Some health myths might make your skin crawl, like the idea that cracking your knuckles will give you arthritis, going outside with wet hair will make you sick, or—mom’s favorite—crossing your eyes for too long will leave them stuck that way.
Sometimes the scariest health beliefs aren’t the truly outrageous ones, but the myths that sound plausible enough that they just might work. The most concerning part is how they stick around even when research debunks them, leading you astray on your health journey.
And that’s truly frightening. This article will examine seven hair-raising common health myths that are repeated year-after-year—let’s just call them the skeletons in your (health) closet. Keep reading to learn more about health myths vs. facts, and how letting go of this lingering folklore means you can focus on what really matters.
Myth #1: If your bloodwork is normal, everything must be fine
Your blood reveals a lot about the inside workings of your body, including cardiometabolic health, kidney disease, and more. More extensive panels may assess additional biomarkers, offering information about different aspects of how your body is functioning.
That said, blood biomarkers, like any type of testing, isn’t a complete profile of your health. Blood panels provide one type of health information, but these tests can't possibly evaluate every possible condition or structural change in the body.
That's why being on top of your health care involves more than a single test. Things like regular appointments with your primary care provider, annual skin checks with a dermatologist, and recommended screenings based on your age, medical history and individual risk factors all serve important purposes.
Supplemental imaging, such as Prenuvo's Whole Body Scan, can also be helpful. It provides even more information by giving you and your doctor a birds-eye-view of your health, screening for over 500 conditions across your entire body, including 65 organs.
Related: You may not be the same person you were last year
Myth #2: A normal BMI means you’re healthy
Nearly 7% of adults who are underweight or normal weight have diabetes. About 20% of people with a normal weight have fatty liver (metabolic dysfunction-associated steatotic liver disease). The point is: It’s possible to have a chronic disease at any weight.
Body Mass Index (BMI) is a screening tool that uses a person's height and weight to estimate body fat and assess general weight categories. While a starting point, BMI is quite limited as a health metric. It cannot tell you how much muscle or fat you have, or where that fat is stored and how much visceral fat (which surrounds internal organs and is associated with metabolic and cardiovascular health risks) is living inside your abdomen.
Recent research suggests BMI alone may underestimate obesity when compared with assessments that measure body fat directly. One study reported that approximately one-quarter of adults classified as having a normal BMI and about half of those classified as overweight met the study's criteria for obesity based on body fat. Another study found that roughly one in five people with a normal BMI had an elevated waist-to-hip ratio, a measure of abdominal fat distribution associated with cardiovascular risk.
Related: New study links waist size to heart risk, even with a “normal” BMI
Rather than placing all your eggs in the BMI-basket, leaning on multiple measures of body weight and body composition can provide more accurate information about visceral fat and muscle mass, two important markers for disease risk and longevity. Along with weight, waist circumference, and BMI, Body Composition Analysis is a helpful way to track where you are now—and your progress in the future.
Myth #3: You can catch up on sleep later
If there’s one thing people are good at, it’s sacrificing sleep now and banking on the weekend to play catch up. It’s reported that one-third of U.S. adults get less than the recommended minimum of 7 hours of sleep per night.
But experts recommend consistently getting adequate sleep, both for better brain performance and health. The reason? Research shows the consequences of sleep deprivation are vast: hypertension, stroke, coronary heart disease, obesity, type 2 diabetes, anxiety, emotional regulation problems, stress resilience issues, and depression.
One bad night is okay. That concert or dinner you stayed out late for? Worth it. But over time, sleep deprivation can catch up with you. The best thing you can do is maintain a regular sleep-wake up schedule, since inconsistency is linked to reduced cognitive performance, mental health, metabolic health, and higher mortality risk.
Catch-up sleep can be beneficial, but it has its limits. A panel of sleep experts define this as one to two hours of extended sleep or naps on non-work days, but they note that it cannot fully fix the sleep deficiency that occurs from lost sleep. Setting a bedtime alarm is one helpful trick to remind you to start your nightly routine and have lights out—and no phone—on a consistent schedule.
Myth #4: A detox can “cleanse” your body
Your liver, kidneys, and digestive tract are responsible for detoxifying your body and removing waste. Your liver does much of the detox work, metabolizing substances like alcohol and medications and sending them to be excreted from the body. Your kidneys also filter your blood and excrete waste from your body. And your large intestine turns food into waste so you can excrete that, too.
