Round Lab sun stick: what it is and how to use it

What is in the Round Lab sun stick?

The listed sunscreen filters are homosalate 9.5%, octocrylene 5%, octisalate 4.5% and avobenzone 3%. The formula also includes birch sap, glycerin, hyaluronic acid and allantoin. Round Lab describes a lightweight balm with a clear, non greasy finish. The balm comes in a 19 g stick, which is a small container for such a long product name.1

What does SPF 50 protect against?

SPF mainly describes protection against UVB, the ultraviolet radiation responsible for sunburn. Broad spectrum protection also covers UVA, which contributes to skin ageing and skin cancer. Chemical sunscreen filters absorb ultraviolet radiation. The sunscreen filters provide sun protection; the moisturizing ingredients are not a substitute for them.345

SPF testing uses a defined amount of sunscreen: 2 milligrams per square centimetre of skin. Applying less can leave you with less protection than the advertised rating. SPF 50 does not mean you can stay outside 50 times longer, and no sunscreen blocks every ultraviolet ray.234

How do you apply the sun stick?

Use Round Lab's handling directions alongside these general sunscreen application steps.

1. 1Start with clean, dry skin. Apply sunscreen at the end of your skincare routine, before going outdoors.
2. 2Raise the stick by about 5 mm. Round Lab warns that twisting it up too far can cause breakage or separation.
3. 3Apply four passes back and forth over each area you want to protect. This is general stick sunscreen guidance, rather than a Round Lab specific pass count.
4. 4Rub the sunscreen in afterwards to create an even layer. Keep it out of your eyes and mouth.
5. 5Cover exposed areas thoroughly, including the ears, nose, back of the neck, hands, hairline and tops of the feet. Use an SPF lip balm on your lips.
6. 6Apply 15 to 20 minutes before sun exposure. Follow any additional directions on your own pack.

Stick sunscreens are useful for smaller areas such as the backs of the hands and beneath the eyes, while keeping the product out of the eyes themselves. A targeted touch up only protects the area you cover: it does not replace applying sunscreen to the rest of your exposed skin.23

How often should you reapply it?

Reapply sunscreen at least every two hours while outdoors, and immediately after swimming or sweating. Apply sunscreen daily when the forecast ultraviolet index reaches 3 or higher. Your exposure matters beyond sunbathing: outdoor work, hobbies and sport also require protection.256

Do not assume the stick is water resistant. For swimming or sweaty activity, check the packaging for a water resistance claim and a stated duration. Water resistant sunscreens are labelled for 40 or 80 minutes of swimming or sweating; neither means waterproof. Reapplication is still necessary.3

Who should choose it, and who should be careful?

Choose the stick if you prefer a balm for portable reapplication. Round Lab markets it for all skin types, including sensitive skin, but its unscented description should not be read as an assurance of tolerance. The ingredient list includes pine leaf oil and chamomile flower oil.1

Do not apply the stick to damaged or broken skin. Stop using it and ask a doctor if a rash occurs. Rinse with water if it gets into your eyes. Keep it away from children, and seek medical help or contact a Poison Control Center if swallowed.1

For babies younger than six months, prioritize keeping them out of direct sun and using protective clothing. Ask a doctor before applying sunscreen at that age. For older children, follow the product's Drug Facts directions rather than treating the stick format as permission to skip the label.3

What is Round Lab sun serum?

Birch Juice Moisturizing Sun Serum is a separate broad spectrum SPF 50 sunscreen with a weightless serum texture. Round Lab sells both a Birch Moisturizing Serum and a Birch Juice Moisturizing Sun Serum, so the word "sun" is doing more work than the rest of the name.7

The stick and sun serum are both listed at $37.00, so the format choice does not need a financial subplot.7

What else do you need for sun protection?

Combine sunscreen with shade, clothing that covers exposed skin, a hat that shades the face and neck, and sunglasses with ultraviolet protection. A baseball cap leaves the ears and neck exposed. Closely woven clothing provides more protection, and a UPF rating of 30 or higher indicates good protection. Dry clothes are preferable after swimming because wet fabric is often less protective.56

How should you store the stick?

Keep sunscreen in a cool, accessible place, protected from excessive heat and direct sunlight. Check the expiry date before using it. Discard expired sunscreen; if there is no expiry date, discard it three years after purchase. If you do not know how old it is, replace it.36