"Awareness and treatment of hypertension (high blood pressure) in older adults has improved significantly over the past 10 years," Dr. Anthony Kouri, MD, an orthopedic surgeon at the University of Toledo Medical Center, tells Bustle. But you might not realize that you can have high blood pressure even at an early age. Kouri says that 50% of young adults diagnosed with hypertension still go untreated, and this can lead to heart disease and increased mortality. Because hypertension usually doesn't present with symptoms, it's critical to get an annual checkup so that your doctor can make sure that you don't have the condition, Kouri says.

If you've spent time with grandparents or other older folks, you've probably learned that vitamin D is crucial for bone health in older adults. A deficiency in the vitamin can be a real issue for people who are still young as well, Kouri says, and up to 50% of young adults are deficient in vitamin D.

What does the vitamin even do? It helps your immune system work properly, helps your nerves function, and helps your body absorb calcium, he says. Making sure that you're getting enough vitamin D in your 20s means that you'll be at a lower risk of osteoporosis and fractures later on, so now is the time to start. Foods like salmon, tuna, egg yolks, milk, and fortified orange juice are all rich in the vitamin, but if you still aren't absorbing enough, your doctor might recommend a supplement.

"The biggest trend I've been noticing is the increased incidence in skin cancer diagnoses for my patients in their 20s and 30s," Dr. Adarsh Vijay Mudgil, MD, a board-certified dermatologist and dermatopathologist specializing in non-invasive face and body rejuvenation, tells Bustle. "Much of this is attributable to increased use of tanning beds, which is literally the absolute worst thing you can do to your skin," he says. If you notice scaly red spots, or pimple-like lesions that don't go away on their own, those might be signs of skin cancers. It's also important to watch out for melanomas, which generally present as irregular looking moles which can be asymmetric, have irregular borders, multiple colors, and large diameters, Mudgil says. If you notice something out of the ordinary, see a dermatologist to get it checked out.

When you're still in your early 20s or 30s, you might not have even decided whether you want to get pregnant one day. But being aware of infertility conditions early can help you understand your options. "Infertility is a health condition that many young people do not expect can impact them, especially before they are trying to start a family," Dr. Robert Mordkin, MD, FACS, a clinical physician specializing in urology and chief medical officer for LetsGetChecked, tells Bustle. But the condition is fairly common and can be easily tested, he says. If you have an infertility condition, you might experience a hormone imbalance or irregular menstrual cycles. After receiving a diagnosis, there are a number of treatment options available to you if you choose to pursue them, like hormone medications, IVF, and artificial insemination, Mordkin says.

"Liver disease is a condition that can impact younger patients, despite the general assumption that this illness is reserved for the older population," Mordkin says. "Due to factors such as excessive alcohol consumption, Hepatitis and hemochromatosis, liver disease can impact individuals as young as their 20s or 30s." Some symptoms of liver disease include a loss of appetite, swelling of the stomach, dark urine, light-colored stool, nausea, fatigue, and jaundice, he says. If you notice these symptoms, talk to your doctor, who may recommend treatment options like lifestyle changes, medications, long-term liver repair treatments, and in serious cases, a liver transplant.

"One health condition that I think is frequently overlooked by people in their 20s and 30s is sleep apnea," Dr. Jagdeep Bijwadia, MD, a pulmonologist specializing in sleep studies and chief medical officer at Beddr, tells Bustle. "People of all ages and body types can have sleep apnea." When you have this sleep disorder, you stop breathing multiple times throughout the night, and you could be at risk for irregular heartbeat, high blood pressure, type 2 diabetes, depression, heart attack, stroke, and sudden death, Bijwadia says. If you find yourself waking up gasping for breath or are inexplicably exhausted during the day, check in with your doctor.

Traditionally, autoimmune diseases like multiple sclerosis, lupus, Crohn’s disease, rheumatoid arthritis, and Type 1 diabetes, have been diagnosed primarily in people in their 40s and older. "But now we’re seeing these occur in people in their 20s and 30s," Gedroic says. Things like pesticides and herbicides used in your foods, environmental pollution, and even too much sugar, can throw the body out of whack and set it up for autoimmune diseases, she says. Beginning warning signs of an autoimmune disease include symptoms like fatigue, mild joint pain, and less mental acuity, so mention anything out of the ordinary to your doctor so that they can treat a problem before it's full-blown.

While you can't anticipate exactly what your health future will look like, being informed about what to watch out for is important. And having a doctor you trust can bring you lots of peace of mind.