Not drinking enough water? Cardiologist reveals how dehydration affects your heart rate and shares 5 warning signs

Does a racing heart indicate you are dehydrated? An expert breaks down how dehydration stresses your heart.

From protein and fibre to water, your body has daily nutritional and hydration needs. There's plenty of health advice on drinking around 2.7-3 litres of water. Individual water requirements may vary, but sometimes you don't feel thirsty, and drinking enough water can slip your mind. How can this dehydration affect your heart health? A cardiologist weighed in on this, revealing the impact on your heart health. Dr Pradeep Kumar Nayak, director and head cardiologist at Dharamshila Narayana Superspeciality Hospital, Delhi, said that dehydration makes the heart beat faster than usual.

Learn why you need to drink water in order to keep your circulatory system healthy. (Picture credit: Freepik)

What happens to your heart when you don't drink enough water?

Now, what exactly is happening in your body when you don't drink enough water? Water is already well known for helping your circulatory system function properly. The cardiologist further emphasised its role in maintaining blood volume. But when you are dehydrated, your body loses more fluid than it takes in.

Now what happens when the fluid levels fall? Dr Nayak described, “As fluid levels fall, the volume of blood circulating through your body can decrease. This means your heart may have to beat faster to help maintain blood flow and deliver oxygen to your organs.”

This is why, Dr Nayak explained, your heart works harder when there is less fluid in your circulatory system. This can lead to a faster pulse, especially after sweating heavily during a workout or spending time outdoors on a hot day. The cardiologist also warned about fluid loss from vomiting or diarrhoea.

What are the other signs of dehydration?

Aside from an increased heart rate, how do you know if you are dehydrated? Dr Nayak shared these signs:

1. Feeling unusually thirsty or having a dry mouth.
2. Darker-than-usual urine or urinating less frequently.
3. Headaches, fatigue or weakness.
4. Dizziness, particularly when standing up.
5. A faster heartbeat or noticeable palpitations.

But these symptoms can overlap with other conditions, so a racing heart alone does not confirm dehydration.

Who is more likely to experience dehydration-related palpitations?

Dehydration can affect anyone, but certain situations make it more likely.

Here are the groups of people who, according to the cardiologist, are more vulnerable:

1. People who exercise intensely:

• Sweating during workouts, especially in hot or humid conditions, can lead to fluid loss.
• If you push through an intense session without replacing fluids, your heart rate may rise more than expected.

2. People working outdoors or in hot weather:

• Prolonged exposure to heat can increase sweating and fluid loss, even when you don't feel particularly thirsty.

3. People experiencing fever, vomiting or diarrhoea:

• These conditions can cause significant fluid loss, making it harder for the body to maintain normal circulation.

4. Older adults:

• Older adults and people taking certain medications may also be more vulnerable to dehydration.

Can drinking water bring your heart rate back to normal?

If dehydration is behind your racing heartbeat, replenishing lost fluids may help. The doctor outlined some immediate steps: “If dehydration is contributing to a faster heartbeat, replacing lost fluids may help your body recover. Start by resting in a cool place and drinking water gradually. After prolonged sweating or significant fluid loss from vomiting or diarrhoea, an oral rehydration solution may be appropriate,” the cardiologist said.

But if your heart continues to race even after adequate rest and fluid replacement, the doctor advised seeking medical attention, as palpitations can also be caused by abnormal heart rhythms, anaemia, thyroid problems, certain medications and other medical conditions.

Note to readers: This article is for informational purposes only and not a substitute for professional medical advice. Always seek the advice of your doctor with any questions about a medical condition.