But the truth is that higher-SPF products are only marginally better at shielding you from UVB, according to both the EWG and the Skin Cancer Foundation. SPF 30 blocks nearly 97% of UVB radiation, SPF 50 blocks about 98%, and SPF 100 blocks about 99%.
If studies showed that high-SPF products were better at reducing skin damage and skin cancer risk, the extra chemical exposure might be justified. But they don't, so choosing sunscreens with lower concentrations of active ingredients – SPF 30 instead of SPF 70, for example – is prudent.
Under ideal conditions (like in a laboratory), a sunscreen with higher SPF protection and broad-spectrum coverage offers more protection against sunburn, UVA damage and DNA damage than comparable products with lower SPF values.
“SPF 15 blocks 94% UVB rays, whereas SPF 30 blocks 97% UVB and SPF 50 blocks 98% UVB. Therefore, it's a good idea to opt for SPF 50 even on a daily basis. But not more than that as SPF higher than it can only block an additional 2% of UVB radiation.” Even dermatologist Dr.
Put another way, if your unprotected skin would take ten minutes to show signs of burning, then properly applying SPF 30 sunscreen would slow the rate of burning to the point where it would take 30 times longer, or 300 minutes in total. SPF 15 would take 150 minutes, while SPF 50, 500 minutes.
A sunscreen with SPF 30 will protect you from around 96.7% of UVB rays, whereas an SPF of 50 means protection from about 98% of UVB rays. Anything beyond SPF 50 makes very little difference in terms of risk of sun damage, and no sunscreens offer 100% protection from UVB rays.
The difference between a SPF 40 is you block out 97.5% of UVB radiation and SPF 50 blocks 98%. This is a very small difference for the cost of purchasing a SPF 50. More important than using a super high SPF is using enough sunscreen.
Dermatologists recommend using an SPF of at least 30, which Adarsh Vijay Mudgil, MD, a dermatologist practicing in New York, calls "the magic number". SPF 15 blocks about 93 percent of UVB rays, while SPF 30 blocks about 97 percent of UVB rays. The ADA recommends an SPF of 30 or higher.
The SPF 50 provides adequate protection for your skin by forming a protective layer on the skin that shields it from UVA and UVB rays. The lotion is ideal for skin tones found in India. It absorbs quickly and can also be worn under makeup. It is suitable for all skin types because it is both non-sticky and hydrating.
"For Indian skin, any sunscreen containing SPF 15 and above is preferred. The difference between SPF 15 and 50 is minimal. Sunscreens with higher SPF ratings block slightly more UVB rays, but none offers 100 percent protection," she said.
SPF stands for 'sun protection factor' and the 50 in SPF50 refers to the amount of protection the sun screen offers compared to unprotected skin. SPF 50+ sunscreens are formulated to allow less damaging rays to reach your skin's surface than lower SPF sunscreens.
Experts say sunscreens with an SPF higher than 50 aren't worth buying. They only offer marginally better protection. They might also encourage you to stay out in the sun longer. Instead, choose an SPF between 15 and 50, apply liberally, and reapply often.
Key takeaways: Ultraviolet light from the sun can increase your risk of skin cancer and skin aging. Many safe and effective sunscreens are available, and it's important to use them the right way. Using sunscreen every day — no matter where you live or what color your skin — can protect you from sun damage.
According to the FDA, Sunscreens should reapply every two hours and more often after swimming or sweating. Must remember to follow this instruction, as a failure of this can retard the sunscreen's efficacy.
WHY SPF30 IS THE NEW SPF50
SPF stands for Sun Protection Factor. In theory, an SPF 50 sunscreen would allow users to stay out in the sun fifty times longer than they normally could without sunscreen, while SPF 30 would imply that users can stay out thirty times longer before getting sunburned.
It's non-comedogenic (so won't block pores) and photostable, which means it won't break down when the first UV rays hit your skin. You don't often see a proper sunscreen that can also replace two other integral steps in your skincare routine.
The lighter your skin, the more easily it will get burned by the sun's UV rays. However, all skin types can get sun burned and suffer damage from UV rays. Therefore, dermatologists recommend that everyone use sunscreen of at least SPF 30.
Ideally, look for SPF 30 or higher. Know your skin type: If you have dry skin, choose a face sunscreen with hydrating ingredients, says Dr. Zeichner, like hyaluronic acid or ceramides. If you have oily skin, look for sunscreens that have a matte finish.
Do You Need to Reapply When You're Indoors? As a general rule of thumb, Johns Hopkins medical experts advise reapplying sunscreen every two hours. That said, if you're indoors and away from windows, the need to reapply is less necessary.
Dermatologists recommend using a sunscreen with an SPF of at least 30, which blocks 97 percent of the sun's UVB rays.
As a rule of thumb, use an ounce (a handful) to cover your entire body. Use on all parts of your skin exposed to the sun, including the ears, back, shoulders, and the back of the knees and legs. Apply thickly and thoroughly. Be careful when applying sunscreen around the eyes.
The SPF rating only refers to UVB rays. An SPF 15 sunscreen blocks 93% of UVB radiation, and SPF 30 blocks 97%. After that, the difference in protection is small. SPF 50 blocks 98%, and SPF 100 stops 99% of UVB rays from reaching your skin.
You sunscreen's SPF is only 100% guaranteed for two hours after you put it on. "When we talk about reapplying sunscreen every two hours, that number comes from how SPF is tested," John Zampella, a dermatologist at NYU Langone Health, said.
In general, you should reapply sunscreen every two hours for consistent protection. However, there is an exception to the rule—if you're sweating or swimming you need to apply more often. To make sure you're protected even when you're active, you should reapply sunscreen at least every 80 minutes.
Sunscreen only prevent sun tanning, it will not make fair. You should use Depigment creams to remove the pigment issues.