You’ve probably heard age-old sayings like “breakfast is the most important meal of the day” or “sugar is bad for your health.” But are these claims rooted in science?
When parents, friends, and even traditions, pass down misconceptions and outdated beliefs, it’s easy to skip over questioning their validity. Sometimes we can tell these old wives' tales aren't true even without the research to back them up. Like "chewing gum will stay in your stomach for seven years if you swallow it" or "you can drown if you swim after eating."
But when it comes to some health myths, there's more at stake. Following incorrect health advice can be dangerous, so we decided to get to the bottom of these myths once and for all.
We asked our Nutrition Team to help us debunk 14 popular nutrition and lifestyle myths. Here's what our nutritionists—and the research—say about these myths.
1) Skipping Breakfast is Bad for You
“Breakfast is the most important meal of the day” is an expression you’ve probably heard relentlessly since childhood. But some studies have indicated that this may not necessarily be true.
In individuals with diabetes, not eating breakfast was associated with more significant glucose spikes after eating.
However, practices like intermittent fasting show that it may be possible to lose weight, decrease cholesterol levels, and more while following an alternate-day fasting plan.
Other studies state that while eating breakfast may appear to be associated with a reduced risk of obesity and other health conditions, it’s impossible to attribute these health effects to eating breakfast alone.
Starting your day with a low-quality meal appears to have more negative effects on health than skipping breakfast. This means that the quality of the breakfast meal and how nutrient-dense it is might be what is most important.
2) All Carbs Are Bad for You
In diet culture, carbohydrates are often the villains, especially for people with obesity. But as with all things diet culture, you may be better off ignoring that.
Carbohydrates can be divided into two main categories: simple and complex carbs.
1) Simple Carbohydrates
These tend to be high in sugar, highly processed, and include foods such as candy, sugary drinks, and baked goods.
While evidence suggests that we should limit simple and refined carbs as they contain little nutritional value, complex carbs are a different story.
2) Complex Carbohydrates
These are higher in fiber and slow to digest. They're in items such as legumes, whole grains, and potatoes.
Many carbohydrates are essential sources of energy and fiber for our bodies and complex carbohydrate sources such as beans contain many vital nutrients.
These carbohydrates are an essential component of a balanced diet for many. They tend to have a lower glycemic index which may help blunt glucose spikes, support healthy cholesterol levels, and promote gut and heart health.
All this to say, while you should limit some types of carbohydrates in a nutritious diet, prioritizing nutrient-rich carbs can be highly beneficial for your health.
3) Fruits Are Bad for People with Diabetes
Fruits are a delicious source of important vitamins and minerals essential for our health, but what about their high sugar content?
Because many fruits tend to be high in sugar, some people falsely believe that eating fruit can contribute to diabetes or worsen the condition. However, the sugar content in fresh fruit occurs naturally, which is quite different from added sugars.
In fact, according to the American Diabetes Association, most individuals with diabetes can include fruit as part of a safe and healthy diet. Choosing fruits with a low glycemic index or pairing fruit with a source of protein, such as plain Greek yogurt, may help if you're concerned about sugar intake.
However, as long as you control your portion sizes and eat mindfully, eating fruit is perfectly healthy for most individuals with diabetes.
4) Eggs Increase Cholesterol Levels
Research previously believed that eating high cholesterol foods such as eggs contributed to high cholesterol levels in the body.
However, new research has debunked this myth, shifting the focus to a combination of things. Other factors now being studied include physical activity levels and consumption of excess carbs, saturated fats, and trans fats.
One study by Harvard researchers linked diets containing one egg per day is not associated with an increased risk for cardiovascular disease lowering cholesterol levels in healthy individuals.
As other items such as highly processed and fried foods are observed to negatively affect cholesterol, limiting these items and prioritizing fiber, unsaturated fats, and physical activity can support healthy cholesterol levels.
5) Sweet Potatoes Will Always Spike Your Glucose
Sweet potatoes are typically considered a healthy option due to their high vitamin A content and antioxidants. Still, people with diabetes may wonder if they’re safe to eat without causing blood sugar spikes.
