We’re taught loads of scientific facts formally or informally from an early age. And they’re all said to be true and reinforced by our common sharing of them. As time progresses, scientists use new methods to find some of those facts (or, in some cases, rumors that are so pervasive they enter the common psyche as perceived true facts) wrong. In this list, we break down some so-called “facts” we believed to be true and show what the science really says.
Drink 8 glasses of water a day
The 8 glasses a day is an overly generalized rule, much like the 2,000-calorie diet. How much water you need depends on the temperature of your environment, your activity level, your size, and other variables.
Water flows the opposite way in the different hemispheres
Water doesn’t flow down the toilet in different directions in the Northern and Southern Hemispheres. The Coriolis effect (the curvature of winds, currents, and other bits moving across Earth’s surface due to the rotation on its axis) is most often cited for the supposed reversed flow, but systems have to be massive for the Earth’s rotation to have any effect. The best example is a hurricane or typhoon.
Middle Ages life expectancy was 30 years old
Though life expectancy was much lower in the Middle Ages, it was nowhere near as low as 30. Life expectancy is more of an average so the high rate of infant mortality at the time pulled the rate way down. Some modern methods don’t factor a person into the average until they’ve reached aged 12.
Overloading on Vitamin C keeps you from getting sick
Drinking orange juice (or downing a bunch of Vitamin C) doesn’t keep you from getting a cold, but it can shorten the duration once you have one.
Don't go swimming for 30 minutes after eating
No more waiting to take a dip after eating. Though swimming at high intensity (think Michael Phelps) may lead to cramps, for those of us not training on an Olympic-level, the old tale of increased blood flow to the stomach for digestion doesn’t cause us to cramp up in the pool. Drinking alcohol and swimming? That’s a different story.