17 Things We Thought Were Healthy But Were Actually Harmful
Here's a look at 17 health fads and products once praised for their benefits but later exposed as harmful or deadly.
- Alyana Aguja
- 4 min read
Throughout history, many products and practices were embraced as healthy innovations, only to be revealed later as dangerous. From cigarettes endorsed by doctors to radioactive tonics and sugar-packed “diet” snacks, these trends often caused more harm than good. This list serves as a reminder that health claims should be met with skepticism until proven by solid scientific evidence.
1. Cigarettes as a “Health Aid”
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In the early 20th century, cigarette ads claimed smoking could calm nerves and even aid digestion. Doctors were featured in promotions, reassuring the public that it was safe. Decades later, science revealed smoking’s direct link to lung cancer, heart disease, and countless other health issues.
2. Lead-Based Makeup
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Ancient Egyptians and later European elites used lead-based cosmetics to achieve pale, flawless skin. It was considered a sign of beauty and status. Unfortunately, prolonged exposure caused lead poisoning, neurological problems, and even death.
3. Radioactive Health Products
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In the 1920s, items like “Radithor” were marketed as energy boosters and pain relievers. These products contained radium, which was believed to have revitalizing effects. Instead, users suffered radiation poisoning, bone decay, and fatal cancers.
4. Mercury as Medicine
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For centuries, mercury was prescribed for ailments ranging from syphilis to constipation. Physicians believed it could purge toxins from the body. In reality, it caused severe neurological damage and organ failure.
5. Tapeworm Diet Pills
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In the early 1900s, some people intentionally swallowed pills containing tapeworm eggs to lose weight. The idea was that the parasite would absorb calories from food. Instead, it led to malnutrition, internal organ damage, and life-threatening infections.
6. Asbestos Insulation
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Asbestos was widely used in homes and schools for fireproofing and insulation. It was promoted as safe and durable. Later research found that inhaling its fibers could cause lung cancer, asbestosis, and mesothelioma.
7. Lobotomies for Mental Illness
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Once hailed as a breakthrough treatment for depression, schizophrenia, and anxiety, lobotomies involved surgically severing connections in the brain. While some patients became calmer, many lost personality, memory, and basic functioning. The procedure is now considered barbaric and inhumane.
8. Saccharin Sweetener
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In the 1970s, saccharin was marketed as a healthy alternative to sugar for weight control. Later studies linked high doses in lab animals to bladder cancer. Although still used today in small amounts, its health image has been tarnished.
9. Vibrating Belt Machines
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In the mid-20th century, vibrating belt machines were promoted as effortless fat burners. People believed standing still while a belt jiggled their waist would melt fat away. It did nothing for weight loss and sometimes caused muscle strain.
10. Fen-Phen Diet Pills
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In the 1990s, Fen-Phen became a wildly popular weight-loss drug combination. However, it was later linked to heart valve damage and dangerous pulmonary hypertension. The drug was pulled from the market in 1997 after multiple lawsuits.
11. Shark Cartilage Supplements
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Touted as a cancer cure in the 1990s, shark cartilage was marketed based on the claim that sharks do not get cancer. Scientific studies debunked the idea, showing no cancer-fighting benefit. It also contributed to the overfishing of sharks.
12. Cotton Ear Candling
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Ear candling was advertised as a natural way to remove earwax and toxins from the body. The hollow candle supposedly drew out impurities when lit. In reality, it posed serious burn risks and could push wax deeper into the ear canal.
13. Smoking During Pregnancy
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For decades, some doctors told pregnant women that smoking could calm their nerves and help manage weight gain. Later research revealed it restricted oxygen to the fetus, causing low birth weight, birth defects, and developmental issues.
14. Butter as a Skincare Treatment
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Butter was once used as a moisturizer for dry skin, especially in rural areas. While it offered temporary softness, it clogged pores and increased the risk of bacterial infections. Dermatologists now recommend non-comedogenic products instead.
15. Low-Fat, High-Sugar Snacks
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In the 1980s and 1990s, food companies marketed low-fat snacks as heart-healthy. To make up for the loss of flavor, they packed them with sugar and refined carbs. This contributed to spikes in obesity and type 2 diabetes rates.
16. Sunbathing for Health
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For much of the 20th century, sunbathing was promoted as a way to get a “healthy glow” and boost vitamin D. While moderate sun exposure is beneficial, overexposure without protection greatly increases skin cancer risk. The tanning trend has left a legacy of melanoma cases.
17. Cough Syrups with Morphine or Heroin
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In the late 1800s and early 1900s, cough syrups often contained morphine or heroin to soothe throats. They were marketed as safe even for children. Addiction, respiratory failure, and overdoses soon proved otherwise.