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Depression; I can say it does kill faster even more than the most deadly disease in the history of the world, Depression cannot directly kill you the way that an illness like cancer or tuberculosis might, but it can have certain effects that could lead indirectly to a person being more likely to die. Seeing this indicating that the depressed mind is likely to meet his death unprepared for. 
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The most obvious way that depression might lead to death is if the bad feelings of depression has eaten deep the heart of the person affected, it shows that such has lost hope of everything one ever wanted, the reason to always seek people help in terms of need shouldnt be over emphasize. We all need one another in the life, a tree alone cannot make a forest, so we all must be there for one another and never to take things personal at all time. We should always learn to make people happy with our behavior and attitude and not otherwise since we never know the person sitting beside us is going through.
Depression can make people feel helpless and without hope, causing them to reach the unfortunate conclusion that suicide is the only way to end their misery, always be open when the going seems not to be good and encompasses greater challenges, remember we need one another in this life
always be open with people
(don't keep thing to yourself)
Consequences of depression can include:
increased risk of suicide, unstable mind is prone to commit suicide
an increase in the production of stress hormones like cortisol
decrease production of sex hormones and reduce sex drive
can cause permanent memory damage if untreated
increased risk of stroke, asthma, heart disease, cancer, pneumonia
an elevated risk of returning to addictive behaviors such as smoking, drug use, or drinking
aggravated feelings of anger and hostility towards oneself and other people in the community