1. Drink cactus water if you are lost in the desert.
In fact, if you're lost in the desert and thirsty, hang in there. Drinking cactus water is a myth that can kill you, since the liquid from these plants – besides being quite difficult to extract – contains toxins that will make things worse for you, causing vomiting and cramps.
2. If a shark attacks, punch it in the nose.
Myth and death! The truth is that water slows you down considerably, and if you hit the animal in the nose, the chances of it becoming more irritated than stunned are much higher.
Ideally, you shouldn't expose yourself to this type of danger; however, if a shark attack ever happens, attack the animal's eyes and gills as quickly as possible with something sharp. This may prevent the shark from killing you.
3. In case of an earthquake, take cover under the door frame.
This is another myth that can kill anyone who tries it. That's because in modern constructions, door frames or portals are fragile and cannot withstand the impact of the rest of the building collapsing. In the past, however, the myth was even valid, since door frames were very resistant. Nowadays, it's better to run under a table.
4. If bitten by a snake, suck out the venom.
According to Strauss, this is a myth and attempting it is pointless, as snake venom can spread rapidly through the bloodstream. Furthermore, trying to suck the venom from the open wound can introduce bacteria to the injured area, further increasing the risk of death.
The only thing you can really do is try to stay calm to reduce your heart rate and buy time until you reach a doctor who can administer the appropriate antivenom.
5. If stabbed, remove the object.
Please don't do that, it could kill you! This is another fatal myth, as removing a knife, arrow, or any other sharp and/or pointed object can cause further injuries and lead to severe bleeding.
In such situations, the best thing to do is remain still until a doctor or firefighter removes the object from your body correctly, in a place where the necessary first aid can be administered.
6. If lost in a frozen place, eat snow to stave off hunger.
Instead of starvation, this myth can kill you. In a cold place, to the point of having snow everywhere, your body temperature will already be low. If you then eat the snow, it's very likely that your temperature will drop even further.
The most you can do in these cases is try to melt the ice and drink the liquid at a more suitable temperature.
7. During thunderstorms, lie down on the ground outdoors.
Absolutely don't do that. Lightning can strike the ground and kill you with the electrical discharge, burning your body or causing a heart attack. So, forget that myth and try running crouched down, especially if it's in a tight space.
This is because lightning rarely strikes moving objects, even more so if they are lower than other exposed and stationary objects, such as trees (under which you should also never stand).