Australians have used commercial creams, lotions or gels to manage our skin’s sun exposure for nearly a century.

But why we do it, the preparations themselves, and whether they work, has changed over time.

In this short history of sunscreen in Australia, we look at how we’ve slathered, slopped and spritzed our skin for sometimes surprising reasons.

At first, suncreams helped you ‘tan with ease’

Sunscreens have been available in Australia since the 30s. Chemist Milton Blake made one of the first.

He used a kerosene heater to cook batches of “sunburn vanishing cream”, scented with French perfume.

His backyard business became H.A. Milton (Hamilton) Laboratories, which still makes sunscreens today.

Hamilton’s first cream claimed you could “
Sunbathe in Comfort and TAN with ease”. According to modern standards, it would have had an SPF (or sun protection factor) of 2.

The mirage of ‘safe tanning’

A tan was considered a “modern complexion” and for most of the 20th century, you might put something on your skin to help gain one. That’s when “safe tanning” (without burning) was thought possible.

Sunburn was known to be caused by the UVB component of ultraviolet (UV) light. UVA, however, was thought not to be involved in burning; it was just thought to darken the skin pigment melanin. So, medical authorities advised that by using a sunscreen that filtered out UVB, you could “safely tan” without burning.

But that was wrong.

From the 70s, medical research suggested UVA penetrated damagingly deep into the skin, causing ageing effects such as sunspots and wrinkles. And both UVA and UVB could cause skin cancer.

Sunscreens from the 80s sought to be “broad spectrum” – they filtered both UVB and UVA.

Researchers consequently recommended sunscreens for all skin tones, including for preventing sun damage in people with dark skin.

Delaying burning … or encouraging it?

Up to the 80s, sun preparations ranged from something that claimed to delay burning, to preparations that actively encouraged it to get that desirable tan – think, baby oil or coconut oil. Sun-worshippers even raided the kitchen cabinet, slicking olive oil on their skin.

One manufacturer’s “sun lotion” might effectively filter UVB; another’s merely basted you like a roast chicken.

Since labelling laws before the 80s didn’t require manufacturers to list the ingredients, it was often hard for consumers to tell which was which.

At last, SPF arrives to guide consumers

In the 70s, two Queensland researchers, Gordon Groves and Don Robertson, developed tests for sunscreens – sometimes experimenting on students or colleagues. They printed their ranking in the newspaper, which the public could use to choose a product.

An Australian sunscreen manufacturer then asked the federal health department to regulate the industry. The company wanted standard definitions to market their products, backed up by consistent lab testing methods.

In 1986, after years of consultation with manufacturers, researchers and consumers, Australian Standard AS2604 gave a specified a testing method, based on the Queensland researchers’ work. We also had a way of expressing how well sunscreens worked – the sun protection factor or SPF.

This is the ratio of how long it takes a fair-skinned person to burn using the product compared with how long it takes to burn without it. So a cream that protects the skin sufficiently so it takes 40 minutes to burn instead of 20 minutes has an SPF of 2.

Manufacturers liked SPF because businesses that invested in clever chemistry could distinguish themselves in marketing. Consumers liked SPF because it was easy to understand – the higher the number, the better the protection.

Australians, encouraged from 1981 by the Slip! Slop! Slap! nationwide skin cancer campaign, could now “slop” on a sunscreen knowing the degree of protection it offered.

How about skin cancer?

It wasn’t until 1999 that research proved that using sunscreen prevents skin cancer. Again, we have Queensland to thank, specifically the residents of Nambour. They took part in a trial for nearly five years, carried out by a research team led by Adele Green of the Queensland Institute of Medical Research. Using sunscreen daily over that time reduced rates of squamous cell carcinoma (a common form of skin cancer) by about 60%.

Follow-up studies in 2011 and 2013 showed regular sunscreen use almost halved the rate of melanoma and slowed skin ageing. But there was no impact on rates of basal cell carcinoma, another common skin cancer.

By then, researchers had shown sunscreen stopped sunburn, and stopping sunburn would prevent at least some types of skin cancer.

What’s in sunscreen today?

An effective sunscreen uses one or more active ingredients in a cream, lotion or gel. The active ingredient either works:

• “chemically” by absorbing UV and converting it to heat. Examples include PABA (para-aminobenzoic acid) and benzyl salicylate, or

• “physically” by blocking the UV, such as zinc oxide or titanium dioxide.

Physical blockers at first had limited cosmetic appeal because they were opaque pastes. (Think cricketers with zinc smeared on their noses.)

With microfine particle technology from the 90s, sunscreen manufacturers could then use a combination of chemical absorbers and physical blockers to achieve high degrees of sun protection in a cosmetically acceptable formulation.

