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Play safe in the sun! Sunscreen is a must-have skincare product. It protects you from UVA and UVB rays of the sun that cause tanning, premature aging, sunburn and skin cancer.    


  • What is SPF?
  • How does SPF work?
  • What are the different types of SPF?
  • What is broad-spectrum SPF?
  • How to apply sunscreen
  • Who needs sunscreen?
  • Do sunscreens with high SPF protect you better?
  • How to choose a sunscreen
  • Do you get Vitamin D with sunscreen?
  • Physical or Chemical sunscreen? Which one is better?
  • Sunscreen vs Sunblock: What's the Difference?
  • Benefits and potential risks of wearing sunscreen

What is SPF?

SPF or Sun Protection Factor is a relative measure of how long a sunscreen will protect you from the sun’s UVB rays.

The SPF number indicates the number of hours or minutes of protection (depending on how fast your skin burns naturally and solar exposure). (1)

For example, if your skin takes 10 minutes to burn normally, a sunscreen with an SPF30 will protect you for 5 hours (10X30) from the sun’s rays. However, it is recommended to reapply sunscreen every 2 hours. This is because the efficacy of a sunscreen depends on solar exposure as well.

The rays of the sun are stronger during peak hours. Your skin may burn faster at 12 pm as compared to 8 am. 

The SPF number also tells us how much percent of the UVB rays the applied product will absorb. A sunscreen with SPF15 will absorb about 93% of the sun’s UVB rays. A sunscreen with SPF30 will absorb about 97%.

The highest a sunscreen can absorb is 98% of the sun’s UVB rays. This comes with SPF50 sunscreens.  No sunscreen absorbs 100% of the sun’s UVB rays.

How does SPF work?

UVB rays tend to damage the epidermis (outer layers of the skin). UVA rays seep into the skin and reach its dermal layers. SPF in sunscreen absorbs or reflects these rays to protect the skin. It does not allow these rays to reach the skin. 

What are the different types of SPFs?

There are two types of SPFs.

Physical or mineral SPF:

Physical or mineral SPF forms a layer on the skin. They are also called sunblocks because of their ability to block UV rays from entering the skin. They reflect sunlight. Physical sunscreens are recommended for people with acne-prone skin. They don’t clog pores. 

However, they may not be the best option when you’re wearing makeup. They are thick and appear greasy on the skin.

Chemical SPF:

Chemical SPF sinks into the skin and absorb the UV rays of the skin. Chemical SPF appears thinner and less greasy on the skin. 

They are suitable to wear before applying makeup. Chemical sunscreens are a good option if you have dry skin. 

What is a broad-spectrum SPF? 

A broad-spectrum sunscreen protects you from UVB and UVA rays of the sun

A broad-spectrum sunscreen protects you from UVB and UVA rays of the sun

Broad-spectrum SPF implies a sunscreen that protects you from both UVA and UVB rays of the sun. A regular sunscreen protects your skin from UVB rays of the sun. 

UVA rays penetrate deep into your skin and can cause skin cancer, tanning and premature aging. Sunscreens labeled “broad-spectrum” absorb both the rays of the sun and are ideal for daily use.

How to apply sunscreen

If you don’t apply your sunscreen properly, your skin will burn. 

Sunscreens come in the form of gels, creams and lotions. Whatever you choose, make it a point to apply a thick coat of the product on to your skin. (2) Cover all areas you think will be directly exposed to the sun. 

According to dermatologists, you should apply sunscreen 30 minutes before you step-out. Reapply sunscreen every 2 hours.

Water-resistant sunscreens last for up to 40 minutes. If you love swimming or sweating it out, apply sunscreen 30 minutes prior to your activity. Reapply immediately after finishing your activity. 

How much sunscreen should you apply?

On an average, one ounce (equivalent to a shot glass) should be enough to cover your whole body. (3)

How often should you apply sunscreen?

Dermatologists recommend applying sunscreen every time you step out in the sun for more than 20 minutes. 

If you are out in the sun on a daily basis, apply sunscreen everyday 15-30 minutes before leaving your house. It is recommended to reapply sunscreen every 15-30 minutes when you’re exposed to the sun. (4)

If you sweat a lot or enjoy swimming on a regular basis, apply water-resistant sunscreen. Re-apply every 40-80 minutes and as soon as you dry yourself up.

