Skip to content

I'm a Doctor and Here's the #1 Sign You Have a Deadly Illness

Experts share five deadly illnesses to know about and symptoms to watch out for. 
FACT CHECKED BY Emilia Paluszek

We are surrounded by things that can kill us at any given time and our immune system works around the clock to protect us from some of those things like bacteria, infection and disease. Even though our body fights to keep us healthy, in some situations without treatment we can't get better. For instance, "Melioidosis is a disease that strikes fear in those who've heard of it," NPR reports. "Doctors in Southeast Asia and Northern Australia know it as a stubborn, potentially deadly infection that causes pneumonia, abscesses and, in the most severe cases, organ failure. Without treatment, it can kill within 48 hours…For decades, melioidosis seems to have lurked under the radar of global public health organizations. "For everybody, it was a disease of southeastern Asia and Australia," says Dr. Eric Bertherat of the World Health Organization. "But we are discovering that this disease is present in many other regions worldwide."

As much as medicine has advanced, there's still plenty of deadly diseases out there, but there are several fatal illnesses we can partially prevent by practicing healthy habits, like heart disease, which is the leading killer in the United States. Leslie Cho, M.D., Section Head for Preventive Cardiology and Cardiac Rehabilitation at Cleveland Clinic states, "Heart disease is 90 percent treatable – everyone can prevent heart disease anywhere in the world, especially by eating foods that are low in salt and cholesterol, exercising regularly, and not smoking. Even if a person has a family history of heart disease, we can still prevent and treat heart disease thanks to incredible advances in medicine."

That said, there are illnesses like mental disorders such as substance use disorder that can be more difficult to prevent, but treatment is available. According to the Centers for Disease Control and Prevention, "There were an estimated 107,622 drug overdose deaths in the United States during 2021, an increase of nearly 15% from the 93,655 deaths estimated in 2020. The 2021 increase was half of what it was a year ago, when overdose deaths rose 30% from 2019 to 2020." Eat This, Not That! Health spoke with experts who share deadly illnesses to be aware of and signs to watch out for. Read on—and to ensure your health and the health of others, don't miss these Sure Signs You've Already Had COVID.



Sad woman drinking wine at kitchen.

Dr. David Seitz MD, and Medical Director for Ascendant Detox tells us, "Addiction is a chronic, relapsing disorder characterized by compulsive drug or alcohol use despite harmful consequences. Those who suffer from addiction often feel as though they cannot control their use of the substance, even when it is causing them problems in their personal and professional lives. Addiction can affect anyone, regardless of age, gender, race, or socioeconomic status. In some unfortunate cases, when substances are abused for long periods of time, addiction can lead to death.

Some common signs and symptoms of addiction include physical, behavioral, and emotional changes. These may include weight loss or gain, change in appetite, poor hygiene, red or glazed eyes, constant fatigue, changes in sleeping patterns, mood swings, irritability, and unpredictable and risky behavior. If you or someone you know is displaying these signs, it is important to seek help as soon as possible, as addiction is a very serious and potentially life-threatening condition that requires professional treatment."


Alzheimer's Disease

older man with dementia talking to doctor
Shutterstock / Robert Kneschke

Dr. Seitz says, "Alzheimer's disease is a progressive neurological disorder that affects cognition and memory. It is the most common type of dementia, accounting for 60-70% of all cases, according to the WHO. Dementia is also ranked as the seventh leading cause of death globally. Alzheimer's disease typically affects older adults, with the majority of cases occurring in people over the age of 65. However, signs of the disease can begin to develop in people in their 40s and 50s.

The early signs of Alzheimer's disease are often subtle and may be mistaken for normal age-related changes. However, as the disease progresses, symptoms will become more severe and noticeable. These may include memory loss, confusion, difficulty speaking or writing, reduced ability to perform familiar tasks, and impaired judgment. If you or a loved one is exhibiting any of these symptoms, it is important to see a doctor for a proper diagnosis."