While it’s true that sweet potatoes are high in carbohydrates, they also contain fiber that can help balance out glucose levels.
Some of the confusion around sweet potatoes may lie around their glycemic index, which can vary depending on their cooking method. Boiling sweet potatoes helps keep the resistant starches intact and lower their glycemic index, slowing digestion and regulating glucose levels.
Do sweet potatoes sometimes cause glucose to spike? Sure! But this doesn't mean they always will.
Boiling potatoes, cooking them and then letting them cool off, or even pairing them with a protein are a few easy ways to help blunt potential spikes. However, remember that people respond differently to certain foods, so it’s essential to determine what works best for you. An excellent way to find out is to use a tool like a continuous glucose monitor.
6) Women Get Bulky by Lifting Weights
Many women avoid lifting weights at the gym due to an outdated belief that weight lifting can make their bodies too bulky or muscular.
However, as anyone who may have intentionally tried to put on muscle will know, bulking up is not an easy feat.
It’s essential for women to consider these findings since weight training has other health benefits that go beyond aesthetics. Lifting weights is a highly beneficial way to burn calories, stay in shape, improve blood sugar control, and can help you to stay active for longer in life.
Some professionals recommend regular weight training over cardio exercise for fat loss, which may drive similar results.
So, the next time someone tries to convince you that lifting weights will make you bulkier or heavier, remind them that resistance training may help lower body fat percentage.
7) Adrenal Cocktails Help with Hormonal Balance
Adrenal fatigue, which can also be described as hypothalamic-pituitary adrenal axis dysfunction, is a condition where the adrenal gland can become overworked and stop producing hormones. However, adrenal fatigue itself has not been scientifically proven to exist, and research is still ongoing here.
But that hasn't stopped the promising effects of adrenal cocktails from making this drink popular.
Adrenal cocktails are typically made with ingredients like coconut water, aloe vera juice, and orange juice, among other things. The drink is intended to supply the body with sodium, vitamin C, and potassium.
It's always best to consult your doctor before trying anything new like this, especially if you experience low energy levels, trouble sleeping, weakness, or loss of appetite after drinking it.
8) Gluten-Free Foods are Healthier for Everyone
Another nutrition trend is the gluten-free diet. Gluten is a protein found in wheat and appears in everyday items such as bread, pasta, beer, and some sauces.
People with Celiac disease avoid consuming gluten as it causes painful damage to their small intestine. However, only one percent of the global population is thought to suffer from this condition. It’s also possible to be gluten intolerant without having Celiac disease, in which case limiting gluten products is necessary.
However, for people with no known history of gluten sensitivity, limiting gluten has not been observed to have any additional scientifically proven benefits.
In fact, gluten-free diets can increase nutritional deficiencies in people without gluten intolerance. You may instead be unintentionally cutting things like fiber, vitamin B, iron, zinc, and potassium out of your diet.
Other studies suggest limiting gluten without cause can have adverse effects like hyperglycemia and coronary artery disease.
Speak with a medical professional before making significant dietary changes to determine what’s right for you.
9) Everyone Should Take Probiotics Daily
Probiotics are well known to support gut health and boost the immune system, but should you really take them every day?
According to Harvard researchers, probiotics can be beneficial, but it can be challenging for consumers to determine the quality of their probiotics as the FDA does not regulate these supplements.
Other research shows that in many cases, scientists don’t have enough evidence to determine which types of probiotics can positively affect certain conditions. We also don't know the length of time you should take them to get the best results.
More research is needed to determine probiotics' safety and potential risks, especially for the elderly or immunocompromised.
10) Cracking Your Knuckles Causes Arthritis
Cracking your knuckles may be something you were scolded for as a child, and some even hold onto the belief that doing this could lead to arthritis later in life.
However, research on this habit has largely determined that cracking your knuckles is mostly harmless.
