Last week, the Therapeutic Goods Administration (TGA) released its safety review of seven active ingredients commonly used in sunscreens.

It found five were low-risk and appropriate for use in sunscreens at their current concentrations.

However, the TGA recommended tighter restrictions on two ingredients – homosalate and oxybenzone – to reduce how much can be used in a product. This is based on uncertainty about their potential effects on the endocrine system, which creates and releases hormones.

This news, together with recent reports some products may have inflated their claims of SPF coverage, might make Australians worried about whether their sunscreen products are working – and safe.

But it’s not time to abandon sunscreens. In Australia, all sunscreens must pass a strict approval process before going on the market. The TGA tests the safety and efficacy of all ingredients, and this recent review is part of the TGA’s continuing commitment to safety.

The greatest threat sunscreen poses to Australians’ health is not using it.

Australia has the highest incidence of melanoma and non-melanoma skin cancer worldwide, and approximately 95% of melanoma cases in Australia are linked to ultraviolet (UV) exposure.

Still, it’s understandable people want to know what’s in their products, and any changes that might affect them. So let’s take a closer look at the safety review and what it found.

What are the active ingredients in sunscreen?

There are two main types of sunscreen: physical and chemical. This is based on the different active ingredients they use.

An active ingredient is a chemical component in a product that has an effect on the body – basically, what makes the product “work”.

In sunscreens, this is the compound that absorbs UV rays from the Sun. The other ingredients – for example, those that give the sunscreen its smell or help the skin absorb it – are “inactive”.

Physical sunscreens typically use minerals, such as titanium dioxide and zinc oxide, that can absorb the Sun’s rays but also reflect some of them.

Chemical sunscreens use a variety of chemical ingredients to absorb or scatter UV light, both long wave (UVA) or short wave (UVB).

The seven active ingredients in this review are in chemical sunscreens.

Why did the TGA do the review?

Our current limits for the concentrations of these chemicals in sunscreen are generally consistent with other regulatory agencies, such as the European Union and the US Food and Drug Administration.

However, safety is an evolving subject. The TGA periodically reexamines the safety of all therapeutic goods.

Last year, the TGA revised its method of estimating sunscreen exposure to more closely model how skin is exposed to sunscreens over time.

This model considers how much sunscreen someone typically applies, how much skin they cover (whole body versus face and hands, or just face) and how it’s absorbed through the skin.

Given this new model – along with changes in the EU and US approaches to sunscreen regulation – the TGA selected seven common sunscreen ingredients to investigate in depth.

Determining what’s safe

When evaluating whether chemicals are safe for human use, testing will often consider studies in animals – especially when there is no or limited data on humans. These animal tests are done by the manufacturers, not the TGA.

To take into account any unforeseen sensitivity humans may have to these chemicals, a “margin of safety” is built in. This is typically a concentration 50–100 times lower than the dose at which no negative effect was seen in animals.

The sunscreen review used a margin of safety 100 times lower than this dose as the safety threshold.

For most of the seven investigated sunscreen chemicals, the TGA found the margin of safety was above 100.

This means they’re considered safe and low-risk for long-term use.

However, two ingredients, homosalate and oxybenzone, were found to be below 100. This was based on the highest estimated sunscreen exposure, applied to the body at the maximum permitted concentration: 15% for homosalate, 10% for oxybenzone.

At lower concentrations, other uses – such as just the hands and face – could be considered low-risk for both ingredients.

What are the health concerns?

Homosalate and oxybenzone have low acute oral toxicity – meaning you would need to swallow a lot of it to experience toxic effects, nearly half a kilogram of these chemicals – and don’t cause irritation to eyes or skin.

There is inconclusive evidence about oxybenzone potentially causing cancer in rats and mice – but only at concentrations to which humans will never be exposed via sunscreens.

The key issue is whether the two ingredients affect the endocrine system.

While effects have been seen at high concentrations in animal studies, it is not clear whether these translate to humans exposed to sunscreen levels.

No effect has been seen in clinical studies on fertility, hormones, weight gain and, in pregnant women, fetal development.

The TGA is being very cautious here, using a very wide margin of safety under worst-case scenarios.

What are the recommendations?

The TGA recommends the allowed concentration of homosalate and oxybenzone be reduced.

But exactly how much it will be lowered is complicated, depending on whether the product is intended for adults or children, specifically for face, or the whole body, and so on.

However, some sunscreens would need to be reformulated or warning labels placed on particular formulations. The exact changes will be decided after public consultation. Submissions close on August 12.

What about benzophenone?

There is also some evidence benzophenone – a chemical produced when sunscreen that contains octocrylene degrades – may cause cancer at high concentrations.

This is based on studies in which mice and rats were fed benzophenone well above the concentration in sunscreens.

Octocrylene degrades slowly over time to benzophenone. Heat makes it degrade faster, especially at temperatures above 40°C.

The TGA has recommended restricting benzophenone to 0.0383% in sunscreens to ensure it remains safe during the product’s shelf life.

The Cancer Council advises storing sunscreens below 30°C.

The bottom line

The proposed restrictions are very conservative, based on worst-case scenarios.

But even in worst-case scenarios, the margin of safety for these ingredients is still below the level at which any negative effect was seen in animals.

The threat of cancer from sun exposure is far more serious than any potential negative effect from sunscreens.

