The SPF value on a sunscreen label only means something when the product is applied in a sufficient amount and reapplied on time. In everyday use, protection is mostly lost not in the choice of SPF but in applying too little, applying too late and skipping reapplication.
In short: According to the American Academy of Dermatology (AAD), the face needs at least 1 teaspoon of sunscreen; the AAD describes this as about enough to cover the length of the index and middle fingers. For the exposed areas of the body, most adults need about 1 ounce of product, or a shot glass full. Apply sunscreen about 15 minutes before going outside; while outdoors, reapply at least every two hours, and immediately after swimming, sweating or towel drying.
How much sunscreen should you apply to the face and body?
Apply at least 1 teaspoon of sunscreen to the face and, for adults, about 1 ounce (a shot glass full) to the areas of the body not covered by clothing. The American Academy of Dermatology (AAD) recommends rubbing the product thoroughly into the skin and notes that more may be needed depending on body size; the US Food and Drug Administration (FDA) also recommends at least 1 ounce to cover the body evenly from head to toe.
| Area | Recommended amount or measure | Source |
|---|---|---|
| Face | At least 1 teaspoon (as the AAD describes it, about the length of the index and middle fingers) | AAD |
| Body, adult | About 1 ounce (a shot glass full) | AAD, FDA |
| Lips | A lip balm with SPF (AAD: at least SPF 30) | AAD, FDA |
| Scalp with thinning hair | Sunscreen or a wide-brimmed hat | AAD |
How long before going outside should you apply sunscreen?
Apply sunscreen about 15 minutes before going outside. According to the AAD, this is how long it takes for the skin to absorb the product and for protection to begin; if you apply it after going out in the sun, your skin is unprotected in the meantime and can burn. In the morning routine, sunscreen is the last skincare step, after moisturiser and before make-up.
How often should you reapply sunscreen?
While outdoors, reapply sunscreen at least every two hours; after swimming, sweating or towel drying, reapply without waiting.
The FDA recommends reapplying more often in water or when sweating. According to the AAD, sunscreen stays on the skin for a limited time; the sun's rays break some sunscreens down, while others clump and lose their effect. According to the FDA, SPF indicates protection relative to the amount of sun exposure, not how long you can stay in the sun, which is why the interval does not get longer with a higher SPF. For products labelled as water resistant, the reapplication time in water and when sweating is the 40 or 80 minutes stated on the label.
How do you reapply sunscreen over make-up?
Reapply sunscreen over make-up with a format that can go straight onto the skin without wiping the make-up off, and without rubbing; the two-hour interval is the same for skin wearing make-up. In short: blot away sweat, glide the stick over the face, ears and neck in short strokes, going over each area more than once, and leave powder or foundation until last. The steps are detailed in our guide to using a sunscreen stick during the day.
On days when you start your make-up with Crush On Pink in the morning, you can reapply with a sunscreen stick that can be used over make-up; the order and amount of the pink-tinted cream under make-up are covered in using a pink sunscreen under make-up.
What are the most common mistakes when applying sunscreen?
The most common mistakes are applying too little, skipping reapplication and forgetting areas; according to the AAD, people who get sunburnt have usually not reapplied, applied too little or used an expired sunscreen.
- Using less, or relying on make-up with SPF: in a study that simulated real use in the laboratory, both sunscreens and make-up products applied in the typical amount, which is less than recommended, measured well below the SPF on their labels, and this loss was proportionally greater for high-SPF products. Make-up does not replace sunscreen; the order of the two layers is covered in our article on preparing skin before make-up.
- Skipping areas: the FDA's list of commonly forgotten areas includes the ears, nose, lips, back of the neck, hands, tops of the feet, hairline and the scalp where hair is thinning. The AAD also reminds you about the neck and legs.
- Spraying directly onto the face: according to the FDA, spray sunscreen should never be applied directly to the face.
How do you build a daily routine with s'hevec?
A daily routine with s'hevec is built on a first layer in the morning and reapplication during the day; your skin type and make-up plans decide the first layer, while the measure is the same whichever product you use: at least 1 teaspoon for the face, 15 minutes before going out.
Just Protected From Sun SPF 50+ Hybrid Sunscreen has a fluid texture that can be measured with a teaspoon, which makes it easier to get the amount right. Matte's Up? SPF 50+ Mattifying Sunscreen is applied to the whole face, including the cheeks, not only the T-zone; do not use less out of concern about shine. You can find all the options, by texture and finish, in our SPF 50+ sunscreens collection. Because they cannot be measured out, sunscreen sticks are not for the first layer in the morning but for reapplying every two hours while outdoors. An SPF 50+ (very high protection) claim does not remove the need to reapply. Which morning product suits which skin type and finish is shown in our table comparing s'hevec sun products by texture, finish and skin type. Before first use, do a patch test on the inner forearm.
When should you see a doctor?
See a doctor if you suspect sun damage, for babies under six months and for a product reaction that does not go away.
- Suspected sun damage: according to the AAD, if you think you are developing sun damage, a dermatologist can examine your skin and give advice.
- Babies under six months: the FDA does not recommend sunscreen at this age; it advises keeping babies out of the sun between 10:00 and 14:00 and consulting a doctor before applying sunscreen.
- A product reaction that does not go away: if stinging, redness or itching starts on the face or around the eyes after a new sunscreen, wash the product off with water and a cleanser and do not use that product again; if the symptoms do not clear within a day or two, see your doctor.
Frequently asked questions
Can you apply less of an SPF 50+ sunscreen?
No. A high SPF does not make up for applying too little; the measure is the same for every SPF.
Do you need sunscreen if you wear a hat and sunglasses?
Yes. The AAD notes that no sunscreen can filter out all UVB rays and recommends shade, protective clothing, a wide-brimmed hat and sunglasses with UV protection together with sunscreen. These measures go alongside sunscreen, not in place of it.
If I am indoors all day, do I still need to reapply every two hours?
The AAD and FDA give the two-hour recommendation for time spent outdoors. However, if hours have passed since you applied your morning product, reapply before going outside.
If you have a light skin tone, should you apply it more often?
No, the interval is the same regardless of skin tone. According to the FDA, people with light skin can absorb more solar energy under the same conditions and burn more easily; on light skin, amount and reapplication matter even more.
How do you apply sunscreen to your back?
For hard-to-reach areas such as the back, the AAD suggests asking someone for help or using a spray sunscreen. When using a spray, the rule on amount and even coverage stays the same.
Sources
- American Academy of Dermatology (AAD). How to apply sunscreen.
- American Academy of Dermatology (AAD). Understand sunscreen labels.
- U.S. Food and Drug Administration (FDA). Sunscreen: How to Help Protect Your Skin from the Sun.
- Kim MA et al. Layering sunscreen with facial makeup enhances its sun protection factor under real-use conditions. Skin Res Technol. 2021.
This content is for information only and does not replace medical advice. s'hevec products are cosmetic products and are not intended for medical treatment. It was prepared by the s'hevec Team on the basis of the s'hevec product data library and the sources listed above.
