By seeing where you sit on the sleep spectrum, you can work out the bed and wake times that best suit your needs.

How to get more sleep

Here are some starting points to make sleep more of a priority.

1) Reduce your exposure to bright lights in the evening

Allowing your body to naturally respond to the light and dark cycle each day can lead to earlier bed times.

Ditching distractors that delay our bedtimes can help shift the increase in the hormone melatonin, which makes us sleepy, to earlier in the evening.

As little as one weekend of camping away from electrical lighting, including blue light in our devices, can help us become early risers.

Camping is a good way to reset the body clock.
Patrick Hendry

If there’s no time for camping this Christmas, try a “camp at home” approach by reducing your light exposure throughout the house at night; dim and fewer lights in the evening is ideal.

2) Establish a routine

While some find falling asleep a breeze, this can be a slow process for many. Consistent activities – such as brushing your teeth, reading a book – at a regular time each evening can help your body recognise and prepare for heading to bed.


Read more – Health Check: how to soothe yourself to sleep


Make sure this time is in addition to the time you set aside for sleep, so you have enough time to wind down before bed.

This routine extends to consistent wake times. A regular bed and wake time schedule should be complimentary.

3) Talk to your doctor about your sleep

If you’re told you snore, or you never feel refreshed even after what seems to be a long sleep, talk to your GP about whether you might have an underlying disorder that makes getting enough sleep harder.

According to last year’s national sleep survey, 8% of Australians have diagnosed sleep apnoea, 18% have restless leg syndrome and 20% have insomnia. Getting help for these conditions will impact your physical and mental health.

The ConversationWhile time spent sleeping may feel akin to “doing nothing” for your health, the benefits of regular, refreshing sleep for your brain and body mean that it should be on your New Year’s resolution list right next to healthy eating and exercise.

Amy Reynolds, Lecturer in Psychology, CQUniversity Australia; Doug McEvoy, Chief investigator, National Centre for Sleep Health Services Research, Flinders University; Robert Adams, Professor of Medicine, University of Adelaide, and Sally Ferguson, Research professor, CQUniversity Australia

This article was originally published on The Conversation. Read the original article.

Strength training can have unique health benefits, and it doesn’t have to happen in a gym



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You don’t need to hit the gym to reduce your chance of early death.
from http://www.shutterstock.com

Emmanuel Stamatakis, University of Sydney

Most of us probably know exercising is associated with a smaller risk of premature death, but a new study has found that doesn’t have to happen in a CrossFit box, a ninja warrior studio, or even a gym. Body weight-bearing exercises such as sit-ups and push-ups staved off death just as much as other forms of weight-bearing exercise.

Our study recruited just over 80,000 adults over 30 years living in England and Scotland between 1994 and 2008, who were followed up for an average of nine years. At the end of the followup period, we calculated their risk of death according to their strength-promoting exercise and how much they did.

What we found

Those who reported participation in any strength-promoting exercise (including gym workouts) averaged about 60 minutes a week and those who reported any own body weight exercises averaged 50 minutes a week. Participation in either gym workouts or own body weight exercises reduced the risk of early death by about 20%. Cancer-related deaths also decreased by 24-27%, but there was little evidence more was better.


Read more: Do you even lift? Why lifting weights is more important for your health than you think


We also compared the risk of those who met the recommendation of two sessions of strength-promoting exercise per week, with those who met the recommendation of 150 minutes of aerobic physical activity such as walking (or 75 minutes more intense, such as running) per week.

Compared to being inactive, meeting either guideline was associated with a 16-18% reduction in risk of early death.

But the results on cancer death risk told us a very different story. Those who met only the strength-promoting guideline by doing body weight exercises had a 31% lower risk of death from cancer. Those who met only the aerobic exercise guideline had no reduction in risk of cancer death.

On the other hand, reducing the risk of death from heart disease was only associated with aerobic physical activity (21% reduction).

Gyms can be daunting for beginners.
from http://www.shutterstock.com

Interpreting the results

Given this research is observational, there’s always a chance the relationship between exercise and early death could be due to other causes. Perhaps the people who exercised more were also just generally healthier in other ways.

To reduce the possibility of alternative explanations, we adjusted our results for age, sex, health status, obesity, other lifestyle behaviours (smoking, alcohol, diet), education level, mental health, and participation in other physical activity such as domestic activities, walking and aerobic exercise.

People with chronic diseases are less likely to exercise, and more likely to die early. Therefore we excluded from the results all participants who had heart disease or cancer, as well as those who died in the first two years of the followup (because their death was most likely caused by something they had prior to the study commencing).

Other studies have examined the relationship between strength promoting exercise and early death. An American study found lifting weights or doing callisthenics was associated with a 31% decrease in risk of death from any cause, which is consistent with our results. But contrary to our results, the same study found no association with cancer death risk.

Another study among cancer survivors showed lifting weights, but not aerobic activities, was associated with a 33% lower risk of death from any cause.


Read more: How we can change our body shape with exercise


What it all means

Our study suggests exercise that promotes muscular strength has unique health benefits and is at least as important for health as walking, cycling, and other aerobic activities.

We shouldn’t forget the most important principle for choosing an activity is being able to incorporate it into your routine and stick to it long term. The simplicity of body weight exercises makes them a very attractive option: they are inexpensive and require little skill and no equipment. Plus we now know they yield comparable benefits to similar gym-based activities. This is important given gyms can be daunting or unaffordable for many people.

