Winter immune system myths and musts
The middle of winter is here. No matter how healthy you think you are, the flu virus and various colds are abound and they’re ready to infect your system.
There are some ways to boost your immune system and stay healthy for the rest of the chilly, virus-laden season, but a lot of what we think true is mythical.
First and foremost, hydration is key. When it’s not warm outside we often drink less water, but dehydration can lower the body’s defences. The eight glasses of water a day rule still rings true; However, an easier way to ensure you’re never dehydrated is to look at the colour of your urine. If it’s a pale yellow or clear, you’re getting enough water.
While you’re thinking about fluids, make sure you’re drinking cow’s milk. Milk is a good source of protein and also contains vitamins A and B12, which benefit your immune system. There’s also milk’s calcium factor, which you know keeps bones strong too.
Owing to a lack of sun, our bodies can become vitamin D deficient in winter. You can consider taking a vitamin D3 supplement until the sun’s rays come out again, though food sources such as fish, eggs and mushrooms do contain good doses of it.
Not only does the body not produce vitamin C by itself either, if you’re physically or mentally stressed you require 20-40 times more of it to maintain optimal levels. This can’t be neglected in winter, so it remains important to eat citrus fruits.
Having a good level of zinc in your body too (it comes from beef and lamb, nuts and seeds, and shellfish) may help shorten the length of the common cold. When combined with vitamin C, zinc is can also help heal scrapes and wounds faster.
Aside from these primary dietary interventions, your best bet in having a strong immune system throughout winter is to keep up (or increase) your exercise, and eat protein to repair your muscles. The immune system runs on protein, which is why the old wives’ tale of chicken soup for generally illness is potentially true: chicken is high in protein, and the broth is a good source of fluids.
Some winter wellness old wives’ tales are no more than myths, however. Echinacea was proven in Annals of Internal Medicine journal to be ineffective in preventing or treating colds. In this randomised controlled trial, there was no difference in health outcomes for those who took a placebo, or those who took no supplement at all. So-called ‘‘small preventative effects’’ of echinacea haven’t been ruled out in other studies, but there’s no good evidence to support them either.
Any other supplements that market themselves as beneficial for ‘‘immune system defence’’ (or similar) are also unlikely to be based on any science. There’s very little evidence that any supplement can boost the chemical components of your immune system – that system’s repertoire is made up of thousands of genetic elements.
The vitamins and various other treatments from health stores that claim they can prevent or cure general coughs and colds are not backed up by solid proof. They may be helping specific parts of your system (e.g. boosting vitamin D, C, and zinc quantities), but cannot be relied on to improve your overall immune system during winter.
It’s also important to understand that from a scientific point of view, there’s also a big downside to having a seasonally souped-up immune system. Researchers from the University of Cambridge found that while a seasonally increased immune defence system helps fight off infections such as colds and the flu, it also raises inflammation in the body. The study found that the immune system’s activity boosts during winter to stave off infections and relaxes during summer when it is less needed.
Unfortunately, what this winter boost of inflammation does is raise your risk of heart attacks, stroke, severe cases of depression and other mental health disorders, and Alzheimer’s disease. Generally, as these Cambridge scientists suggest, the enhanced risk factor for disease when a person’s immune system is seasonally boosted may outweigh the benefits of being able to fight off less serious colds and influenza viruses.
Lee Suckling has a masters degree specialising in personal health reporting. Do you have a health topic you’d like Lee to investigate? Send us an email to life.style@fairfaxmedia.co.nz with Dear Lee in the subject line.