No, this isn't a reference to "Fifty Shades of Grey." This is about the hot flashes that occur as a side effect of menopause and affect up to 80 percent of middle-aged women. Health experts and women have long wondered how long these hot flashes can last, with anecdotal guesses ranging from six months to two years. But a new study has quantified how long this side effect of menopause can last — and the answer is a really long time.

According to a new study published in the Journal of American Medicine Internal Medicine, hot flashes can last as long as 14 years, with an average span of around seven years. 

Hot flashes are bursts of intense heat and sweating that can pop up unannounced during menopause. Night sweats are a similar phenomenon; they occur at night and often disrupt sleep. The exact causes of hot flashes and night sweats are not known, but researchers think it has to do with hormonal changes that occur in menopause and how these changes affect the body's ability to regulate temperature.

In the recent study, researchers evaluated a diverse group of 1,449 women who experienced frequent hot flashes or night sweats and found that the average length of time women endured symptoms was 7.4 years. Some did not experience symptoms for this long, but others had them for far longer, even as long as 14 years. In general, black and Hispanic women experienced hot flashes significantly longer than white or Asian women.

In a cruel twist of fate, researchers also found that the earlier the hot flashes started, the longer they lasted. Women who began getting hot flashes even before their periods stopped were likely to experience them long after the other symptoms of menopause had faded away. They also lasted longer in women who reported feeling stressed, depressed or anxious before they began.

Researchers hope that this new information will help doctors find better and longer-lasting treatments for hot flashes and night sweats. And it may also help to reassure women who for years have wondered when their symptoms would subside. 

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Hot flashes can last as long as 14 years
For the first time, researchers have quantified how long this annoying side effect of menopause can last.