Having friends who cause you stress can make you unhappy, which can in turn

increase your lifespan
lead to health problems
lead to better mental health
improve schoolwork

lead to health problems

Explanation:

Unhappiness can lead an individual to develop health problems.

The main consequence of unhappiness is manifested in stress, which is closely related to human health. The reflection of all this 'widespread unhappiness' is accompanied by the increase in anxiety levels and emotional and behavioral problems, mainly expanding the cases of depression in both sexes, which requires attention and care. Epidemiological studies on mental health worldwide point to depression as a cause of illness of up to 20% of the entire population. In addition, the stress caused by unhappiness can trigger a series of problems not only in mental health but also in physical health.

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