Image source: Getty Images.

Medicare helps to pay for the healthcare expenses of more than 50 million Americans, making it one of the country's most popular and important social programs. Learning all the ins and outs of the system can be a bit complicated, but if you rely on the program for your carem then it's worth putting in some effort to make sure you know what's covered. 

With that in mind, we asked a team of Fools to highlight a little-known Medicare benefit. Read on to see what they had to say.

Tackling depression

Todd Campbell: Once a year, every Medicare Part B recipient can receive free depression screening from his or her primary-care doctor.

That's important, because one in six seniors suffers from depression, and many of those seniors are either undiagnosed or under-treated for their disease. According to WebMD, only 10% of chronically depressed seniors receive the treatment they need for their disease.

Depression is a particularly serious matter for seniors, because studies show that it can lead to other health problems, such as cardiac diseases, and it can increase the risk of death. Depression has been linked to poorer outcomes among nursing-home patients, and sadly, seniors' suicide rate is higher than it is for any other age group. Clearly, Medicare's depression screening is critically important to maintaining health in your golden years.

While depression can occur in elderly patients for various reasons, depression can coincide with chronic diseases or an injury that limits a retiree's mobility. Therefore, if you or a loved one is a Medicare recipient who has health concerns, taking advantage of Medicare's annual depression screening is a must.

Thank you for not smoking

Brian Feroldi: While smoking rates have been falling for decades, nearly half a million Americans die each year from tobacco use, making it the leading preventable cause of death in the country.

While learning to kick the habit later in life can be a challenge, it's never too late to give it a try. Beyond the obvious cost savings, studies show that quitting will substantially lower your chance of developing a wide range of medical diseases, even if you've been smoking for decades.

Image source: Getty Images.

Thankfully, the government recognizes all of the advantages that come from quitting, and they've set Medicare up to help you. Anyone who uses tobacco and has Medicare Part B coverage can get up to eight smoking-cessation visits covered over a 12-month period. The only stipulation is that the visits are with a qualified doctor or other Medicare-recognized practitioner.

These visits will not cost you a penny out of pocket, so if you're a tobacco user who wants to quit for good, make sure you take advantage of this Medicare benefit.

A valuable annual wellness visit

Selena Maranjian: One Medicare benefit that many people don't realize is a benefit is the annual wellness visit that you're entitled to at no cost to you. It may not seem that important, but it really is -- and all enrollees would do well to take advantage of it. It's available to anyone covered by Part B, and Medicare Advantage plan enrollees get the benefit, too.

You generally go for a wellness visit with your primary-care physician once a year, even when you're feeling fine. These visits give you and your doctor a chance to review your health and see where attention might be needed or improvements might be made. Since you're not going in because of back pains or dizziness or a twisted ankle, the focus is on your overall health.

Annual wellness checks involve your filling out a health risk assessment questionnaire, which your doctor will use as he or she reviews your condition. A key goal will be to develop or update a plan to help prevent your developing any diseases or disabilities. Your doctor will probably review your medical history and that of your family, take standard measurements (such as your height, weight, and blood pressure), review the medications you're taking, assess you for any cognitive issues, order any appropriate screenings, and offer advice. It's a particularly good time to ask any questions you may have about your health and possible treatments.

Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.