Is it REALLY that bad to eat food after it fell on the floor?

Normally yes, only if the floor is kept hygienic. If there is continuous surface bacterial count test or hygienic control of the surface and the result is negative or minimum, in that case it would be fine. But as a general practice, avoid eating/consuming/selling those foods that come in touch with floor (dirty surfaces). 

Depends on the food: if is a fruit or vegetable, or something that can be washed and will be cooked is not a disaster. But if you drop down some ready to eat food is better to live even if is your own floor.

It depends on  food and floor environment, if the food requires cooking or processing before consumption, it can be picked from the floor. If an environment is filthy or unhygienic and requires some sanitation, it will better to either process it for pasteurization or not consume it. 

 

Transfer of bacteria to the dropped food is immediate. Type of food, floor surface materials, degree of floor contamination and concentration of pathogenic bacteria are the most important factors in the safety of dropped ready to eat food. On the other hand, microbial contamination of dropped moist food is more likely than dry food. Furthermore, safety risk of a contaminated surface and a high concentration of a pathogen are high, although some strains of bacteria are extremely virulent. For example, 10 cells or less of an especially virulent strain of E. coli can cause illness.

 

So, in spite of suggestion the five-second rule by some researchers, really there is no safe window for dropped ready to eat food. Whole fruits and vegetables which can be washed after falling to the ground may be exempted.

 

 

Depends on the food ,

if its ready to eat food ( like Cheeses , cakes, ready salad ......) and you cant clean it after fell on the floor for sure its bad  

but if it food under process that you can wash and can cook its OK .

its depended where it is fell

If it uncooked and not cut like fruits and vegetables can be washed and eaten, if was cooked or if you cut - such as salad can not be eaten because of dirtying food .