There are several lifestyle choices that greatly reduce the risk of Alzheimer's such as not smoking, eating the Mediterranean or DASH diet, keeping the mind active, staying socially engaged, limiting alcohol consumption and exercising at least 150 minutes a week. 

Kent Probst, personal trainer, kinesiotherapist and bodybuilder with Long Healthy Life shares, "The benefits of exercise are virtually endless regarding how resistance exercise improves cognitive function.  How weight training helps cognitive function:

Increased blood flow to the brain.

Increased angiogenesis (formation of new blood vessels)

Increased neurogenesis (formation of new neurons)

Increased production of neurotrophins (proteins that improve survival of brain cells and help with brain plasticity).

During weight training, something else occurs – greater production of neurotransmitters.  Neurotransmitters such as serotonin, gamma-aminobutyric acid, and acetylcholine function to help learning, memory, sleep and mood."


Chronic Kidney Disease

Man with kidney problem

Dr. Ashte Collins, MD, Internal Medicine, Nephrology and Associate Professor of Medicine at The George Washington University explains, " Chronic kidney disease (CKD) affects 11% of the global population, and roughly one in seven Americans. It remains the 10th leading cause of death worldwide. It may be fully preventable in some cases and certainly treatable in most cases. The kidneys are critical organs that can filter waste and toxins out of one's body, help control blood pressure, balance electrolytes, and keep bones healthy.

Diabetes mellitus remains the leading cause of chronic kidney disease (CKD) and end-stage kidney disease (ESKD) in the United States, contributing to hypertension and/or proteinuria (loss of protein into the urine) from the kidneys, which causes inflammation and scarring within the kidneys. The longer a person has diabetes, especially if uncontrolled, the more likely one is to develop CKD.

Early stages of CKD are completely asymptomatic. Kidney function is very much like a tank of gas in a car. The car will basically run the same whether the tank is full, half-full, or even quarter full. When the tank gets to "empty", the car stops, and by that time, too much damage has occurred to reverse the process of CKD progression to end-stage kidney disease (ESKD). 

People of an ethnic minority heritage, low socioeconomic status, and those with diabetes, hypertension, cardiovascular disease, smoking, obesity, and older age are all at higher risk of developing CKD than the general population. 

Most people are asymptomatic until late stages of CKD, so screening with a blood test to measure one's glomerular filtration rate (GFR) is critical. This test measures the rate at which the kidneys remove certain wastes from the bloodstream. Another useful test is a urinalysis with urinary albumin. Albumin spillage into the urine from the kidneys can precede a drop in GFR by months to years, so screening for albuminuria is vitally important yet underutilized in clinical practice."

Felicia Speed – LMSW, Corporate Director of Social Work Services at Fresenius Medical Care North America adds, "CKD is sometimes referred to as a "silent" condition because it's hard to detect—and 9 out of 10 adults with CKD are unaware they have it. That's because its signs and symptoms tend to, unfortunately, occur after the condition has progressed and kidney damage has occurred. It's important to contact your doctor immediately if you notice the following symptoms:

Changes in urination: Healthy kidneys help filter blood to create urine. When the kidneys don't function well, urination issues may occur such as needing to urinate more often or seeing blood in your urine. Your urine may also appear foamy or bubbly, an early sign that protein is leaking into your urine due to damaged kidneys.

Fatigue: Reduced kidney function can lead to a buildup of toxins in the blood that causes you to have a lack of energy or feel overwhelmingly tired. CKD may also cause anemia, which can make you feel tired or weak due to having too few red blood cells.

Itching: Dry and itchy skin may indicate an imbalance of minerals and nutrients in your blood. Itching is often caused by high blood levels of phosphorus.

Swelling in your hands, legs, or feet: When your kidneys aren't removing excess fluid and sodium from your body, swelling may occur in your feet or other lower extremities.

Shortness of breath: Extra fluid can build up in your lungs when your kidneys aren't removing enough fluid, which may cause shortness of breath. CKD-induced anemia may also cause breathlessness.

