But other conditions can be serious – sometimes deadly – without causing obvious symptoms, especially in their early stages. Some have even earned the chilling nickname “silent killer.”
Here’s a closer look at eight conditions that don’t always have noticeable signs.
1. High blood pressure
Having high blood pressure means that the force of your blood pushing against your artery walls is consistently too high. Over time, high blood pressure damages the lining of the arteries, and this damage may lead to both heart attack and stroke,cardiologist Dr. Suzanne Steinbaum, a fellow of the American College of Cardiology and the American Heart Association (AHA), told INSIDER.
“The scariest thing is, you don’t know if you have high blood pressure unless you get checked,” she said. The AHA recommends everyone get their blood pressure checked at least once every two years starting at age 20. If you have high blood pressure, your doctor may recommend more frequent testing.
There are some risk factors for high blood pressure that you can’t control, like getting older and having a family history of the condition, Steinbaum added. But basic healthy habits (staying active, eating well, limiting alcohol, not smoking) can help you keep blood pressure in check, according to the Centres for Disease Control and Prevention (CDC).
2. “Silent” heart attacks in women
Steinbaum told INSIDER that, in women, heart attacks can sometimes be “silent.”
“Men are more likely to get crushing chest pain that brings them into the emergency room, whereas women can have much more subtle symptoms,” she said. “Shortness of breath, jaw pain, back pain, fatigue – things that they can sort of blow off and go to bed and not actually know that they had a heart attack.”
Heart attacks may be fatal in and of themselves, of course, but Steinbaum added that multiple subtle attacks can create cumulative damage to a woman’s heart.
“[Women] can present with end-stage heart disease, heart failure, because of these multiple, small silent heart attacks that happened over time,” she said.
She recommended that women with heart attack risk factors seek out medical attention for any heart attack symptoms, including chest discomfort or pain; pain in the arms, back, neck, jaw, or stomach; shortness of breath, nausea; lightheadedness; or breaking into a cold sweat.
“It is so important to go to your doctor and not blow it off,” Steinbaum said.
But people who get gonorrhea may not know they’re infected. Many men and most women with the infection have no symptoms at all, the CDC says.
Left untreated, gonorrhea can cause some serious health issues, including infertility and long-lasting pelvic pain. In rare cases, the infection can spread to the blood and joints and become life-threatening, according to the CDC.
4. Lung cancer
CDC stats show that more Americans die from lung cancer than any other kind of cancer. But most lung cancers don’t cause any symptoms until they have spread elsewhere in the body, according to American Cancer Society (ACS).
The American Lung Association explains that, because there are not many nerve endings in the lungs, tumours may be able to grow without causing pain or discomfort.
When lung cancer does cause symptoms, however, the signs may include a persistent cough, persistent chest pain, hoarseness, shortness of breath or wheezing, lung infections, weight loss, appetite loss, and bone pain.
5. Prostate cancer
“Prostate cancer is a totally silent process unless it is very advanced,” oncologist Dr. Marc Scholz wrote in a post for VeryWell.
There’s a blood test called the PSA that can screen for prostate cancer, but when and how often a man should get it depends on certain individual risk factors. Check out detailed screening recommendations at the Prostate Cancer Foundation’s website.
6. Pancreatic cancer
Early pancreatic cancer typically has no symptoms and spreads quickly in the body, according to the CDC. This means it’s both hard to detect and hard to treat when it is found.
The pancreas is an organ located behind the stomach. It makes enzymes that help break down food and hormones that help regulate blood sugar. Because it’s located deep in the abdomen, pancreatic tumours can grow for years before they cause pain or other concerning signs, Columbia University Medical Center explains.
When pancreatic cancer does cause symptoms, they can vary based on the type of pancreatic cell that’s been affected. In exocrine pancreatic cancer – the far more common type – symptoms may include jaundice (yellowing of the eyes or skin), pain in the belly or back, weight loss, reduced appetite, nausea, vomiting, and, rarely, the development of diabetes, according to the ACS.
7. Cervical cancer
Cancer of the cervix – the lower part of the uterus – is another type of cancer that usually doesn’t show symptoms in its early stages, according to the ACS. Almost all cervical cancers are caused by certain high-risk strains of the sexually transmitted infection Human papillomavirus, or HPV.
Cervical cancer used to be the number one cause of cancer death in American women, according to the CDC, but today the disease is far less deadly. Cervical cancer will cause about 4,000 deaths in 2018, according to the ACS estimates, while breast cancer will cause about 40,000.
The CDC says this decline happened largely because more and more women starting getting a test called the Pap smear, which detects abnormal changes in cervical cells before they become cancerous. The American College of Obstetricians and Gynecologists currently recommends that healthy women start getting Pap smears at the doctor’s office every three years, starting at age 21.
PS: If you’re a woman younger than 26 or a man younger than 21, you may also want to ask your doctor about the HPV vaccine, which protects against some cancer-causing HPV strains.
Hepatitis is an inflammation of your liver. It can be caused by heavy alcohol use, exposure to toxins and certain medicines, or other health conditions, but most cases are caused by a group of viruses, the CDC explains. These viruses can be spread via contaminated food and water, human waste, or the blood and bodily fluids of infected people.
Sometimes viral hepatitis goes away on its own. But for some people, hepatitis becomes a chronic infection that can lead to serious problems, including permanent liver damage, liver failure, liver cancer, and in some cases, death, according to the CDC.
Hepatitis can have signs like fever, nausea and vomiting, fatigue, belly pain, dark urine, and jaundice, but many people with hepatitis don’t have symptoms and don’t know they’re infected, the CDC adds.
In the US, the most common types of viral hepatitis are A, B, and C, which are each caused by different viruses. The CDC has a handy, extensive chart that explains who’s at risk for the diseases, what treatments are available, who should be tested, and who should get vaccinated – there are vaccines that protect against hepatitis A and B.
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