The heart is used to pump blood around the body, according to the NHS.
Having a healthy heart is crucial to a healthy life, as organs around the body need a constant supply of blood for fresh oxygen.
Taking some supplements could lower the risk of some heart-related health conditions, said cardiologist Dr Stephen Sinatra.
Magnesium supplements could improve the efficiency of heart cells, he said.
They may even help to protect against high blood pressure and arterial plaque.
“I can’t stress enough how crucial magnesium is for your health,” said Sinatra.
“This amazing mineral is a vital player everywhere in your body and is extremely beneficial for heart health.
“Magnesium improves the metabolic efficiency of heart cells and therefore is a useful treatment for a whole host of cardiovascular conditions.
“When taken regularly, this mineral can help maintain vascular tone, and therefore helps promote healthy blood pressure, and may also help reverse arterial plaque.
“Magnesium also acts as a muscle relaxer inside the arteries, helping to alleviate chest pain and other symptoms of angina that are caused by lack of oxygen to, or energy in, the heart.”
But, the NHS suggests taking no more than 400mg of magnesium in a single day.
Too much magnesium can lead to diarrhoea for a short period of time, it said.
The recommended daily amount of magnesium for men is 300mg, while women should aim for 270mg.
Most people should be able to get all of the magnesium they need from their diet.
Eating a healthy, balanced diet may help to lower the risk of some deadly heart conditions, including heart disease.
Slash your risk of heart disease by eating more fibre.
Everyone should eat about 30g of fibre every day, it added.
Keeping active could also help to keep your heart healthy, said the NHS.
All adults should aim for at least 150 minutes of moderate-intensity activity every week.