If you do wish to avoid these chemicals before new limits are imposed, several sunscreens are available that provide high levels of protection with little or no homosalate and oxybenzone. For more information, consult product labels.

Ian Musgrave, Senior Lecturer in Pharmacology, University of Adelaide

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

We’ve all been there. The pounding headache, relentless nausea, and the kind of tired no amount of coffee can fix. Hangovers are a reminder that last night’s fun comes at a cost.

These days, hangovers aren’t just something to complain about over a greasy breakfast – they’re big business. The global market for hangover cures is now valued at US$2.29 billion (A$3.53 billion) and projected to reach US$6.71 billion (A$10.33 billion) by 2032.

These products – ranging from capsules to drinks to patches – appear to be popular. Nearly 70% of drinkers say they would buy an effective hangover remedy. But any scientific evidence they work is thin.

First, what causes hangovers?

Despite years of research, the exact cause of a hangover is still unclear. But we know several biological processes contribute to that hungover feeling.

1. Your immune system is in overdrive

When you drink, your body treats alcohol like a threat. It breaks alcohol down into acetaldehyde, a toxic byproduct that triggers an immune response, releasing inflammatory chemicals called cytokines.

These chemicals are the same ones your body uses to fight infections, which is why a hangover can feel eerily similar to being sick.

2. You’re dehydrated

Alcohol blocks vasopressin, a hormone that helps the body retain water. Without it, you make more frequent trips to the bathroom and lose more fluid than you take in, leading to thirst, dry mouth, and the classic hangover headache.

3. Your sleep takes a hit

Although alcohol might help you fall asleep faster, it disrupts your natural sleep pattern. You get more deep sleep early on, but less rapid eye movement (REM) and light sleep stages.

As the alcohol wears off, your brain rebounds with more REM sleep and frequent wake ups, leaving you groggy and cognitively impaired the next day.

4. Your brain is recalibrating

Alcohol disrupts several brain chemicals. It boosts gamma-aminobutyric acid, a calming neurotransmitter, and suppresses glutamate, which normally keeps you stimulated and alert. That’s part of why drinking feels relaxing. But as your body tries to rebalance, you may be left feeling anxious or irritable.

What’s in hangover ‘remedies’?

Modern hangover remedies have evolved well beyond the “hair of the dog”. You’ve got liver-protecting capsules, electrolyte-packed drinks, vitamin patches for while you party, and strips that dissolve on your tongue – all with the goal of accelerating recovery.

A 2025 analysis which looked at hangover products marketed in Australia found B vitamins and sodium were the most common ingredients, appearing in nearly half of all products reviewed.

B vitamins are often included based on the idea alcohol depletes them, while sodium is thought to support rehydration. However, there’s little solid evidence that either significantly improves hangover symptoms in otherwise healthy people.

Natural ingredients such as ginger and dihydromyricetin, a compound extracted from the Japanese raisin tree, were also popular, featuring in more than one-quarter and one-third of products respectively.

Ginger is widely used to treat nausea and vomiting, and there’s some evidence to support its effectiveness for gastrointestinal symptoms. However, this is not specific to hangovers.

Dihydromyricetin has been marketed as a revolutionary hangover fighter, with claims it helps the liver process alcohol more efficiently. Yet, when tested under controlled conditions, it failed to reduce hangover severity more than a placebo.

Other popular ingredients show similarly underwhelming results. The amino acid L-cysteine has shown some benefits in one study, but the sample was too small to draw firm conclusions.

Another product often marketed as a hangover remedy is Korean pear juice. If consumed before drinking, it may help the body break down alcohol more efficiently. A 2013 study found it slightly lowered blood alcohol levels and improved focus. However the effects were small, and it offered little benefit once a hangover had already set in.

Another natural remedy that has shown some promise is red ginseng. One study found participants who drank red ginseng extract after alcohol were less thirsty, fatigued, had fewer stomach aches, and even had improved memory compared to people who drank just plain water.

Mouse trials of ginseng have also shown consistent benefits across symptoms and biological markers of alcohol-related stress.

How about IV drips and vitamin patches?

Not all remedies come in pill or plant form. IV drips, often marketed as wellness boosters for energy, immunity, and even glowing skin, are now offered at clinics and “drip bars” for hangovers too. But unless you’re severely dehydrated, there’s little evidence these pricey infusions work any better than water, food and rest.

Vitamin patches are also trending, claiming to deliver nutrients through the skin while bypassing digestion. But again, studies don’t necessarily support this. Most vitamins are better absorbed through food or oral supplements.

There’s no magic cure for a hangover

As the hangover remedy market continues to grow, science hasn’t kept pace with marketing claims. However, these science-backed strategies may help:

• pacing yourself and having no more than one standard drink an hour gives your liver time to keep up, so you’re less likely to feel too drunk or hungover the next day
• stay hydrated by alternating alcoholic drinks with water
• eating before drinking slows alcohol absorption and can help reduce stomach irritation
• get plenty of sleep after a big night out, as your body does most of its recovery while you rest. Even a short nap the next day can help you feel better.

Practising moderation can be difficult in the moment. But it’s likely to be your best bet to avoid waking up feeling rough the next day.

Blair Aitken, Postdoctoral Research Fellow in Psychopharmacology, Swinburne University of Technology and Rebecca Rothman, PhD Candidate in Clinical Psychology, School of Health Sciences, Swinburne University of Technology

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