Why ditching outdated nutrition dogma could save your health, performance, and longevity.
You’re not wrong if you feel like nutrition advice changes with the wind. Eggs are good. Eggs are bad. Fat makes you fat. No, carbs make you fat. Salt will kill you. Wait, maybe salt saves you.
Much of what we’ve been told was oversimplified—or flat-out wrong. As evidence mounts, many trusted voices in longevity and health — Peter Attia, Chris Masterjohn, Rhonda Patrick, Layne Norton, and the late Ray Peat — have challenged outdated FDA-era recommendations. More often than not, they’ve been proven right as the evidence base grows.
This article examines six of the biggest nutrition myths still in existence. Not only are they misleading, but adhering to them can actually do more harm than good.
1. “Salt Is Bad for You”
The Myth: All salt raises blood pressure and causes heart disease.
The Reality: Sodium is essential. The real issue is electrolyte imbalance.
Trace Minerals and Balance
Not all salt is created equal. Sea salt and mineral-rich salts like Celtic Sea Salt contain trace elements — magnesium, potassium, calcium — that play crucial roles in hydration, nerve signaling, and muscle function. Sodium itself isn’t the problem; imbalance is. Blood pressure can indeed climb when sodium intake is high and potassium is low (as is common in processed food diets).
The Benefits of Iodine
Let’s not forget iodine, often added to table salt as a public health measure against goiter and thyroid dysfunction. Inadequate iodine intake can wreck hormonal balance, slow metabolism, and impair cognitive function. Eliminating salt without replacing iodine is a fast track to deficiency.
Who Should Actually Limit Sodium?
Yes, some people with salt-sensitive hypertension, kidney disease, or certain genetic predispositions should limit sodium. But for the average healthy person, the “2,300 mg/day or else” mantra is unnecessarily restrictive.
The Drawbacks of Too Little Sodium
Low sodium intake can backfire. Studies show that restricting sodium too aggressively raises renin and aldosterone, hormones linked to cardiovascular stress. Athletes and active individuals who lose sodium through sweat may experience fatigue, muscle cramps, and even hyponatremia (dangerously low sodium) if they under-consume salt.
Bottom line: Salt isn’t the enemy. Poor diet quality and electrolyte imbalance are.
2. “A Vegan Diet Is Automatically Healthier Than Eating Meat”
The moral and environmental arguments for veganism aside, the claim that it’s universally “healthier” than omnivorous eating doesn’t hold up under scrutiny.
The China Study and Its Flaws
Much of the vegan health halo comes from The China Study, a massive epidemiological project linking animal protein to chronic disease. The problem? Correlation isn’t causation. The data was cherry-picked, confounding factors weren’t fully accounted for, and follow-up analyses have dismantled many of its conclusions.
Quality Protein Matters
Not all meat is created equal. A grass-fed steak or pastured eggs provide bioavailable amino acids, omega-3 fatty acids, and micronutrients that are hard to replace. Contrast that with hot dogs, fried chicken, or deli meat, and it’s no wonder meat sometimes gets lumped into the “unhealthy” bucket.
Protein’s Role in Longevity
Protein is essential for detoxification (via liver enzymes), immune system repair, and maintaining muscle mass — arguably one of the best predictors of longevity. Sarcopenia (age-related muscle loss) is a serious risk factor for frailty and mortality. Adequate protein intake, especially from high-quality sources, is protective.
Nutrient Gaps in Long-Term Veganism
Long-term vegan diets often fall short in vitamin B12, heme iron, zinc, taurine, creatine, DHA, and complete proteins. These aren’t trivial — deficiencies can impair brain health, energy, and cause muscle loss. Comprehensive nutritional supplement regimens can help, but they underscore that “plant-only” isn’t inherently superior.
Bottom line: A well-planned omnivorous diet with quality protein sources often outperforms veganism in nutrient sufficiency and long-term vitality.
3. “Eating Cholesterol Raises Cholesterol”
The Myth: Egg yolks clog your arteries.
The Reality: Dietary cholesterol barely affects blood cholesterol in most people.
Cholesterol’s Role in Hormones & Health
Cholesterol is required to synthesize steroid hormones (testosterone, estrogen, cortisol), vitamin D, and bile acids. Removing dietary cholesterol sources can impose stress via de novo synthesis, which has energetic costs.
Ray Peat emphasized that suppressing cholesterol too aggressively — whether through diet or with statins — can impair thyroid and steroid hormone production, reduce resilience, and even affect brain function, since cholesterol is a critical structural component of neurons and synapses.
