Many people may put it down to more sunny days, but it may not be that at all – and could be fixed with a simple change
We all know staying hydrated is essential for good health, but the consequences of dehydration can be more serious than just a dry mouth or a headache. Even mild dehydration can take a toll on your physical and mental well-being, and in fact, you might already be feeling its effects without realising what’s causing them.
In a recent study by Liverpool John Moores University, researchers found that people who regularly drank less than the recommended 1.5 litres of water per day had higher levels of cortisol, the hormone responsible for stress. The study involved 32 participants, who were split into two groups.
One group consistently met daily fluid intake guidelines (around six to eight cups, or 1.5 to two litres), while the other group did not. Participants were given just 10 minutes to prepare for a surprise job interview, followed by a mental arithmetic test. Saliva samples taken before and after the task revealed that those who drank less water had significantly higher cortisol levels. So what other surprising effects can dehydration have on your body?
1. Bad breath
As mentioned, when we have a dry mouth it is usually a sign we have not been drinking enough, but Doctor Naveed Asif, GP at The London General Practice said: “While we are familiar with common dehydration symptoms that arise from sun exposure or exercise – such as tiredness, headaches, thirst, dizziness, reduced urine output, dark urine, and a dry mouth – there are several lesser-known effects that can occur if dehydration is not addressed. For instance, bad breath can result from decreased saliva, which normally helps neutralise bacteria in the mouth.”
2. Worsen allergies and sugar cravings
“Allergies may become worse when dehydrated due to increased levels of certain chemicals in the blood that heighten sensitivities,” says Asif. He added: “It’s also common to experience sugar cravings when dehydrated, as the liver requires water to convert glycogen into glucose for energy, leading to lower glucose levels in the body.”
3. Electrolyte imbalance and muscle cramps
“Dehydration has a substantial effect on the body’s electrolyte balance,” says Dr Nadira Awal, Doctify-rated GP. “Electrolytes such as sodium, potassium, and chloride are required for a variety of biological activities, including nerve signalling and muscle contraction.
“When the body becomes dehydrated, the equilibrium of these essential electrolytes can be upset. This imbalance can cause a variety of symptoms, ranging from minor muscle cramps to more serious consequences like involuntary muscle spasms and, in extreme circumstances, loss of consciousness.”
4. Increased risk of kidney stones and UTIs
The kidneys are particularly susceptible to the effects of chronic dehydration. “Insufficient water intake can raise the risk of kidney stones over time by increasing the concentration of minerals and waste materials in the urine,” explains Awal. “This can lead to painful crystallisations in the urinary tract. Moreover, persistent dehydration can put additional strain on the kidneys, increasing the risk of urinary tract infections and potentially contributing to long-term kidney damage.”
5. Drop in blood pressure
Dehydration can also have a significant impact on the cardiovascular system. “As the body loses fluids, blood volume falls, potentially leading to a reduction in blood pressure,” Awal says. “This drop in blood pressure may result in decreased oxygen supply to tissues throughout the body. In severe situations, this can lead to hypovolemic shock, a life-threatening condition in which the heart fails to pump enough blood to meet the body’s requirements.”
6. Premature skin ageing
“Adequate hydration is critical for preserving skin flexibility and health,” advises Awal. “When the body is persistently dehydrated, the skin becomes dry and less elastic, making it more susceptible to irritation and damage. Over time, this can lead to premature ageing and an increased risk of skin problems.”
7. Low energy
“Inadequate water intake is often associated with fatigue and decreased physical performance,” says Awal. “Water transports nutrients and oxygen to cells throughout the body. When hydration levels are low, this process becomes less efficient, resulting in lower energy levels and poor physical performance. This can have an impact on everything from daily routines to athletic performance, thereby increasing the risk of injury when exercising.”
8. Cognitive impacts
The effects of dehydration can also extend to cognitive performance. “The brain is extremely sensitive to changes in hydration status – even modest dehydration can impair mental ability,” Awal explains. “Studies have demonstrated that dehydration can impair concentration, memory, and decision-making. In more severe cases, it can create confusion and disorientation, which is especially dangerous in situations that need alertness, such as driving or operating machinery.”
