When researching this piece I asked a few people if they knew what SPF (Sun Protection Factor) and the star rating meant regarding sunscreens. There was lots of confusion, and very few were aware that the SPF rating does not mean protection against all sun damage – only that from UVB.

It is confusing, as it is a dual system so it does mean spending time looking for the SPF and star rating on the bottle. The sun protection factor, or SPF, is a measure of the amount of ultraviolet B radiation (UVB) protection .SPF’s are rated on a scale of 2 to 50+ based on the level of protection they offer, with 50+ offering the strongest form of UVB protection.

Protection against UVA rays has its own separate rating system. The star rating measures the amount of ultraviolet A radiation (UVA) protection. The UVA star rating ranges from nought to five and indicates the percentage of UVA radiation absorbed by the sunscreen in comparison to UVB. The higher the star rating, the better. Ultraviolet A rays cause skin-ageing and wrinkles. UVB is frequently referred to as the burning ray. Both UVB and UVA rays from the sun can cause skin cancer.

When buying a sunscreen, you should look for the level of UVA protection (denoted by a UVA star rating or the letters UVA inside a circle) and UVB protection (denoted by the SPF). Sunscreens that offer both UVA and UVB protection are sometimes called broad spectrum.

What is the difference between a SPF 10 and a SPF 30?

Imagine that your skin normally begins to burn after 10 minutes in full sun without any protection. A 30 SPF sunscreen would provide 30 times the protection of no sunscreen.

That means 30 times longer before you start to burn, or in this case, 300 minutes. That’s five hours, so one application should do it for the day! In theory yes, but not in practice, as it doesn’t take into account, swimming, perspiration uneven or not enough application of sunscreen.

Lacura Sunscreen from Aldi

Do you need buy expensive sunscreens?

When it comes to protecting your skin in the sun, many people are inclined to turn to the big brands to make sure they’re choosing reliable products.

A recent consumer survey for the Channel 5 Shop Smart: Save Money found that discount sunscreen from Aldi protects much better against UVAs (ultraviolet A-rays) than products from Nivea or Garnier, and for less than half of their price. 

Aldi’s Lacura, which costs €2.79 and Boots Soltan €8.40 both show a five out of five stars rating, meaning they offer the most complete protection. Garnier’s world famous Ambre Solaire, costing €11.50, only has three stars, while Nivea Sun’s €10.60 and Piz Buin’s €21.85  sunscreens show four stars. 

This shows that sunscreens from discount brand Aldi offers a better protection against UVAs than bigger and more expensive brands like Garnier and Nivea, and for less than half the price. 

Some other brands like Boots and Superdrug are no better than Aldi when it comes to UV protection, but cost twice as much. 

UVA Star Rating and UVB SPF

Sunscreen Guide

UVA rays age the skin and causes wrinkles. These rays can pass through clouds and windows.

UVB rays cause burning of the skin which can cause skin cancer.

Broad spectrum sunscreen protects against both UVA and UVB rays.

No sunscreen provides full protection so sunscreen should be used in combination with other sun protection measures – clothing, hats, shade and sunglasses.

It is recommended to apply sunscreen every two hours when outdoors, especially if swimming or sweating a lot. Even if the sunscreen has a SPF of 50, claims to be sweatproof and waterproof, and provides all-day protection, it needs to be reapplied to provide optimal protection.

Apply sunscreen liberally and thoroughly, at least 20-30 minutes before going out so that it has time to absorb into the skin.

 Check the expiry date of the sunscreen, which is usually 12 months once it has been opened.

Use an adequate amount – at least one teaspoon for each arm and leg, front and back of torso. So, that’s a total of seven teaspoons (at least 35 ml of sunscreen) for an adults full body application.