Problems can occur if your thyroid gland does not produce the correct level of hormones that control vital functions in the body. And having too much or too little of the hormones can cause thyroid disease and can lead to muscle aches, tiredness, depression and fluctuations in weight.

Here's a guide to understanding "particularly dangerous situation" red flag warnings, containment, and other terms related to the devastating fires that have left much of the LA area in ruins.