Test your knowledge of your own body: which of these health facts are false?

FALSE!

The amount of water you need depends on your lifestyle, diet and the climate you live in. To maintain good health, it's enough to never ignore thirst, drink during the day and between your meals.

FALSE!

Yes, egg yolks contain cholesterol, but eating them doesn't raise your blood cholesterol. Only saturated fats and trans fats can be bad for your cholesterol level.

TRUE!

If you don't like the sound of cracking joints, that's the only way it can hurt you. This specific sound is not generated by the bones – that's how the gas bubbles between them are popping. Cracking joints has nothing to do with arthritis.

FALSE!

The largest organ of the human body is the skin! When it comes to internal organs, the largest one is the liver. It is also the heaviest organ, with an average of 1.6 kilograms (3.5 pounds).

TRUE!

Always look on the bright side. According to numerous studies, optimism is linked to a healthy heart, lower blood pressure and overall healthier behaviors.

FALSE!

It's exactly the opposite.

FALSE!

There is no evidence on this. Consuming too much caffeine may result in a very slight calcium deficit in adults, but this effect can be easily avoided by drinking a tablespoon of milk.