Winter is here and there’s no escape from the icy cold mornings and nights. While you’re preparing for the drop in temperature by bringing out your thermals and thick cosy blankets, it’s important to also prepare your diet accordingly. This can be confusing at times when your family give you their top winter tips that have been tried and tested for years but ‘Doctor Google’ contradicts these. Who do you believe? Freeze! It’s time to play detective and rely on science-based evidence to bust a few of the most common winters myths.

1. MILK MAKES MUCUS WORSE- AVOID IT WHEN YOU HAVE A COLD 

The first thing your grandparents may tell you to do when you have the sniffles is to avoid milk, so this one may come as a surprise to many. Studies conclude that there is no link between milk consumption and mucus production or asthma. Interestingly, one study in particular revealed that participants infected with a common cold virus said that after drinking milk they had symptoms of an increase in mucus production. When mucus production was measured there was however no statistical difference1. Consumption of milk therefore does not increase mucus production. It is postulated that this sensation may be due to the texture and viscosity of milk. In contrast, research shows that the major components of bovine milk products modulate immune function2.

2. AN ORANGE A DAY KEEPS A COLD AWAY

As soon as winter hits, people start stocking up on vitamin C supplements and vitamin C rich fruits such as oranges to fight off a common cold. A meta-analysis of 72 studies which examined the benefits of regular vitamin C supplementation revealed that vitamin C does not lower the incidence of colds, except for people who are exposed to short periods of physical stress such as athletes and marathon runners3. Vitamin C doses from about 1 gram daily may however shorten the number of days you are sick when you get a cold4. So, although oranges may not necessarily keep a cold away, we’re not saying you should stop consuming them during winter. Enjoy oranges and a variety of other fruits and vegetables daily during winter to ensure that you meet your daily vitamin and mineral requirements. If you do get a cold, you may consider vitamin C supplementation of at least 1g daily. If you’re going to rely on food sources of vitamin C, one medium orange only contains about 59-83mg of vitamin C so be sure to include other sources of vitamin C in your diet such as broccoli, cauliflower, red bell peppers, green bell peppers, brussel sprouts and papaya5.

3. YOU NEED TO EAT MORE TO STAY WARM

Cold fruits and salads are out and comfort foods are in. Even your exercise routine gets neglected because you’d rather be under a pile of warm blankets than doing any form of physical activity. It’s no surprise that most people therefore tend to gain weight during winter. It is also a common belief that you need to eat more to stay warm. This stems from the belief that thin people feel colder because they have less fat stores and ‘no insulation’. The truth is that how cold you feel is not just dependent on body weight and size. There are a variety of other contributing factors such as gender, age, sleep patterns, diet and lifestyle6. Eating more will therefore not keep you warm. Don’t fall into the trap of laziness and comfort foods. Summer bodies are made in winter so make sure that you stay active (you can even do home workout if you can’t get yourself to the gym) and control your calorie intake all year round with a healthy, balanced diet. 

4. ALCOHOL WARMS YOU UP

Yes, the cold can be unbearable at times. Thermals and heaters are not always sufficient to keep you warm so some may turn to alcohol to warm up- perhaps an Irish coffee or a glass of wine. Does alcohol actually do the trick to warm you up? The answer is no. When you feel cold this usually occurs from blood flowing away from your skin and into your organs thereby increasing your body core temperature. The consumption of alcohol causes a reverse in this process. The flow of blood to the skin is increased thereby causing a drop in your body core temperature7. So, although your skin may feel warm, your vital organs aren’t as warm as you think. Alcohol is not only a false indicator of warmth but it can also be one of the culprits of your winter weight gain as it increases your daily calorie intake.

5. CHICKEN SOUP WILL CURE A COLD

One of the food remedies that come to mind when a person has a cold is chicken soup. This makes sense as the chicken provides a good source of protein and the vegetables provide vitamins and minerals. If a healthier option of a carbohydrate such as whole-wheat noodles is added, they can provide a source of energy as well as fibre. Chicken soup is also a delicious way to warm up and stay hydrated. The science behind this remedy is that the inhalation of the warm vapour of chicken soup causes a rise in temperature of the respiratory passages thus loosening thickened secretions8. In addition to this, research has shown that drinking hot fluids increases nasal mucus velocity and that hot chicken soup appears to have additional substances for increasing nasal mucus velocity when compared to hot water9. Chicken soup also reduces the movement of neutrophils (white blood cells produced during the immune response to a cold) resulting in the reduction of the amount of mucus and inflammation10. If you’re going to make chicken soup, remember to add active ingredients known for their antioxidant and medicinal properties such as celery, parsnips, carrots, onion, mushrooms and parsley11. So, the good news is that chicken soup may provide relief of symptoms of a cold. The bad news is that it won’t actually cure your cold.

Sometimes there’s a scientific explanation as to why grandma’s famous remedy works wonders. Other times the old ‘they say’ statement isn’t actually true. Now that you have all the facts, all that’s left to do is stay warm and informed!

1. http://www.abc.net.au/health/talkinghealth/factbuster/stories/2007/11/28/2102703.htm
2. https://www.cambridge.org/core/journals/british-journal-of-nutrition/article/immunomodulatory-properties-of-milk/A78B6F74F2AD20FD50CFAC802B3C0FBC 
3. http://cochranelibrary-wiley.com/doi/10.1002/14651858.CD000980.pub4/abstract
4. https://www.ncbi.nlm.nih.gov/pubmed/10796569 
5. https://www.dietitians.ca/Your-Health/Nutrition-A-Z/Vitamins/Food-Sources-of-Vitamin-C.aspx 
6. https://www.news.com.au/lifestyle/health/why-some-of-us-are-always-cold-and-others-are-constantly-hot/news-story/39106d8e9304da403171413c546c9526 
7. https://www.drinkaware.co.uk/advice/staying-safe-while-drinking/alcohol-and-cold-weather/ 
8. http://www.ent-consult.com/abstract.html 
9. https://www.ncbi.nlm.nih.gov/pubmed/359266 
10. https://www.ncbi.nlm.nih.gov/pubmed/11035691 
11. https://www.ncbi.nlm.nih.gov/pubmed/8923020