Don't sweat it! Is perspiring good for us?
Sweating is not generally considered to be a good look. Often associated with body odour, most people rely on a daily dose of antiperspirant to stay fresh and dry.
Others embrace sweating, labelling it as "detoxifying". They even encourage the process via Bikram yoga – stretching in a 37°C+ (98°F) room – or regular sauna sessions.
Love it or loathe it, sweating is often unavoidable during the summer – but is it good for us?
Perspiring is entirely natural. It can even be life-saving, preventing your body temperature from reaching dangerously high levels.
"Sweating is a necessary function," Dr Daniel Atkinson, clinical lead at Treated.com, told Yahoo UK. "When we become hot, evaporation from sweat helps to cool us down."
Although mostly water, sweat can also contain small amounts of salt and proteins.
"Sweating pushes water through the [skin's] pores and helps us secrete small amounts of waste, but it's not accurate really to say it's 'detoxifying'," said Dr Atkinson. "It's the liver and kidneys that do most of this work."
Sweat has been found to contain heavy metals and BPA, a chemical in plastic that has been linked to high blood pressure, type 2 diabetes and heart disease.
"A study published in Environment International found the amount of pollutants we excrete through our sweat glands is minuscule," Dr Sarah Brewer, medical director of Healthspan, told Yahoo UK.
Bikram yoga leaves many a fitness fanatic dripping in sweat.
Yoga is known to boost our strength, flexibility and mental wellbeing. Nevertheless, stretching in extreme temperatures may do more harm than good.
"There have been studies to suggest heat can reduce muscle friction and enable muscles to stretch more," said Dr Atkinson. "In theory, this could help the body to temporarily become more flexible.
"Something else about a particularly hot environment is it could help you to ignore muscle pain or discomfort, because your attention is on the heat.
"It's possible this could increase the risk of over stretching and sustaining an injury."
Certain infections – particularly bacterial ones – also prefer warm, moist surfaces.
"[These] can spread more easily in these [Bikram] environments and because you're sweating more, it's easier to transfer these pathogens onto surfaces for other people to pick up," said Dr Atkinson.
People with uncontrolled high blood pressure were traditionally advised to avoid saunas, out of concern the stress of the intense heat would worsen the condition.
Regular saunas may ward off the condition in the first place, however.
In 2017, Finnish scientists analysed more than 1,600 men aged 42 to 60, who did not have high blood pressure at the start of the study.
With saunas popular in Finland, the men who had two to three sessions a week were 24% less likely to develop high blood pressure over the next 25 years than those who had just one sauna every seven days.
Four to seven saunas a week reduced the risk by 46%.
The same scientists later found a half-an-hour sauna reduced blood pressure and increased blood vessel flexibility, with these benefits persisting 30 minutes later.
Nevertheless, Dr Brewer has said: "I would advise not having a sauna unless your doctor agrees and your blood pressure is well controlled."
High blood pressure aside, saunas or steam rooms may boost our mental health.
"The relaxation benefits are obvious, and this can be helpful for mood and mental wellbeing," said Dr Atkinson.
There is also "some evidence to suggest short bursts" may ease chronic pain, he added. On the other hand, taking regular saunas or steam rooms has been linked to reduced fertility in men.
Ultimately, "moderate use isn't likely to cause any health issues and can be mentally beneficial in helping us to unwind", said Dr Atkinson.
Practice safe sweat
For those who enjoy Bikram yoga, have a big bottle of water on hand and sit out certain poses if the heat feels overwhelming.
Saunas and steam rooms usually recommend people limit their exposure to just five to 15 minutes.
"It's essential to 'read the instructions' on the door and make sure you stick to them," said Dr Atkinson.
"These environments are supposed to be relaxing but if you feel yourself start to become dizzy or faint, it's better to step out."
A bottle of water should also be taken into a sauna or steam room.
"Don’t have a sauna alone, or when you are ill or have been drinking alcohol," added Dr Brewer.
When out and about, seek shade when you can and avoid being in the sun during the hottest part of the day – usually 11am to 3pm.
By Alexandra Thompson, Yahoo Life