So in addition to doing enough moderate to vigorous intensity aerobic activity, good old fashioned push-ups or chin-ups at home, in the park, in the yard, or even in the office could be an excellent option. For most people two to three sessions a week would be sufficient for general health.

The ConversationThe American College of Sports Medicine recommends 2-4 sets of 8-15 repetitions of each strength promoting exercise with 2-3 minutes rest between sets. As with any physical activity, the most important principle here is a little is better than nothing, and gradually build up from little to enough.

Emmanuel Stamatakis, Associate Professor; Physical Activity, Lifestyle, and Health Behaviours, University of Sydney

This article was originally published on The Conversation. Read the original article.

Why our brain needs sleep, and what happens if we don’t get enough of it


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Sleep is the time for our brain to reboot.
Hernan Sanchez/Unsplash, CC BY-SA

Leonie Kirszenblat, The University of Queensland

Many of us have experienced the effects of sleep deprivation: feeling tired and cranky, or finding it hard to concentrate. Sleep is more important for our brains than you may realise.

Although it may appear you’re “switching off” when you fall asleep, the brain is far from inactive. What we know from studying patterns of brain electrical activity is that while you sleep, your brain cycles through two main types of patterns: rapid eye movement (REM) sleep and slow-wave sleep.

Slow-wave sleep, which occurs more at the beginning of the night, is characterised by slow rhythms of electrical activity across large numbers of brain cells (occurring one to four times per second). As the night progresses, we have more and more REM sleep. During REM sleep we often have vivid dreams, and our brains show similar patterns of activity to when we are awake.


Read more – Health Check: three reasons why sleep is important for your health


What are our brains doing while we sleep?

Sleep serves many different functions. One of these is to help us remember experiences we had during the day. REM sleep is thought to be important for emotional memories (for example, memories involving fear) or procedural memory (such as how to ride a bike). On the other hand, slow-wave sleep is thought to reflect the storing of so-called “declarative” memories that are the conscious record of your experiences and what you know (for example, what you had for breakfast).

We also know experiences are “replayed” in the brain during sleep – the memories of these experiences are like segments from a movie that can be rewound and played forward again. Replay occurs in neurons in the hippocampus – a brain region important for memory – and has been best studied in rats learning to navigate a maze. After a navigation exercise, when the rat is resting, its brain replays the path it took through the maze. Replay helps to strengthen the connections between brain cells, and is therefore thought to be important for consolidating memories.

While we’re asleep our brain does a tidy-up, only keeping what it needs.
Sashank Saye/Unsplash

But is it that important for you to remember what you had for breakfast? Probably not – that’s why the brain needs to be selective about what it remembers. Sleep allows the brain to sift through memories, forgetting certain things so as to remember what’s important. One way it may do this is by “pruning away” or “scaling down” unwanted connections in the brain.

A leading theory of sleep function – the “synaptic homeostasis hypothesis” – suggests that during sleep there is a widespread weakening of connections (known as “synapses”) throughout the brain.

This is thought to counterbalance the overall strengthening of connections that occurs during learning when we are awake. By pruning away excess connections, sleep effectively “cleans the slate” so we can learn again the next day. Interfering with this scaling down process can, in some cases, lead to more intense (and perhaps unwanted) memories.

The importance of sleep for keeping our brains optimally active may be reflected in our changing sleep patterns as we age. Babies and children sleep much more than adults, probably because their developing brains are learning much more, and being exposed to new situations.

Later in life, sleep declines and becomes more fragmented. This may reflect either a reduced need for sleep (as we are learning less) or a breakdown in sleep processes as we age.


Read more – Children and sleep: How much do they really need?


Sleep is also needed to do a bit of brain “housekeeping”. A recent study in mice found sleep cleanses the brain of toxins that accumulate during waking hours, some of which are linked to neurodegenerative diseases. During sleep, the space between brain cells increases, allowing toxic proteins to be flushed out. It’s possible that by removing these toxins from the brain, sleep may stave off neurodegenerative diseases like Alzheimer’s.

What happens if we have a bad night’s sleep?

Getting enough sleep is important for attention and learning during our waking hours. When we are sleep deprived, we can’t focus on large amounts of information or sustain our attention for long periods. Our reaction times are slowed. We are also less likely to be creative or discover hidden rules when trying to solve a problem.

When you haven’t had enough sleep, your brain may force itself to shut down for a few seconds when you’re awake. During this “micro-sleep” you may become unconscious for a few seconds without knowing it. Drowsiness while driving is a leading cause of motor vehicle accidents, with sleep deprivation affecting the brain just as much as alcohol. Sleep deprivation can also lead to fatal accidents in the workplace – a major issue in shift workers.


Read more – Explainer: how much sleep do we need?


The beneficial effects of sleep on attention and concentration are particularly important for children, who often become hyperactive and disruptive in class when they don’t have enough sleep. One study found getting just one hour less sleep per night over several nights can adversely affect a child’s behaviour in class.

What are the long-term effects?

The longer-term effects of sleep deprivation are more difficult to study in humans for ethical reasons, but chronic sleep disturbances have been linked to brain disorders such as schizophrenia, autism and Alzheimer’s. We don’t know if sleep disturbances are a cause or symptom of these disorders.

The ConversationOverall, the evidence suggests having healthy sleep patterns is key to having a healthy and well-functioning brain.

Leonie Kirszenblat, Postdoctoral research fellow, The University of Queensland

This article was originally published on The Conversation. Read the original article.