There is good health and fitness advice on the web—here's how to find it

Don't just assume that sore throat is a sign of cancer.

sick man

Feeling sick

Tempted to look up your symptoms online? Stick to trustworthy health sources.Gerd Altmann via Pexels

At times, we all rely on the internet to diagnose our symptoms. But finding trustworthy health advice isn't easy. For every website that blames your sore throat on allergies, there's an app that thinks it might be cancer. Among the vast multitude of online voices—a search for "shallow breathing" alone turns up more than 30 million Google results—which ones can you rely on?

Don't despair. In this guide, we'll point you toward the best medical resources on the internet. Any one of these websites or apps will give you health advice you can rely on.

1. Medline Plus

What you get: Medline Plus isn't the type of website you visit to type in symptoms and see what you've come down with. Instead, it offers advice on broad topics like general wellness and prescription drugs, as well as more specific issues like tick bites and pneumonia. Each page also provides links to related information, such as relevant articles and clinical trials. If you already have a known or suspected diagnosis, this site can prove an invaluable resource.

In addition to text, Medline Plus provides a few multimedia resources. Helpful videos demonstrate the signs of certain conditions and how they affect the body. You can also try out online health-check tools to monitor your alcohol use, decide whether or not you need a hearing test, calculate your Body Mass Index (BMI), and more.

Why we trust it: Two extremely credible sources—the National Library of Medicine, the largest medical library in the world, and the National Institutes of Health (NIH)—run Medline Plus and vet the facts on the site. Because the site's funding does not rely on advertising or commercial companies, you know that biased sources haven't influenced its coverage.

Medline Plus: website (free)

2. Family Doctor

What you get: Before we dive in, let's put this up front—when it comes to diagnosing illness, nothing beats a visit to a qualified physician. But. If you want to know what certain symptoms might indicate, Family Doctor is a far better option than Dr. Google. When you visit this site's Symptom Checker, you choose your general problem from a list and then answer a few straightforward yes or no questions about your specific experience. After that, you receive an honest answer, written in a cautious and professional tone, along with a suggestion for how to treat your problem (which often points you back to consulting a healthcare expert).

On top of that, the site presents a host of information on diseases and conditions. For each item, you can read about everything from initial symptoms to causes to treatments. You can also check out Family Doctor's tips for keeping yourself well and preventing problems in the first place. All this advice comes in a very readable style so we non-professionals can understand it.

Why we trust it: The site has backing from the philanthropic arm of the American Academy of Family Physicians (AAFP). Doctors and professional writers produce the content, under the guidance of a medical review panel. The result is educational rather than commercial—Family Doctor doesn't try to sell anything to its readers.

Family Doctor: website (free)

3. KidsDoc

What you get: Again, if any family member feels ill, your doctor is your best source of advice. But if that's not an immediate option, KidsDoc is one of the best resources we've found for diagnosing children. When you download the apps, you can use keywords to search for and identify symptoms and injuries. KidsDoc's answers will quickly give you an idea of whether you should manage the condition at home or head straight to the ER. The clear layout, understandable advice, and illustrative pictures make it easy to diagnose problems.

The KidsDoc app comes from the HealthyChildren.org website. Although the aforementioned diagnostic tools are limited to the app, the site offers a wealth of information, including age-related advice for child health and safety, details about various conditions, answers to common medical questions, and a tool to help you find a pediatrician.

Why we trust it: The American Academy of Pediatrics, along with some 66,000 pediatricians, developed both the site and the apps. These experts use scientific research to back up their advice. And their HealthyChildren-KidsDoc network aims to promote healthy living, not sell a product or service.

KidsDoc: website (free), Android app ($2), iOS app ($2)

4. John Hopkins Health Library

What you get: Rather than diagnosing issues, the John Hopkins Health Library website focuses on providing understandable, jargon-free information. It teaches you about diseases and conditions from cancer to tonsilitis, and also describes various medical tests, procedures, and treatments. Plus, the site can help prevent issues from getting started in the first place with advice on nutrition and avoiding common health problems, tailored to a reader's gender and age.

The site can't diagnose problems, but you can manually check lists of symptoms if you already have an idea of what you're looking for. Once you get a diagnosis, you can keep informed by reading up on your problem's traits and treatment.

Why we trust it: As the name suggests, this site comes to us from John Hopkins Medicine, one of the largest health enterprises in the world. The organization is committed to improving healthcare and education, and it does not run this site as a commercial endeavor.

John Hopkins Health Library: website (free)

5. Drugs.com

What you get: After a diagnosis, it's time to treat your problem. If you need more information on a medication, head to Drugs.com. The site and its associated apps describe more than 24,000 prescription drugs, over-the-counter medicines, and natural remedies, explaining how these substances work, how much to take, and known side effects. That said, Drugs.com is not an online pharmacy, and it can't tell you what to take or provide prescriptions.

On top of general information, Drugs.com offers a few handy tools. A pill identifier lets you work out what that random medication might be based on its imprint, shape, or color. In addition, the Interactions Checker helps you spot the medications and food that might not play well together.

Why we trust it: Despite its name, Drugs.com is not funded by pharmaceutical companies, just by clearly-marked advertising. This long-running and independent resource pulls its information from experts like the American Society of Health-System Pharmacists, the Mayo Clinic, and Stedman's Medical Dictionary.

Drugs.com: website (free), Android app (free), iOS app (free)

6. Ada

Ada app

Ada

Artificial intelligence tackles your diagnosis.Ada

What you get: Unlike the other items on this list, the Ada app uses artificial intelligence to spot patterns in your symptoms that you might otherwise overlook. It will feed you a few simple questions, personalized to your particular situation. Then it will list potential conditions—along with their symptoms and treatments—that might ail you. It provides clear, considered advice that draws on a database of more than 1,500 conditions. However, Ada's take is not an official diagnosis, so you should use it to complement rather than replace your doctor.

Why we trust it: An independent startup—not funded by advertising or sponsorship—developed Ada with help from more than 100 doctors and scientists. When Wired UK tested three diagnostic apps, Ada out-performed its competitors Babylon and Your.MD. And users are also positive, giving very high ratings to both the Android and iOS versions of the app.

Ada: Android app (free), iOS app (free)

7. Centers for Disease Control and Prevention (CDC)

What you get: Don't visit the CDC's online resources to figure out why you have a temperature at four in the morning. Instead, consult the U.S.'s leading national public health institute to learn more about medical conditions, healthy living, and much more. This resource, like a few others we've mentioned, comes in handy for looking up details of a newly-diagnosed condition and getting advice about minimizing disease risk. But it also goes beyond standard medical advice.

In addition to describing diseases, the CDC website and its associated apps provide detailed data like maps of diabetes patients by county. On top of addressing health issues, they explain how to survive natural disasters and travel safely. We particularly like the latter section, which gets you up to speed on the current health risks you'll face if you visit specific countries—and how to avoid them.

Why we trust it: The CDC is a government agency without ties to commercial companies or the pharmaceutical industry. That means the state-funded site and apps rely on data from official, scientific sources. The comprehensive information also receives regular updates.

CDC: website (free), Android app (free), iOS app (free)