Fasting is one of the oldest health trends, and doing without solid food, as well as a host of other luxuries, is supposed to cleanse the body, proponents say.
While the jury is out regarding the health benefits, doctors are in agreement that it's a risky business for anyone with a heart condition.
First of all, not all fasting is the same.
There's interval fasting, which often follows the rule of 16 hours a day without food.
Water fasting, meanwhile, is particularly strict, and usually means no solid food at all for a week.
Heart specialists advise say that if you have a heart condition, you should definitely avoid the more extreme kinds, such as water fasting.
With milder types of fasting, it is also better to seek medical advice before getting started.
Serotonin, the happiness hormone, is released by fasting and its metabolic changes, which is why many seek to continue their fasting rituals even after a heart condition is diagnosed.
The problem is that a lack of certain nutrients and minerals can have serious consequences for heart disease.
Too little potassium in the body, for example, can worsen cardiac arrhythmias.
Nevertheless, moderate fasting is still possible for people with heart disease.
This can mean cutting down on 500 to 800 kilocalories a day, according to specialists from the heart foundation Deutsche Herzstiftung in Germany.
Doctors also advise against fasting for pregnant or nursing women, as well as for anyone suffering from diabetes, cancer and thyroid conditions. – dpa