An episode of major depression may occur only once in a person's lifetime, but more often, it recurs throughout a person's life.

重度抑郁发作可能在一个人的一生中仅出现一次，但更经常的是，它在一个人的一生中反复出现。

Major depressive disorder, also called major depression.

重性抑郁障碍，也叫重度抑郁症。

Major depression is disabling and prevents a person from functioning normally.

重度抑郁能致残并使个人正常机能受损。

However, the modern diet was linked with an increased risk of having major depression.

然而，现代饮食习惯会增加患抑郁症的风险。

People with this disorder may have only one episode of major depression in their lifetimes.

有这种障碍的人也许会经历他们人生中重度抑郁症的一个小段。