Facebook Twitter

World War II Propaganda: Carrots, Muscle and Willpower
Myths About Health and Fitness

Interval Sprints
This image was created by the United
States Department of the Treasury
and was provided by the National
Archives and Records Administration.

Spoiler alert! Some “facts” you were told while growing up aren’t true. Keep reading for the revelations.

When I was eight years old, I knew two things about carrots. Rabbits loved them, and they're good for my eyesight. If I ate enough, my vision would improve so much I could see in the dark.

Well, at least the part about rabbits was true. They love them, but rabbits have to eat a well-balanced diet just like people, and carrots would be unhealthy if they ate them all day. The part about carrots being good for your eyesight is a mashup of wartime propaganda and a misunderstanding of medical treatments.

During World War II, scientists in the United Kingdom developed a radar system to detect hostile incoming German aircraft. Before those planes could be seen or heard, the British knew where the enemy was. Fighters were sent to intercept and stop the attacks, saving thousands of lives.

Keeping the radar a secret was vital. So the British Ministry of Information started a campaign to promote carrots and “leafy green or yellow vegetables...for night sight.” The British pretended that eating large amounts of carrots was why their fighters were so successful. It worked. Germans gave their pilots more carrots, but didn’t figure out the radar system. The belief in that propaganda myth has endured to this day.

But that’s only half the story. Our bodies convert beta-carotene, the nutrient that turns carrots orange, into vitamin A. Healthy eyesight relies on vitamin A, and many people in developing countries don’t get enough.

When researchers enriched diets with vitamin A for six weeks, subjects with poor night vision could restore their sight to normal. Vitamin A didn’t enhance normal vision; it corrected the vision in people who were deficient.

Mix the propaganda myth about carrots giving you night vision together with the research showing vitamin A can restore night vision, and you have the perfect mashup that people still believe today. “Eat your carrots for night sight.”

That got me thinking about some of the other everyday health and fitness myths people still believe.

MYTH: If you quit working out, all your muscles will turn into fat.

TRUTH: Nope, not a possibility. Muscle is mainly made up of protein with some amino acids and water. Fat is adipose tissue. You can’t change muscle into fat any more than you can change a cat into a dog.

When you quit working out, the muscle shrinks. If you’re eating the same amount of food, your body still has to process all those calories. If you’re not burning them off or using them to build muscle, your body turns them into fat. So as your muscles shrink, your fat cells expand.

The good news is, if you worked out and had good muscular development when you were young, you’ll have an easier time putting that muscle back on when you’re older. Several studies now show muscle memory is a real thing. In essence, you can “bank” muscle when you’re young to draw on later in life.

MYTH: You’ll succeed with your diet and workout plans if you have enough willpower.

TRUTH: Willpower diminishes over the course of a day. Every time you take a stand, you reduce your ability to do the same thing later. People who succeed take steps to alter their situations, to make straying harder. Here are three examples.

One, remove temptations. Only keep food in your house that’s healthy. It takes a lot more effort to drive someplace and buy ice cream than to grab a pint out of your freezer. Don’t keep indulgences around to tempt you.

Two, start doing something physical. Meet a friend for a walk, download a fitness app or join a gym. When we exercise, it strengthens the prefrontal cortex, the area of the brain used for rational decision-making. People who engage in physical fitness are less likely to act on impulses or temptations.

Three, focus on one goal at a time. Don’t make a list of 50 things you’re going to change because it’s overwhelming. Choose one thing for 60 days and make it a habit. Once it becomes part of your routine, move to the next thing.

Were you a believer in any of these fitness myths?

Call for a FREE Consultation (305) 296-3434
CAUTION: Check with your doctor before
beginning any diet or exercise program.