Statins and Downstream Risks
While statins lower LDL cholesterol, they can also blunt CoQ10 synthesis, potentially affecting energy production. They’re lifesaving for some populations, but they’re not without trade-offs.
The Evidence Problem
Most studies now show that eating cholesterol-rich foods (like eggs) doesn’t significantly impact long-term blood cholesterol levels in most people. The body regulates its own cholesterol production, dialing it up or down depending on intake.
HDL vs LDL
The simplistic “high cholesterol = bad” model misses nuance. LDL particles vary in size and density — small, dense LDL is more atherogenic than large, fluffy LDL. HDL (“good cholesterol”) helps clear excess cholesterol. Context matters far more than total numbers.
Bottom line: Cholesterol in food isn’t the villain — it’s one part of a complex system that supports hormone balance, energy, and resilience.
4. “Gluten-Free Only Benefits Those With Celiac”
The Myth: Only people with celiac disease benefit from avoiding gluten.
The Reality: Gluten sensitivity exists on a spectrum.
• Gluten can increase gut permeability (“leaky gut”) even in some non-celiac individuals, contributing to systemic inflammation.
• Symptoms may include brain fog, fatigue, joint pain, and bloating.
• No unique health benefit of gluten has been identified. The nutrients commonly credited to gluten-containing grains can be obtained from many other foods.
Bottom line: You don’t need celiac disease to benefit from lowering gluten intake. While not everyone needs to cut it, many feel and function better without it.
5. “Red Meat Causes Cancer”
The Myth: Steak = cancer risk.
The Reality: Context and quality matter.
What Went Wrong
Epidemiological studies linking red meat to cancer often fail to control for confounders. People who eat a lot of processed meat also tend to smoke more, exercise less, and eat fewer vegetables. Is it the steak or the lifestyle?
Quality Over Quantity
Grass-fed, grass-finished beef has a vastly different nutrient profile from feedlot beef. Higher omega-3s, more antioxidants like conjugated linoleic acid (CLA), and fewer inflammatory compounds make it a very different food.
Cooking Methods Matter
Charred, overcooked meat can create heterocyclic amines (HCAs) and polycyclic aromatic hydrocarbons (PAHs), compounds linked to cancer risk. Gentle cooking methods — slow roasting, sous vide, braising — avoid this problem.
Bottom line: Red meat isn’t inherently carcinogenic. Poor quality and poor cooking methods are the real culprits.
6. “IIFYM Means Food Quality Doesn’t Matter”
The Myth: As long as it fits your macros, it’s fine.
The Reality: Calories aren’t the whole story.
Why Quality Counts
- Micronutrients (vitamins, minerals, polyphenols) are critical for cellular health.
- Preservatives, dyes, and emulsifiers disrupt gut bacteria and metabolic signaling.
- Food is information. High-quality food upregulates repair and detox. Junk food scrambles the signals.
Bottom line: IIFYM is useful for calorie awareness, but true health requires looking beyond macros to the quality of what’s on your plate.
Wrapping It Up
Nutrition isn’t about one-size-fits-all rules. It’s about context, nuance, and understanding that food is more than fuel — it’s information that shapes how we age, perform, and thrive.
Demonizing salt, cholesterol, red meat, or protein while elevating veganism, gluten, or ultra-processed foods has left millions confused and, in some cases, harmed. The better path? Embrace nutrient density, context-driven moderation, and an evidence-based openness to evolving research. After all, the goal isn’t just to live longer — it’s to live better. And that requires questioning the myths that no longer serve us.
Practitioners To Know: Why They’re Credible / What They Say
Peter Attia, MD – Focuses on metabolic health, cardiovascular risk beyond lipids (insulin resistance, inflammation), and critiques oversimplified recommendations.
Chris Masterjohn, PhD – Biochemist known for nuanced work on lipid metabolism, vitamins, and nutrient synergy. Emphasizes context in cholesterol and fat intake.
Rhonda Patrick, PhD – Researches micronutrients, inflammation, and aging, highlighting how nutrition impacts longevity pathways.
Layne Norton, PhD – Protein metabolism and body composition expert. Stresses importance of high-quality protein for muscle preservation and metabolic health.
The late Ray Peat, PhD – Biologist remembered for his focus on metabolism, thyroid health, and pro-metabolic nutrition. Advocated for cholesterol’s central role in hormone production and brain health, warned against polyunsaturated fats, and challenged blanket anti-cholesterol messaging.
