The next time you’re tempted to brush off that cookie you dropped on the floor and pop it in your mouth, you might want to think twice. The “five-second rule,” which claims it’s safe to eat to eat fallen food as long as it’s quickly scooped up, is bogus, according to researchers at Rutgers University.
“The popular notion of the ‘five-second rule’ is that food dropped on the floor, but picked up quickly, is safe to eat because bacteria need time to transfer,” Schaffner said. But it’s not quite so simple. “Bacteria can contaminate instantaneously,” he added.
The longer food was in contact with a surface, the more bacteria was transferred. “Although this research shows that the five-second rule is ‘real’ in the sense that longer contact time result in more transfer, it also shows that other factors, including the nature of the food and the surface, are of equal or greater importance,” the researchers wrote in their paper, which was published in the journal Applied and Environmental Microbiology.
Thus the five-second rule joins other misconceptions about food we now know are based on fiction rather than fact. Here are five other food myths you might want to take with a grain of salt.
1. Some foods have negative calories
For dieters, the idea that there are negative-calorie foods is pretty amazing. Celery is supposedly one of these miracle foods that burns more calories through digestion than the number of calories you actually end up consuming. It’s the same with apples, lettuce, and cucumbers. Unfortunately, negative-calorie foods don’t exist.
“Foods that contain few calories, such as celery and other nonstarchy vegetables, provide a small number of calories but still require energy to digest. That means it is theoretically possible to have a negative-calorie food, but there are no reputable scientific studies to prove that certain foods have this effect,” Mayo Clinic says.
2. Sugar makes your kids hyper
Feeding kids sugar doesn’t cause them to bounce off the walls. The notorious “sugar high” that parents say happens after their kids indulge in candy or cake has little to do with the ingredients in the food and more to do with mom or dad’s expectations.
Parents who believe sugar makes their kids extra energetic are more likely to rate their child’s behavior as hyperactive after they eat a sweet treat, a 1994 study found. Plus, kids often consume lots of sugar at birthday parties or holiday celebrations, when they’re already likely to be excited. “People may have confused proximity with correlation although the environment is probably more to blame than the food,” reads a report in Yale Scientific.
3. Chewing gum stays in your stomach for 7 years
As a kid, someone may have warned you to not swallow chewing gum because it would stick to your stomach for seven years. But this persistent urban legend is more scare tactic than sound advice, pediatric gastroenterologist David Milov, told Scientific American.
If you swallow a piece of gum, it usually passes through your digestive tract without incident. However, consistently swallowing your chewing gum may cause problems. At least two kids developed gastrointestinal blockages after consistently swallowing gum, which they received as a reward for good behavior. Doctors have also reported cases of patients who had masses in their stomach or esophagus formed by a combination of gum and coins or the shells of sunflower seeds. So, while swallowing the occasional piece of gum isn’t cause for concern, it’s not something you should make a habit of doing.
4. Eggs are unhealthy
For years, eggs have gotten a bad rap because of their high cholesterol content. People whipped up egg white omelets (since the yolks contain most of the dreaded cholesterol) or shunned eggs entirely in the name of good health. But it turns out eggs aren’t the diet disaster people thought they were. In fact, they’re pretty healthy.
“While it’s true that egg yolks have a lot of cholesterol — and so may weakly affect blood cholesterol levels — eggs also contain nutrients that may help lower the risk for heart disease, including protein, vitamins B12 and D, riboflavin, and folate,” explained Harvard School of Public Health. The cholesterol in foods we eat doesn’t have a big effect on blood cholesterol levels, which are more affected by the mix of fats in our diet, health experts now know. One egg per day is generally safe, though people whose cholesterol levels aren’t well controlled may want to stick with the egg whites.
5. Organic food is always more nutritious
Eating organic food may feel healthy and virtuous, but does steering clear of foods grown with synthetic pesticides or that contain artificial flavors or preservatives really make us healthier? Scientists aren’t convinced.
“There isn’t much difference between organic and conventional foods, if you’re an adult and making a decision based solely on your health,” said Dena Bravata, M.D. and the senior author of a 2012 paper comparing the nutrition of organic and non-organic foods. Bravata conducted a meta-analysis of existing studies and found no strong evidence to support the belief that organic foods were more nutritious than non-organic foods. The results were published in Annals of Internal Medicine. Eating an organic diet didn’t reduce the risk of cancer, with the possible exception of non-Hodgkin’s lymphoma, according to a separate 2014 study of more then 600,000 British women.
Yet there’s some evidence organic foods might be superior to non-organic foods. Organic meat and dairy products have more omega-3 fatty acids, while organic crops have more antioxidants, according to two separate meta-analyses, both published in the British Journal of Nutrition.
The question of whether organic is healthier isn’t settled. In the meantime, most health experts do agree we should all be eating more fruits and vegetables, organic or not.
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