These organs are all very complex systems that don’t need help from detox cleanses, teas, supplements, or restrictive diets. Products aimed for detoxification or weight loss can be harmful, too, causing electrolyte imbalances, heart problems, and liver injury—even in healthy people. Supporting your body’s natural detox processes means taking care of your liver and kidneys with regular exercise, a balanced diet, hydration (water), avoiding smoking and alcohol, and keeping your blood pressure and cholesterol in check.
Bloodwork can also provide information about liver and kidney health. For example, Prenuvo's blood panels include biomarkers such as ALT and AST, which can indicate liver injury, and creatinine, which helps assess kidney function. These results can provide useful information to discuss with your healthcare provider, although bloodwork alone cannot rule out every liver or kidney condition.
Related: The liver does far more than “detox” your body
Myth #5: Heart disease is mostly a men’s health issue
In movies and TV shows, the person who grips their chest with a heart attack and falls to the floor is often a male. But this discounts the fact that heart disease is the number one killer of both men and women, causing the death of one person every 34 seconds.
The reality is that women have specific risk factors that make them prone to heart disease, such as hypertension or gestational diabetes in pregnancy, autoimmune disorders, and depression and anxiety. And while the most common heart attack symptom is the same for men and women—chest pain—women also experience under-the-radar symptoms like anxiety, shortness of breath, upset stomach, pain in the shoulder, back, or arm, or unusual tiredness or weakness, all of which can be mistaken for something else.
Heart disease and the risk factors are not always obvious; high blood pressure is a silent condition and plaque builds up in arteries over time. You need to understand your individual cardiovascular risk factors. That can be done through blood testing for lipids, blood pressure checks, and an EKG and coronary artery calcium tests (if doctor-recommended). Prenuvo’s Advanced Heart Health Scan, can be a helpful addition (not replacement) in your heart health lineup. It uses MyoStrain® analysis to measure heart muscle strain, providing information on how the heart moves with each beat and giving you something you can measure against each time you get another scan.
Myth #6: Cancer always comes with symptoms
Many cancers develop without noticeable symptoms, particularly during their early stages. This is one reason why guideline-recommended screenings, such as mammograms and colorectal cancer screenings, are recommended at certain ages and intervals. They can help identify certain cancers or precancerous changes before symptoms develop, when treatment may be more successful.
The importance of early detection is reflected in decades of cancer research. According to the American Cancer Society's 2026 cancer statistics, the five-year relative survival rate for all cancers combined increased from 49% in the mid-1970s to 70% for people diagnosed between 2015 and 2021. Advances in treatment and earlier detection have contributed to progress, although outcomes vary by cancer type and population. The World Health Organization's 2026 Global status report on cancer also emphasizes the importance of prevention, early detection and access to quality cancer care.
Not every cancer can be detected early, and no screening can eliminate cancer risk. Whole body MRI does not replace guideline-recommended cancer screenings, such as mammography or colonoscopy. It can provide complementary information about certain structural abnormalities, including findings that may warrant further evaluation.
Myth #7: If you feel healthy, you are healthy
Feeling good is important, but just because you don’t have any complaints right now doesn’t mean that all is 100% in your body.
Some health conditions can develop without obvious symptoms until they’re advanced. Many diseases are dubbed “silent diseases,” such as fatty liver (even if you don’t drink), hypertension, prediabetes, among others. Other chronic diseases develop over time, changing your health so slowly that they go undetected.
Related: 12 hidden conditions a whole body MRI can help detect before symptoms start
Preventative health care with your doctor is the first step in checking in on your health, but there’s more that you can do to go beyond the traditional touch-points. At Prenuvo, our offerings are designed to support a deeper look at different aspects of your health—from structural changes in the body, to key biomarkers in your blood, to detailed insights on your muscle and fat distribution.
The healthiest habit might be questioning what you “know”
Medical myths have a way of capturing our attention because we have good intentions when we follow them, whether that’s a detox or thinking everything is fine if we don’t have symptoms. The truth is that health science evolves over time. Often, familiar advice gets repeated over and over until it’s engrained in our brains and we collectively believe it.
Relying on credible evidence, recommended preventive care, and conversations with your healthcare providers brings you to a point of nuanced, individualized care—not health rules that rely on shaky claims.
While we can consider these health myths debunked, you’ll want to know where to go from here. If you’re developing a proactive health approach, consider the tools available to you that can complement, not replace, our regular medical care and guideline-recommended screening.
To learn more about a Prenuvo Membership or standalone services, book a call with our Patient Services Team.