Pain in the small of your back: You may experience localized pain near your kidneys that doesn't change or that becomes worse when you move or stretch. The kidneys are located on either side of your spine in your lower back, and kidney problems can cause pain in this area. Back pain may also be due to an infection or blockage of the kidneys, which can lead to kidney damage.

Decreased appetite: A buildup of toxins due to impaired kidney function may cause you to lose your appetite, whether because you feel full or too sick or tired to eat.

Puffiness around your eyes: Protein leaking into your urine may cause persistent puffiness around the eyes, an early sign of kidney disease.

Muscle cramping: Impaired kidney function can cause electrolyte imbalances, such as low calcium levels or high phosphorus, that may lead to muscle cramping.

High blood pressure: Excess fluid and sodium built up as a result of the disease can cause higher blood pressure, which can also damage blood vessels in the kidneys and lead to a worsening of the condition over time."


Heart Disease

Dr. Seitz states, "Heart disease is one of the leading causes of death in the United States. It is a term used to describe several conditions that affect the heart, which include coronary artery disease, heart failure, valvular heart disease, and congenital heart defects. Several factors can potentially contribute to the development of heart disease, including genetics, lifestyle choices, and certain medical conditions.

Symptoms of heart disease can vary depending on the specific condition. However, some common symptoms that may be experienced include chest pain, shortness of breath, palpitations, dizziness, and fatigue. If you are experiencing any of these symptoms, it is important to see a doctor as soon as possible so that the cause can be properly diagnosed and treated."

Probst adds, "One preventive measure of heart disease that is often overlooked is annual blood testing. Annual blood testing is important because it can detect the problem well in advance of symptoms, so you can correct the problem before it becomes a serious disease.  Unfortunately, the blood tests that many physicians order are insufficient for identifying the heart disease risk markers that you need for healthy aging and longevity.  The good news is that you can manage some of your annual blood testing on your own at a very reasonable price.  You can purchase the blood tests online or over the phone. You will be mailed a doctor's order to have your blood drawn at a local lab.  When you get the test results, you should take them to your doctor to discuss them and have them added to your health records."


Pancreatic Cancer


Shubham Pant, M.D., associate professor of Gastrointestinal Medical Oncology at The University of Texas MD Anderson Cancer Center explains, "Pancreatic cancer is the third leading cause of cancer mortality in the United States, causing an estimated 47,050 deaths in the year 2020. The reason for the poor prognosis is that a majority of patients with pancreatic cancer present with Stage 4 disease. Risk factors include cigarette smoking, obesity and chronic pancreatitis (inflammation of the pancreas). The risks can be reduced by quitting smoking and losing weight (if obese). 

Dr. Pants adds, "There is no screening test for pancreatic cancer, and unfortunately it is mostly diagnosed when it has already spread to other organs, but the treatments are improving over the last decade. A number of targeted therapies have been approved for treating pancreatic cancer. The survival is better in the earlier stages of the disease (Stage 1-3) than if diagnosed at Stage 4. Though traditionally the outcome has been poor for pancreatic cancer, with new tests, like next generation sequencing, we can identify a subset of patients with pancreatic cancer who have an improved survival."

Pancreatic cancer is rarely detected early and according to the Mayo Clinic, "Signs and symptoms of pancreatic cancer often don't occur until the disease is advanced. They may include:

  • Abdominal pain that radiates to your back
  • Loss of appetite or unintended weight loss
  • Yellowing of your skin and the whites of your eyes (jaundice)
  • Light-colored stools
  • Dark-colored urine
  • Itchy skin
  • New diagnosis of diabetes or existing diabetes that's becoming more difficult to control
  • Blood clots
  • Fatigue"
Heather Newgen
Heather Newgen has two decades of experience reporting and writing about health, fitness, entertainment and travel. Heather currently freelances for several publications. Read more about Heather
Filed Under