Heart palpitations from not eating enough: what to know

Long gaps between meals may lower blood sugar and prompt adrenaline release. This can cause a fast heartbeat with shakiness, sweating, hunger, weakness, irritability, or light-headedness. Low fluid intake can add dehydration, while inadequate nutrition over time may contribute to anaemia. Palpitations can also happen for unrelated reasons, including atrial fibrillation, thyroid overactivity, medicines, or anxiety. The timing around meals is a clue, not a diagnosis.

Sit down and avoid driving if you feel faint or confused. If you have diabetes, follow your personalised low-blood-sugar plan. Otherwise, take a suitable snack or meal and water if you can swallow safely, then observe whether symptoms settle. Aim for regular balanced meals and fluids rather than relying on stimulants or very restrictive eating. Arrange a medical review if episodes recur, food intake is persistently low, or you have weight change, fatigue, or digestive symptoms.

Get emergency help for fainting, severe confusion, chest pain, severe breathlessness, seizures, or palpitations with profound weakness. If you cannot safely eat or drink, or symptoms do not settle after following your prescribed plan, seek urgent care. Repeated episodes may need assessment for blood sugar, blood count, thyroid function, and heart rhythm.

Could low blood sugar, dehydration, anaemia, or a medicine explain the episodes? Is my eating pattern adequate for my health needs? Should I check my glucose or have an ECG?