What is the best time to apply sunscreen?

Ideally, you should apply sunscreen every time you expose your skin to the sun. However, if you’re not a sunscreen person and don’t really enjoy the feel of it, make sure to apply it during peak hours. Peak hours of the sun in India last between 10 am to 2 pm. These are the hours when the sun’s rays are the strongest. 

Where should you apply sunscreen?

Apply sunscreen on parts of your body that are directly exposed to the sun. This usually includes your face, neck, back, arms and legs. If you’re in the mood to hit the beach or go swimming, preferably apply it on all parts of your body.

Who needs sunscreen?

A common misconception is that dark skinned people do not require sunscreen.

People with dark skin have more melanin. Melanin protects the skin from some amount of UV damage. However, melanin is not effective in protecting the skin from UVA rays (5)

Sunscreen should be worn by everybody. Most people use sunscreen to prevent tan and burns. Sunscreen is also essential to protect the skin from a range of other skin conditions. 

Skin cancer, sun burns, tanning, wrinkles, dehydration can all be the result of direct exposure to the sun. Sunscreen helps prevent these skin conditions. 

Babies below 6 months should not wear sunscreen. They may react to the harsh chemicals of the product. (6) However, the rays of the sun can also damage a baby’s skin. Avoid taking your baby out in the sun before 6 months.

Do sunscreens with high SPF protect you better?

Higher numbers sound better; always. When it comes to sunscreens, high SPF numbers do not indicate double protection. For example, a sunscreen with SPF15 protects you from 93 percent of the sun’s UV rays. SPF30 protects you from 97 percent. 

Experts worry that people may be misguided into believing that high SPF offers extremely high protection. This may encourage people to stay for longer hours in the sun (7).

However, some studies suggest that a sunscreen above SPF70 can offer additional clinical benefits. Research also says that these are more effective than SPF30 or SP50 sunscreens (8)

How to choose a sunscreen

  • Form of sunscreen 

Sunscreens come in the form of sprays, lotions, gels, creams, butters, sticks, oils and pastes. Choose a sunscreen that you’re comfortable applying. 

If you have acne-prone skin, a gel-form would be a good option. If you have young children, a spray would be ideal. If you wear makeup regularly, pick a sunscreen that doesn’t appear greasy. (9)

  • Active ingredients

Active ingredients in a sunscreen protect you from UVA and UVB rays of the sun. Choose a sunscreen that has suitable and authorized ingredients.

  • Broad-spectrum 

Most sunscreens protect you from UVB rays of the sun that contribute to sunburn and thickening of the skin. 

UVA rays cause tanning and premature aging of the skin.

Direct exposure to UV rays regularly can lead to skin cancer. (10) (11)

  • Know your skin

Get yourself a sunscreen that suits your skin type and doesn’t interfere with your skin issues. If your skin is prone to acne, mineral sunscreens are a good option. They prevent clogged pores. 

If you have dry skin, chemical sunscreens are ideal. Conduct a patch-test before applying sunscreen to your whole body. 

  • SPF number

Before you buy a sunscreen, take a look at the SPF number. This will determine how long the sun will protect you for. 

If you’re adventurous and love staying out in the day for long hours, buy a sunscreen with a higher SPF number like SPF50! If the only time you’re out in the sun is during your ride from home to office, purchase a sunscreen with a low SPF number. 

Dermatologists recommend a sunscreen of at least SPF15 for everybody. 

  • Purchase a water-resistant sunscreen

Considering the humidity levels of India, water-resistant sunscreens are a good option. 

Our skin expels water through sweat. If you’re particularly active and sweat a lot or spend long hours swimming, choose a water-resistant sunscreen. Re-apply it every 40-80 minutes. 

  • Conduct a patch-test

Before applying sunscreen on your whole body, conduct a patch-test. Look out for any allergic reactions. If your skin feels itchy, red or patchy after applying the product, wash it off. Purchase a sunscreen based on your skin type.

  • Check the expiration date

If a sunscreen has crossed its expiration date, don’t buy it. It will not offer the same kind of protection it claims to. Also, make it a point to inform the store manager about this!

