A little overindulgence on Christmas Day seems harmless enough. After all, it’s just one day, right? Yet each year on Christmas Day more people die than on any other day from sudden cardiac arrest. Is it the excitement or stress of family gatherings? Or are extravagant Christmas dinners dangerous for our health?
Sudden cardiac arrest occurs when the heart develops an abnormal rhythm, or arrhythmia, that causes it to stop beating and pumping blood to the brain and other organs. Cardiac arrest differs from a heart attack, in which the heart usually continues to beat despite its blood flow being blocked.
Typical cardiac arrest signs include sudden collapse, loss of consciousness, no breathing or pulse and skin turning pale or blue. Without prompt medical attention, death occurs within minutes. Cardiopulmonary resuscitation (CPR) or, ideally, defibrillation (which gives the heart a small shock to restore its rhythm) must be started immediately, as every minute’s delay reduces survival chances by about 10%. See “In for a shock” (December 8) for more about automated external defibrillators.
In New Zealand, about 1500 people suffer sudden cardiac arrest each year and 90% die as a result. Millions of people worldwide die of cardiac arrest each year, most in winter, and many on celebration days such as Christmas and New Year. There’s a well-established link between heavy alcohol consumption (more than six drinks a day) and increased cardiac arrest risk.
Furthermore, stress-related catecholamine hormones have also been shown to cause the arrhythmias associated with cardiac arrest. However, a hypothesis recently published in the Journal of Applied Toxicology adds overeating to the mix.
Christmas Day may create a perfect storm: excitement, stress and excessive food and alcohol intake – especially for genetically susceptible people – raising the risk of sudden cardiac arrest that almost inevitably results in death. Underpinning this hypothesis is a system of enzymes that our body uses to deactivate the catecholamine stress-related hormones. These SULT1A enzymes are naturally less active in winter, coincidentally when most sudden cardiac arrests occur.
Evidence also suggests phenols and polyphenols found in many plant-derived foods can inhibit these enzymes, thereby allowing higher levels of stress hormones to accumulate in our body, possibly leading to arrhythmias. Furthermore, genetic differences may make some people more susceptible to SULT1A inhibition.
Phenols and polyphenol compounds are found in most alcoholic drinks (especially red wines), herbs, spices, citrus fruits, berries, coffee, tea, chocolate, onion, tomato and many other plant-derived foods. But before you throw the red wine and salad off the Christmas menu, consider this.
On Christmas Day, we typically consume more alcohol and food than on any other day of the year, so if this theory is correct (and that’s not yet proven), the food supply is not inherently unsafe. Nor will overindulgence in food and drink cause cardiac arrest in everyone. But, rather, it’s hypothesised that some genetically susceptible people may need to moderate their food and alcohol consumption, particularly when combined with stress or excitement.
Regardless of whether this hypothesis turns out to be correct, there are still many benefits to being a responsible host on Christmas Day, not least in ensuring your guests have a safe and enjoyable time. Make physical activity part of your celebrations – try pétanque on the back lawn or a walk to the park or beach. Insert it between the main meal and dessert to slow down fast eaters and drinkers.
The greater the variety of food offered the more we eat – there’s no need to skimp on quantities, just slightly limit the variety on your menu and you’ll help guests moderate their intake. Regularly offer your guests water or other non-alcoholic drinks between alcoholic drinks. Place pitchers of iced water and water glasses on the Christmas dinner table – the closer they are, the more people will drink.
Conversely, place alcoholic drinks on a side table to slow consumption. Likewise, moderate food intake by placing dishes on a side table rather than the dinner table – out of sight, out of mind.
Email: email@example.com, or write to “Nutrition”, c/o Listener, PO Box 90783, Victoria St West, Auckland 1142.