A new study has found sex can improve people's performance in short-term memory tests.
It adds to the existing research that has suggested sex can improve cognitive function in a number of ways.
Some researchers conclude it is because sex boosts brain cell growth in areas of the brain associated with memory.
Others suggest it's because of the sexual "afterglow" that pumps us full of dopamine and oxytocin.
Either way, sex is probably good for the brain — not that you needed an excuse to have it.
Normally we get by without it being too much of an issue — unless we develop a brain disease like Alzheimer's. But losing your memory can be alarming, and people sometimes worry as it can be a sign of something more serious. That's why there's such an emphasis on memory improvement and brain training in scientific research — people are keen to keep their minds fresh for as long as possible.
According to new research, sex could be one of the ways you can reduce memory loss. The study, published in the journal Archives of Sexual Behavior, was led by Mark Allen from the University of Wollongong in Australia.
Allen looked at data from more than 6,000 adults over the age of 50, and analysed information about their diet, health, well-being, and socio-economic status. They had all also completed a memory task and a questionnaire where they reported how much sex they had. After two years, they completed another memory test.
Results showed that more frequent sexual activity, including kissing and greater emotional closeness, were associated with better memory performance — and this link was stronger among older participants.
Overall, people's memory performance worsened over the two years, and sexual activity only seemed to help with short-term memory tasks. There was no evidence to suggest sex helped declining memory in the long run.
Allen concluded that intimacy may boost memory by stimulating areas of the brain that are associated with memory, like the hippocampus.
Other research supports this idea. For instance, in 2010, a study published in PLOS One found sexual activity could promote the growth of cells in the hippocampus.
Also, a survey of 1,700 people aged 58 to 98, conducted by Manchester University, found people had better brain power if they were still sexually active.
In 2016, results of a study suggested sex could help women to remember abstract words — which is perhaps useful in reducing those tip-of-the-tongue moments. Just last year, more frequent sexual activity was linked to improved brain function in older adults, according to a study by Coventry and Oxford universities.
The Oxford and Coventry study also found that sex improved results of a whole range of tests, including verbal fluency, ability to visually perceive objects, and judging the space between objects.
The researchers said this could be because the "sexual afterglow" produced by the release of hormones dopamine and oxytocin can influence people's perceptions and performance.
While several studies have shown cognitive benefits of sex, both in the long and short term, some results are more solid than others. But the evidence is there that sex has its benefits — just in case you needed an excuse.
Read next on Business Insider: Experts set the record straight on the real reason why you might be having sex dreams