  • Purchase a broad-spectrum sunscreen

Most sunscreens protect us only from UVB rays of the sun. These sunscreens prevent our skin from burning. However, they do not protect it from UVA rays. These rays are responsible for tanning and premature aging. Get yourself a sunscreen that protects you from UVA and UVB rays. (12)

  • Skin type matters

Always purchase a sunscreen based on your skin type. If you particularly have acne-prone skin, buy a sunscreen that is recommended for your skin type to avoid breakouts and clogged pores.

Do you get Vitamin D while wearing sunscreen? 

UVB rays are essential and play a vital role in producing Vitamin D. 

Some studies suggest that wearing an SPF30 sunscreen or a higher number decreases the Vitamin D production in the body by 95 percent. (13)

A recent study showed that wearing a clinically prescribed sunscreen (SPF15) has a minor impact on Vitamin D production in the body. (14)

It is recommended to wear a sunscreen with SPF15 regularly. Health problems caused by UV rays should be more of a concern than Vitamin D deficiency. 

People with a darker skin tone have higher sun protection. However, their body takes more time to produce an adequate amount of Vitamin D. They may be required to stay in the sun three to five times longer than a white-skinned person. 

Physical or Chemical sunscreen? Which one is better?

Both physical and chemical sunscreens are effective in protecting your skin. Choose a sunscreen that suits your skin.

Both physical and chemical sunscreens are effective in protecting your skin. Choose a sunscreen that suits your skin.

physical/mineral sunscreens

Pros of using physical/mineral sunscreens

  • Ideal for sensitive/acne-prone skin
  • Forms a coat on top of the skin, less likely to clog pores
  • No wait-time is required
  • Offers protection against UVA and UVB rays, naturally broad-spectrum

Cons of using physical/mineral sunscreens

  • Not “makeup friendly” as it forms a white coat on top of the skin
  • Constant re-application may be needed as it can rub off easily
  • Has to be applied generously and accurately to offer full protection

Chemical sunscreens

Pros of using Chemical sunscreen

  • Thinner and easy to rub into the skin
  • Works well under makeup and spreads easily on the skin
  • More water-resistant as compared to physical sunscreen
  • Available in ‘broad-spectrum’ to protect skin from UVA and UVB rays

Cons of using a chemical sunscreen

  • Can clog pores 
  • Requires a 15-30 minute wait time
  • Can irritate the skin and cause redness
  • Can cause irritation and stinging sensations 

Both physical and chemical sunscreens effectively protect your skin against UV rays. Based on your skin type and other preferences, you can decide on what sunscreen you’d like to go for. 

Sunscreen vs Sunblock: What's the Difference?


A sunscreen penetrates through the skin. Sunscreens are designed to protect the skin against UV rays of the sun. They absorb the rays of the sun.


Sunscreens sink into the skin. It is required for you to rub the product into your skin. Sunscreens may appear greasy but usually don’t show on the skin. 


A sunblock doesn’t sink into the skin. It acts as a shield by sitting on top of the skin and reflecting away the sun’s rays. Sunblocks contain zinc oxide or titanium oxide.


Sunblocks appear prominently on the skin. A white coat can usually be seen on the skin after applying the product. 

Benefits and Potential Risks of wearing sunscreen


  • Protects us from UVA and UVB rays of the sun
  • Allows us to soak up the sun without harming our skin and its appearance, preventing premature aging, burning and tanning
  • Prevents dehydration of the skin

Potential risks

  • Greasy appearance

The most annoying part of wearing sunscreen is how it makes our skin look. Spray sunscreens are a good option if you’re out for a day party or event, once in a while.

  • Clogged pores

Sunscreens can contribute to acne breakouts by clogging your pores. If you have acne-prone skin, pick a physical sunscreen for yourself. 

  • Wait time

Sunscreens should be worn 30 minutes before you step-out in the sun. 

  • Interferes with Vitamin D production

Some studies suggest that wearing sunscreen can reduce Vitamin D production in the body  (15) 

Wearing sunscreen can at times frustrate you. It is an essential product to maintain skin health. Spend time at your cosmetic store, try out different sunscreens to determine their feel and look. Pick one that suits your preference and skin type!