What you need to know about electrolytes
The products are designed to be consumed before, during and after exercise – and manufacturers claim they'll optimise your hydration, health and performance. There are even options to supplement your daily hydration, whether or not you are exercising.
But do you really need to replenish the electrolytes lost in your sweat?
And are sports drinks, electrolyte powders and salty supplements actually the best way to do it?
READ MORE
What do electrolytes do?
Electrolytes are minerals – such as sodium, potassium, calcium and magnesium – that carry an electrical charge that influences how water moves in your body.
'They help maintain the fluid balance,' explained Dr Amy West, a sports medicine physician. They help move fluid into and out of your cells and regulate blood pressure, heart rhythm, muscle and nerve function.
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While they're found in supplements and sports drinks, they're also in the foods we eat every day. 'When we talk about potassium, it's in a banana,' says Heidi Skolnik, a nutritionist. 'When you eat a pretzel, there's sodium on it.'
As you sweat, you lose both fluid and electrolytes and if you lose enough fluid, you can become dehydrated. The volume of blood in your body drops and 'your heart has to pump harder to get the same amount of blood circulating,' Skolnik says.
Do you really need to replace them?
When you lose an exceptionally large quantity of water and electrolytes, as you might if you're having a serious bout of diarrhoea, you need to replace both. In those situations, doctors often recommend a rehydration solution such as dioralyte, which typically has more sodium and potassium than your average sports drink.
But experts say you probably don't need to reach for a sports drink during your regular workouts. Even if those workouts are strenuous or happen in hotter weather, drinking water when you're thirsty is enough to keep you hydrated. The sugar and carbohydrates found in many sports drinks certainly may help competitive athletes maintain their energy, but the electrolytes have little impact.
In the 1990s, standard medical advice recommended sodium-rich drinks for athletes during any exercise that lasted more than an hour. But more recent research has found that even as you lose sodium through sweat and urine, your body maintains the concentration of sodium in your blood. In several small studies athletes didn't tend to report a performance difference between working out with water and electrolyte-infused drinks, even after five hours of running in heat.
It's been well-established for at least a decade that electrolytes don't do much for performance, says Ricardo Da Costa, an associate professor in sports dietetics at Monash University in Australia. 'But the marketing strategies from the sports drinks companies are more potent than the researchers.'
'Everybody thinks that they need to replace lost electrolytes right away,' says Tamara Hew-Butler, a sports medicine scientist. 'You don't. You will make it up generally in your meals.'
Most of the time, you are fine just drinking water when you're thirsty. If you're spending hours outside in the heat for several days and start feeling dehydration symptoms, like lightheadedness, you might reach for a sports drink or supplement, especially if you aren't getting enough electrolytes in your diet, says Robert Kenefick, a professor of biomedical and nutritional sciences at the University of Massachusetts-Lowell.
In rare cases, you can have too much fluid, but not enough sodium in your blood, a condition called hyponatremia, which can cause nausea, fatigue and, in the most severe cases, seizures or death. It's more likely to happen if you have certain medical conditions such as heart, liver or kidney problems.
For athletes, it can happen if they drink so much fluid before, during and after long workouts that it dilutes the electrolytes in their blood. However, most sports drinks don't contain enough sodium to prevent it, says Dr Da Costa.
Is there a downside?
Aside from the cost, experts say there's little downside to consuming electrolyte drinks. As long as you're otherwise healthy, they do not have enough electrolytes to overload your system (called hypernatremia), says Dr Kenefick. And the sweet taste could motivate you to hydrate.
Like most supplements, however, electrolyte products are not well regulated and can even be contaminated, says Dr Hew-Butler. In 2015, she and her team found unsafe levels of arsenic in Muscle Milk and Gatorade powders that had been provided to college athletes. The athletes showed no signs of having been harmed by the exposure.
You won't see 'arsenic' on a supplement label, but you should check for the amount of sugar in the drinks, which can be almost as high as some sodas. As you are reading the label, Dr Kenefick cautioned buyers to be sceptical of what it promises.
'The beverage market is very competitive and everyone's looking for an edge,' he says. 'A lot of the beverages that are out there are using electrolytes as a marketing tool.'
– This article originally appeared in the
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A hero among hormones: Why cortisol is something to celebrate rather than stress about
Of all the hormones produced by the body, cortisol is the most misunderstood. It's essential to any number of biological processes, and yet commonly typecast as 'the one to do with stress' – an evolutionary adaptation for different times, wildly unsuited to modern living, something to reduce with meditation, reset with ice baths or regulate with red-light therapy. Personal trainers will tell you to avoid long runs in case they result in 'cortisol belly', while influencers diagnose 'cortisol face' as a sign of too much pressure in the office. To top it all, social media has recently seen the rise of the 'cortisol cocktail' – a combination of coconut water, orange juice, salt and lemon that TikTokers claim can reduce stress and help with weight loss. But how much of this has any kind of scientific validity ? And is worrying about your cortisol levels doing you more harm than good? 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Try to get some exercise every day, sleep on a regular schedule, and eat as sensibly as you can. Don't worry about the other stuff: you really don't need the stress. – Guardian
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The new paper found that the share of liver cancers resulting from hepatitis B and hepatitis C is expected to drop to 63 per cent in 2050, from 68 per cent in 2022. But the burden of liver cancers resulting from alcohol and MASLD is expected to grow. An estimated four in 10 adults worldwide have MASLD, a condition in which fat builds up in the liver. Risk factors include obesity and Type 2 diabetes. A subset of patients with MASLD will go on to develop an advanced form called metabolic dysfunction-associated steatohepatitis, or MASH, which has been described as a silent killer because it can progress to cirrhosis and liver cancer without being noticed. Current guidance recommends monitoring for liver cancers in patients who have a history of viral hepatitis or established cirrhosis. Patients with MASH typically don't meet that criteria, Dr Kaseb said, but they could have liver scarring without symptoms, and nobody would know. 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'If you stop the reason or the impetus for scarring and injury in the liver, then you're going to have less impetus for the development of cancer,' says Dr Rinella. There is no national liver cancer screening programme in Ireland, so it's important to talk to your doctor about surveillance if you have a liver disease such as hepatitis B or C, genetic haemochromatosis or liver cirrhosis, as the risk of liver cancer is higher. [ Parents facilitating a 16-year-old's 'prinks' is a sign of our weird relationship with alcohol Opens in new window ] Alcohol-related liver disease is also on the rise. In research published in July , Dr Lee and his colleagues showed that the risk of alcohol-related liver disease among heavy drinkers (at least 10 drinks per week for women and 15 for men) in the United States more than doubled between 1999 and 2020, despite similar alcohol use over that period. That suggests that heavy drinkers today may be more sensitive to the effects of alcohol on the liver than those in the past, Dr Lee said. In Ireland, while average alcohol consumption per adult has shown signs of falling, the incidence of binge drinking continues to be pronounced. Drinking heavily and having a metabolic condition such as obesity can independently damage the liver, but patients who fall in both categories are at an especially high risk. These trends are likely to continue. 'Alcohol use is increasing,' says Dr Rinella. 'Obesity and diabetes are increasing.' 'I expect that we're going to continue to see a high burden of liver disease,' she added. – This article originally appeared in the New York Times