Where now?

Australians have embraced sunscreen, but they still don’t apply enough or reapply often enough.

Although some people are concerned sunscreen will block the skin’s ability to make vitamin D this is unlikely. That’s because even SPF50 sunscreen doesn’t filter out all UVB.

There’s also concern about the active ingredients in sunscreen getting into the environment and whether their absorption by our bodies is a problem.

Sunscreens have evolved from something that at best offered mild protection to effective, easy-to-use products that stave off the harmful effects of UV. They’ve evolved from something only people with fair skin used to a product for anyone.

Remember, slopping on sunscreen is just one part of sun protection. Don’t forget to also slip (protective clothing), slap (hat), seek (shade) and slide (sunglasses).

Laura Dawes, Research Fellow in Medico-Legal History, Australian National University

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

Back pain is common. One in thirteen people have it right now and worldwide a staggering 619 million people will have it this year.

Chronic pain, of which back pain is the most common, is the world’s most disabling health problem. Its economic impact dwarfs other health conditions.

If you get back pain, how long will it take to go away? We scoured the scientific literature to find out. We found data on almost 20,000 people, from 95 different studies and split them into three groups:

• acute – those with back pain that started less than six weeks ago
• subacute – where it started between six and 12 weeks ago
• chronic – where it started between three months and one year ago.

We found 70%–95% of people with acute back pain were likely to recover within six months. This dropped to 40%–70% for subacute back pain and to 12%–16% for chronic back pain.

Clinical guidelines point to graded return to activity and pain education under the guidance of a health professional as the best ways to promote recovery. Yet these effective interventions are underfunded and hard to access.

More pain doesn’t mean a more serious injury

Most acute back pain episodes are not caused by serious injury or disease.

There are rare exceptions, which is why it’s wise to see your doctor or physio, who can check for signs and symptoms that warrant further investigation. But unless you have been in a significant accident or sustained a large blow, you are unlikely to have caused much damage to your spine.

Even very minor back injuries can be brutally painful. This is, in part, because of how we are made. If you think of your spinal cord as a very precious asset (which it is), worthy of great protection (which it is), a bit like the crown jewels, then what would be the best way to keep it safe? Lots of protection and a highly sensitive alarm system.

The spinal cord is protected by strong bones, thick ligaments, powerful muscles and a highly effective alarm system (your nervous system). This alarm system can trigger pain that is so unpleasant that you cannot possibly think of, let alone do, anything other than seek care or avoid movement.

The messy truth is that when pain persists, the pain system becomes more sensitive, so a widening array of things contribute to pain. This pain system hypersensitivity is a result of neuroplasticity – your nervous system is becoming better at making pain.

Reduce your chance of lasting pain

Whether or not your pain resolves is not determined by the extent of injury to your back. We don’t know all the factors involved, but we do know there are things that you can do to reduce chronic back pain:

• understand how pain really works. This will involve intentionally learning about modern pain science and care. It will be difficult but rewarding. It will help you work out what you can do to change your pain
• reduce your pain system sensitivity. With guidance, patience and persistence, you can learn how to gradually retrain your pain system back towards normal.

How to reduce your pain sensitivity and learn about pain

Learning about “how pain works” provides the most sustainable improvements in chronic back pain. Programs that combine pain education with graded brain and body exercises (gradual increases in movement) can reduce pain system sensitivity and help you return to the life you want.

These programs have been in development for years, but high-quality clinical trials are now emerging and it’s good news: they show most people with chronic back pain improve and many completely recover.

But most clinicians aren’t equipped to deliver these effective programs – good pain education is not taught in most medical and health training degrees. Many patients still receive ineffective and often risky and expensive treatments, or keep seeking temporary pain relief, hoping for a cure.

When health professionals don’t have adequate pain education training, they can deliver bad pain education, which leaves patients feeling like they’ve just been told it’s all in their head.

Community-driven not-for-profit organisations such as Pain Revolution are training health professionals to be good pain educators and raising awareness among the general public about the modern science of pain and the best treatments. Pain Revolution has partnered with dozens of health services and community agencies to train more than 80 local pain educators and supported them to bring greater understanding and improved care to their colleagues and community.

But a broader system-wide approach, with government, industry and philanthropic support, is needed to expand these programs and fund good pain education. To solve the massive problem of chronic back pain, effective interventions need to be part of standard care, not as a last resort after years of increasing pain, suffering and disability.

Sarah Wallwork, Post-doctoral Researcher, University of South Australia and Lorimer Moseley, Professor of Clinical Neurosciences and Foundation Chair in Physiotherapy, University of South Australia

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