Other studies have indicated that this habit may lead to temporary swelling and decreased grip strength.
Fortunately for many of us, there's no scientific evidence found that links knuckle cracking to arthritis.
11) Coffee Stunts Your Growth
If you were someone who was not allowed to drink coffee or other caffeinated beverages as a child, this one will disappoint you. There's no evidence to support this myth!
Coffee and caffeine, in general, have not been observed to affect height or development. Instead, other factors determine your height, including genetics, dietary factors (such as getting enough calcium), and sleep.
This myth may arise from research that found a possible link between caffeine consumption during pregnancy and miscarriages. There have been no studies to suggest that coffee has any significant effects on the development of young children.
12) Cutting Out all Sugar Keeps you Healthy
Sugar is another villainized dietary element, sometimes for a good reason. Research has found that American adults consume three times the recommended daily sugar intake, which is concerning in and of itself.
However, completely cutting out sugar is not only extremely difficult but also not typically recommended as part of a balanced diet.
Sugar plays a vital role in providing the body with energy. Rather than eliminating it, aim to limit foods with added sugars and little nutritional value and focus on consuming whole foods.
Many natural sugars are in vitamin and nutrient-rich foods like fruits and vegetables. Research also suggests that natural sugars do not share any adverse effects of added sugars in items such as fruit juice and other sugary drinks.
However, consuming added sugars in excess has been linked to obesity, cardiovascular disease, type 2 diabetes, and even some cancers. Instead, consume the recommended daily intake of sugar (less than 10 percent of daily calories) and eat sweets in moderation.
13) Sitting is the New Smoking
“Sitting is the new smoking” is a claim that has been around for about a decade, and it’s not without merit. Research has shown that sitting for extended periods can lead to obesity, cancer, metabolic syndrome, and heart disease.
While this research is vital to consider, some scientists have countered this argument with the assertion that the act of sitting itself may not necessarily be the root cause of these health conditions.
Instead, a lack of physical activity may be behind some adverse health effects of a sedentary lifestyle.
When you find yourself sitting for eight hours a day at the office, it can be hard to find time to exercise. Prioritize movement in any way you can. If you work from home, get a standing desk and take five-minute breaks every hour to stretch your legs.
If you commute to work, try walking or biking (or parking farther away if work is too far!) to help combat the effects of too much sitting.
14) Red Meat is Bad For You
Red meat came under fire after studies found that there may be a link between eating red meat and an increased risk for heart disease, cancer, and diabetes.
While these findings sound alarming, most research suggests that the effects may come from extremely high consumption. Other research suggests that processed meats have a higher association with developing certain cancers.
Regular portions (two to three servings per week for some, but others may benefit from less or more) may lower the risk of these health conditions.
Meat is a highly nutritious food that you can include in a healthy, balanced diet. While researchers continue to study potential adverse health effects, remember that everyone's diet is different!
If some of these myths surprised you, we hope we’ve helped debunk them with science-based evidence. Here are two takeaways to keep in mind as you navigate through misinformation and false claims.
Do Your Research
Did you hear through the grapevine that something was good or bad for you? Doing your own research is essential, especially with things that affect your health and wellbeing.
Also, seek nutrition and other health-related advice from a credentialed medical professional who can help you better understand your individual health needs.
You might have noticed a trend among many of these myths, and that is the fact that they support extreme dietary limitations.
However, some studies suggest that for most people, limiting entire food groups may not be necessary or ideal in most cases. Consulting with your doctor is the best way to determine what’s best for your specific needs.
Engage with Your Blood Glucose Levels with Nutrisense
Your blood sugar levels can significantly impact how your body feels and functions. That’s why stable blood glucose levels can be an important factor in supporting overall wellbeing.
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With over 11 years of experience as a dietitian in many areas of nutrition, Katie has worked as a clinical dietitian within a hospital, as well as in the fields of diabetes, sports and performance nutrition, recovery from addiction, and general wellness. She’s also an athlete and has run 8 marathons, including the Boston Marathon.