"Breakfast is the most important meal — it boosts metabolism and helps you lose weight."

🔴 Myth (as a weight-loss hack)

Pooling the randomized trials, people told to eat breakfast actually took in ~260 more calories a day and weighed slightly more, not less. Eat it if you like it — just don't expect it to burn fat.

📋 Systematic review + meta-analysis · 13 RCTs — Sievert et al., BMJ 2019 · read the study → · permalink →

"Sugar makes kids hyperactive."

🔴 Myth

Across 23 blinded studies — where no one knew who got sugar vs. a sweetener — sugar had no effect on kids' behavior or attention. It's the party, not the cake.

📋 Meta-analysis · 23 studies — Wolraich et al., JAMA 1995 · read the study → · permalink →

"MSG gives you headaches."

🔴 Myth

When MSG is properly hidden in food and blinded, the "MSG headache" mostly vanishes. The scare traces back to weak, unblinded studies — and MSG occurs naturally in tomatoes and parmesan.

📋 Systematic review of human studies — Obayashi & Nagamura, J Headache Pain 2016 · read the study → · permalink →

"Vitamin C prevents colds."

🔴 Myth (for most of us)

In 29 trials of 11,000+ people, taking vitamin C daily did not lower your odds of catching a cold (it trims a little off how long one lasts). The exception: people under extreme physical stress, like marathon runners.

📋 Cochrane meta-analysis · 29 trials, 11,306 people — Hemilä & Chalker, 2013 · read the study → · permalink →

"A daily multivitamin keeps you healthy."

🔴 Myth (mostly)

In 84 studies of 740,000 people, vitamin/mineral supplements did little or nothing to prevent heart disease, cancer, or early death in well-nourished adults — and beta-carotene raised lung-cancer risk in smokers. Real food still wins.

📋 Systematic review for the USPSTF · 84 studies, 739,803 people — O'Connor et al., JAMA 2022 · read the study → · permalink →

"Antioxidant supplements help you live longer."

🔴 Myth

Across 67 trials of 230,000+ people, antioxidant pills didn't extend life — and beta-carotene, vitamin A and vitamin E were linked to slightly higher mortality. Get your antioxidants from food, not a bottle.

📋 Cochrane meta-analysis · 67 RCTs, 232,550 people — Bjelakovic et al., 2008 · read the study → · permalink →

"Fish-oil (omega-3) supplements protect your heart."

🔴 Myth (for supplements)

The largest review — 86 trials, 160,000+ people — found omega-3 supplements have little or no effect on heart attacks, strokes, or dying. (They do lower triglycerides, and eating actual fish is a different question.)

📋 Cochrane meta-analysis · 86 RCTs, 162,796 people — Abdelhamid et al., 2020 · read the study → · permalink →

"Calcium and vitamin D pills prevent broken bones."

🔴 Myth (for most older adults)

Across 33 trials of 51,000 older adults living at home, calcium and/or vitamin D supplements did not lower the risk of hip or other fractures. (It's a different story if you're truly deficient or in a care facility.)

📋 Systematic review + meta-analysis · 33 RCTs, 51,145 people — Zhao et al., JAMA 2017 · read the study → · permalink →

"Glucosamine and chondroitin fix joint pain."

🔴 Myth

Pooling the trials, glucosamine/chondroitin didn't beat placebo for joint pain or slow the arthritis — and the independent, non-industry studies showed the smallest effects of all.

📋 Network meta-analysis · 10 trials, 3,803 patients — Wandel et al., BMJ 2010 · read the study → · permalink →

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