Presidential candidates Hillary Clinton and Donald Trump may not have much in common, but there is at least one thing they share: their age. Clinton is 68, and Trump is 70; and although many people in this age group are relatively healthy, others face more health problems than they might have in their younger years.

Both candidates still fall into the "younger older adult" age group of 65 to 74, said Debra Rose, director of the Center for Successful Aging and a professor of kinesiology at California State University, Fullerton. However, she noted that a person's chronological age (the number of years he or she has lived) doesn't always match his or her biological age (how the body's biological systems are functioning).

"You may have an 80-year-old chronologically, who is functioning biologically at the level of a 65-year-old," Rose said. "You might make a comment like, 'My goodness; you're doing really well for your age.'" [8 Tips for Healthy Aging]

It's unclear what Clinton's and Trump's biological ages are, but there are data showing which health problems are most common among people of their chronological age.

In the United States, the top five causes of death among people ages 65 and older are heart disease, malignant cancers, respiratory diseases, strokes and Alzheimer's disease, according to a 2014 report from the Centers for Disease Control and Prevention (CDC).

However, more people are living to at least age 65 than in the past. In the 1970s, about 10 percent of the U.S. population was 65 or older, according to the U.S. Census Bureau. In 2010, this age group made up 13 percent of the total U.S. population, and is projected to constitute 20 percent of the U.S. population by 2030, according to a U.S. Census and 2013 CDC report.

These days, Americans live to an average age of 78.8 years, a 2014 CDC report found.

"The age of 60 is not what the age of 60 was 50 years ago," said Dr. Gisele Wolf-Klein, director of geriatric education at Northwell Health in Great Neck, New York. "For many of them, it's actually midlife."

Still, old age is often riddled with chronic health problems, even for the so-called younger older adults. For instance, doctors recently diagnosed Clinton with pneumonia, and a medical letter on Trump's health shows that he takes a statin to lower his low-density lipoprotein (LDL), or "bad" cholesterol.

While Clinton and Trump don't necessarily have other health problems common in their age group, both Rose and Wolf-Klein listed five pervasive health problems that people older than 65 often experience.

1. Arthritis

Arthritis is an umbrella term for more than 100 conditions that affect joints or the tissues that surround them, according to the CDC. Oftentimes, people with arthritis experience stiffness in or around their joints. About half of adults ages 65 and older have arthritis, according to a CDCreport that looked at data from 2010 to 2012.

2.  Heart disease

Heart disease includes coronary artery disease, which affects blood flow to the heart, and can lead to a heart attack, the CDC says. It also includes high blood pressure (known as hypertension) and stroke. Just under 30 percent of people ages 65 and older had heart disease in 2013 and 2014, the CDC reported. Meanwhile, 8 percent of this age group had experienced a stroke, the report said. [The Best Way to Lose Weight Safely]

3. Obesity

People who have a body mass index (BMI) of 30 or higher are considered obese, according to the CDC. People with obesity are at increased risk of heart disease, stroke, type 2 diabetes and certain cancers, including breast cancer in post-menopausal women, colon and rectal cancer, uterine cancer and kidney cancer, Dr. Seun Sowemimo, a bariatric surgeon and obesity expert at CentraState Medical Center in Freehold, New Jersey, told Live Science in 2015.

About 36 percent of men ages 65 to 74 are obese, and about 40 percent of women ages 65 to 74 are obese, the CDC reported.

4. Vision and hearing problems

As people age, their sight and hearing typically fade. Vision problems that are common in older people include cataracts, age-related macular degeneration, glaucoma and complications from diabetes. About 12 percent of people ages 65 and older had moderate or extreme vision loss, according to CDC data from 2006 to 2008.

Almost 25 percent of people ages 65 to 74, and 50 percent of people 75 and older, have disabling hearing loss, according to the National Institute on Deafness and Other Communication Disorders.

5. Accidents

Even if an older person is healthy, an unexpected fall or accident can lead to broken bones or head injuries. Every year, at least 300,000 people ages 65 and older in the U.S. are hospitalized for hip fractures, and more than 95 percent of hip fractures are caused by falls, the CDC reported. Moreover, after a fall, many people become afraid of falling. This can cause people to do fewer activities, and lose muscle strength as a consequence, the CDC reported.

Original article on Live Science.

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