From IMH:

In the age of social media and 24 hours news cycles, we are all subject to nutrition misinformation. As Registered Dietitians, we hear well-intentioned but misleading nutrition beliefs from patients and families on a regular basis.

In honor of National Nutrition Month, an annual education campaign from the Academy of Nutrition and Dietetics, we wanted to break down five of the most common myths that we hear.

Myth #1
​“Seed Oils Cause Inflammation”

Seed oils — like soybean, sunflower, safflower, corn, and canola oil — are often blamed for everything from chronic inflammation to obesity. The argument usually centers around omega‑6 fatty acids, specifically linoleic acid. The story goes like this:

• Omega‑6 → inflammation → chronic disease.
• Simple. Neat. Viral on Instagram.
• But not supported by human evidence.

Large systematic reviews and controlled trials consistently show that linoleic acid intake does not increase inflammatory markers in humans and is often associated with better cardiometabolic outcomes. For example, a recent systematic review examining seed oils and metabolic health found improvements in lipid profiles and oxidative stress markers in many studies. (PMID: 39996006)

Even more importantly, replacing saturated fat with polyunsaturated fats — like those found in seed oils — consistently reduces LDL cholesterol and cardiovascular disease risk. So why do people feel better when they remove seed oils? Usually because they also removed foods like:

• fast food.
• fried takeout.
• packaged snack foods.
• ultra-processed desserts.

In other words, the improvement usually comes from eating fewer ultra-processed foods, not from removing the oil itself..

The Real Takeaway

Seed oils aren’t magic health foods — but they’re also not inflammatory toxins. They’re simply unsaturated fats that can fit into a balanced dietary pattern

Myth #2
​“Fructose in Fruit Causes or Worsens Metabolic Disease”

This myth usually starts with a true statement: Fructose can contribute to metabolic problems in high amounts. But the leap people make is assuming fruit behaves the same way as added sugars. It doesn’t. Fruit is not just fructose! Whole fruit contains:

• fiber.
• water.
• vitamins and minerals.
• polyphenols.
• low energy density.

All of these factors influence how the body metabolizes sugar. This concept is known as the food matrix – the structure and combination of nutrients in a whole food that changes how it affects the body.

When researchers look at real dietary patterns, the findings are remarkably consistent. Large meta-analyses consistently show that higher fruit intake is associated with lower risk of Type II Diabetes. For example:

• A meta-analysis of over 400,000 participants found that greater fruit consumption was associated with reduced diabetes risk. (PMID: 25074631)
• Another meta-analysis of cohort studies found a 7% lower diabetes risk among people who consumed more fruit. (PMID: 25377009)
• And when researchers examine fructose-containing foods separately, fruit intake is generally neutral or protective, while sugary beverages increase risk. (PMID: 32644139)

In contrast, sugar-sweetened beverages consistently show increased diabetes risk. 

The difference? Liquid sugars deliver large amounts of rapidly absorbed sugar without fiber or satiety. Fruit does the opposite.

What Really Matters

Even in people with diabetes, research suggests whole fruit may improve glycemic markers like HbA1c and fasting glucose in some contexts.

Myth #3
​“You Need 1 Gram of Protein Per Pound of Body Weight”

If you’ve spent more than five minutes on TikTok or Instagram, you’ve probably heard this one: ​“It is best to consume 1 gram of protein per pound of body weight every day.” For many people, that would mean eating protein like it’s a full-time job.

Here’s the reality: for most healthy adults, protein needs are much lower than what social media suggests. The current Recommended Dietary Allowance (RDA) established by the National Academy of Medicine is 0.8 grams of protein per kilogram of body weight per day (about 0.36 g per pound). That amount is designed to meet the needs of the majority of healthy adults.

Now, there are situations where people benefit from higher protein intake — such as athletes, people trying to preserve lean body mass during weight loss, older adults, or individuals recovering from illness. In these cases, many experts in sports and clinical nutrition recommend something closer to 1.2 – 2.0 g/​kg/​day. Even at the high end of that range, most people still fall well below the ​“1 gram per pound” rule that’s often thrown around online.

For example:

A 160-lb adult needs roughly 60 – 100 grams of protein per day depending on activity level and health goals—not 160 grams.

And the good news? Most Americans already meet or exceed their protein needs without trying very hard!

Bottom Line

Protein is important, but more isn’t always better. Focus on including a source of protein at meals, pairing it with fiber-rich foods like whole grains, fruits, and vegetables, and let the influencers keep their pureed cottage cheese and egg white protein shakes.

Myth #4
​“This Powder/​Capsule/​Injection/​Peptide Will Fix Everything”

If wellness influencers are to be believed, every capsule, powder, gummy, and neon-colored drink mix will help you:

• Burn fat.
• Build muscle.
• Fix your gut.
• Boost your brain.
• Improve sleep.
• And possibly achieve enlightenment.

But here’s the inconvenient truth: dietary supplements are not regulated like medications.

In the United States, supplements fall under the Dietary Supplement Health and Education Act (DSHEA) of 1994, overseen by the U.S. Food and Drug Administration. Unlike prescription drugs, supplements do not need to prove they are safe or effective before they are sold. Companies are largely responsible for ensuring their own products are safe and accurately labeled.

That means a supplement can be marketed online with bold claims, flashy packaging, and thousands of likes — but that doesn’t mean it’s effective, necessary, or even contains what the label says.

This doesn’t mean all supplements are bad. In fact, some supplements can be very helpful when used appropriately, such as:

• Vitamin D for individuals with deficiency (or who live in Wyoming).
• Iron when medically indicated.
• Vitamin B12 for certain diets or absorption issues.
• Prenatal vitamins during pregnancy.

When supplements are needed, we recommend choosing products that have been independently tested for quality and purity by organizations such as:

• U.S. Pharmacopeia.
• NSF International.
• ConsumerLab.

These third-party certifications help verify that the product contains what it says it contains — and nothing it shouldn’t.

RDN Reality Check

If a supplement sounds too good to be true, it probably is. Before spending money on the latest social-media ​“miracle,” talk with a registered dietitian (like us!!) or healthcare provider who can help determine whether a supplement is necessary, safe, and evidence-based.

Myth #5
​“Sugar Feeds Cancer”

This is a common concern that we hear from patients with cancer that can lead to food fears and restriction during the treatment process. 

When we eat carbohydrate containing foods, our bodies digest, absorb and ultimately metabolize them into glucose. Glucose is a simple form of sugar that fuels every cell in our body, including cancer cells. 

The truth is though, eliminating sugar does not ​“starve” cancer cells. Our bodies regulate glucose levels to keep our cells fueled, even if someone stops eating carbohydrates. This often happens by turning proteins into glucose.

Let’s Clear It Up

While eating sugar does not directly result in tumor growth, dietary patterns such as high intake of ultra-processed foods have been linked with increased risk of certain cancers. So, when we talk to cancer patients about nutrition, we focus on overall healthy dietary habits and eating enough during treatment to stay strong, rather than cutting out large food groups. 

Bottom Line: Nutrition advice online can be entertaining — but it’s not always accurate. When in doubt, trust the professionals who spend their careers studying nutrition science. (Hint: that would be your friendly neighborhood Registered Dietitians Rae, Meaghan, and Stephanie.)