Palpitations
Palpitations are often caffeine, stress, alcohol, poor sleep or low iron. When they need a GP the same day, what a blood test shows, and what people look at afterwards.
What is usually behind it
Palpitations, the feeling of your heart racing, pounding or skipping, are common and usually harmless, but this is a page where the GP line comes first.
See a GP the same day, or call 111, if palpitations come with chest pain, breathlessness, fainting or near-fainting, or if they last more than a few minutes and keep happening. Call 999 for chest pain with palpitations.
For the rest: the ordinary causes are caffeine, alcohol, nicotine, stress and anxiety, poor sleep, dehydration, an overactive thyroid, and low iron or low magnesium. A blood test can show iron stores, thyroid function and, less usefully, magnesium. Free blood test result interpreter.
What people look at after the check. Magnesium, which contributes to electrolyte balance and the normal functioning of the nervous system; iron where ferritin is low. Magnesium raises heart rate variability modestly in trials, mainly in people under training load or with low intake (evidence).
Next: the magnesium collection · Nutri365, which reads Oura HRV alongside what you report.
Written by Nutri Tailor from the Health Reference Library. Last checked 6 September 2026. General information, not personal advice.