Many sunscreens don’t meet the SPF level printed on the package. (Jeff Greenberg/Getty Images)

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Whether you have fair or dark skin, hit the beach every day or only on vacation, are 16 or 60, you need to use sunscreen if you’ll be in the sun for longer than a few minutes.

But with bottles and tubes covered with claims, “it’s really hard to make sense of what all the terminology means,” says Roopal V. Kundu, an associate professor of dermatology at the Northwestern University Feinberg School of Medicine, who researches how people buy and use sunscreen.

Here, then, is the help you need: seven common terms and what they actually mean — and don’t.

First, however, know that although the federal government requires sunscreen claims to be “truthful and not misleading,” only three of the main claims that consumers see — “SPF,” “broad-spectrum” and “water-resistant” — are strictly regulated.

SPF

Government-regulated? Yes.

SPF, or sun protection factor, is a measure of how well a sunscreen guards against ultraviolet B (UVB) rays, the chief cause of sunburn and a contributor to skin cancer.

SPF 30 is the minimum our experts recommend. But recent Consumer Reports testing found that many sunscreens don’t meet the SPF level printed on the package. So if one of the sunscreens that score higher in our ratings — you can find a list at ­cr.orgsunscreenratings (membership required) — is not available at your local retailer, err on the safe side by choosing a sunscreen labeled SPF 40 or higher.

Broad-spectrum

Government-regulated? Yes.

Products with this label protect against both ultraviolet A (UVA) and UVB rays. UVA rays penetrate more deeply into the skin’s layers and cause damage that can lead to skin aging and skin cancer.

It’s easy to tell how well a broad-spectrum sunscreen protects against UVB rays: Just check its SPF. But you can’t tell how well it protects against UVA rays because the Food and Drug Administration’s broad-spectrum test is pass/fail. So check our ratings; we designed our test to show which broad-spectrum sunscreens provide additional UVA protection beyond the minimum required.

Very water-resistant

Government-regulated? Yes.

The FDA requires “water-resistant” and “very water-resistant” sunscreens to maintain their SPF levels for 40 or 80 minutes of sweating or swimming, respectively.

You won’t see a product sporting a “waterproof” claim; the FDA doesn’t allow it because there’s no such thing. The minute you jump into a pool or begin to sweat, Kundu says, sunscreen starts to run off your skin. That’s why even water-resistant products need to be reapplied as soon as you come out of the water.

Sport

Government-regulated? No.

This means that the product probably works like a water-resistant or very water-resistant sunscreen, Kundu says. But check the label to make sure one of those terms is on the bottle. If not, you can’t be sure you’ll be protected when you sweat or swim.

Dermatologist-recommended

Government-regulated? No.

A sunscreen stamped with this claim (or “doctor-tested”) isn’t necessarily superior to one without it, Kundu says. Because manufacturers aren’t required to adhere to strict definitions for these terms, it’s impossible to know whether the claims are meaningful.

Natural or mineral

Government-regulated? No.

There are no standards for these terms, but they’re commonly used for sunscreens that contain the minerals titanium oxide or zinc oxide as active ingredients. Called physical sunscreens, they protect against UV rays by deflecting them, while chemical sunscreens, such as avobenzone, absorb UV light. Dermatologists often recommend titanium and zinc formulas for children and people with sensitive skin.

But a sunscreen made with mineral ingredients isn’t necessarily better for you than a chemical one. In fact, in the past six years of sunscreen testing, we haven’t found a mineral product that offers top-notch UVA and UVB protection and meets its labeled SPF, says Susan Booth, the project leader for our sunscreen testing. If you still want a mineral sunscreen, we suggest California Kids #Supersensitive Lotion SPF 30+ or Badger Active Unscented Cream SPF 30.

Reef-safe

Government-regulated? No.

Some of the ingredients in sunscreen can damage delicate coral reef systems, which in turn can affect the health of the oceans. Up to 6,000 tons of sunscreens are estimated to wash into coral reefs around the globe each year.

But you can’t be sure you’re making an environmentally friendly choice by using a sunscreen labeled “reef-safe.” Sunscreen manufacturers aren’t required to test and demonstrate that such products won’t harm aquatic life, says Craig A. Downs, executive director of the Haereticus Environmental Laboratory, a nonprofit scientific research organization.

Research suggests that oxybenzone, a commonly used chemical sunscreen ingredient, contributes to coral bleaching, a condition that leaves coral vulnerable to infection and prevents it from getting the nutrients it needs to survive. Mineral sunscreens, on the other hand, appear to be safer for coral reefs than chemical ones, according to the National Park Service. But mineral sunscreens generally aren’t highly rated by CR for screening out harmful UV light. Another alternative is an oxybenzone-free chemical sunscreen.

If you plan to go into the water at the beach, a better environmental bet may be to cover most of your body with UPF (ultraviolet protection factor) clothing — or even just a plain old T-shirt, which previous CR testing has found offers excellent protection. You’ll still have to apply sunscreen to exposed skin, but you’ll need far less.

 Copyright 2018, Consumer Reports Inc.

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