During the endless covid lockdowns, we — as a family — have been very healthy and have almost forgotten even what it was like to have more than the occasional sniffle due to seasonal allergies. However, as our doors have opened and we have re-started our lives outside of our four walls, all the ailments that had been lurking just outside our doors, all through the year, including the common cold and flu, suddenly arrived.
Now, exposed to everything, we have broken out a tissue box and are on a steady supply of medicines to help clear our noses, relieve our coughs and break our fevers. I’m constantly running behind at least one sick person, prompting them to eat to give them the strength to fight off whatever is attacking their body. This has forced me to look at how nutrition may play a role in infection and virus prevention.
While researching, I was reminded of the age-old adage, “Feed a cold, starve a fever.” So I started to wonder if there any real merit to this? And how should we eat to prevent and minimise the symptoms of illness?
When I did some further research, surprisingly few studies had really researched the phrase. It was beginning to feel like something a jaded scientist would like to prove their mother wrong many years ago. The unproven theory behind this statement is that fasting helps lower body temperature during a fever. One Dutch study published in 2002 in the Clinical and Diagnostic Laboratory and Immunology Journal, titled Feed a Cold, Starve a Fever had studied this theory in some detail. Since the study only contained six males, all mid-20s and all relatively healthy, you should be aware that these experiment parameters are less than ideal.
What they found in the experiment was that there was a link to eating and how it modulates our immune response. Eating food showed an increase of 450% in gamma interferon production, indicating cell-modulated immunity (which works best for virus-infected cells). In addition, food created an antibody-mediated immunity, which could help fight off infections most associated with fevers. With very few studies on hand, this is an exciting place to start, but it certainly doesn’t prove the theory correct.
Where we run into trouble is this: you can have a cold and a fever simultaneously, Also, fevers can arise as a response to both bacteria or viruses. So now what? How do you know when to starve and when to feed?
Doctors now advise you to listen to your body and eat what you can keep down, at least enough to maintain strength and fight the illness. And yes, opting for the right foods can make a world of difference. Chicken soup, for instance (yes, your grandmother was right here), is full of nutrients, calories, and electrolytes and will soothe your throat and tummy too.
What’s more important when you fall sick is to ensure that your fluid intake is high enough to help flush the sickness out of your system. According to an article in the Scientific American titled Fact or Fiction: Feed a Cold, Starve a Fever, the author, Fischetti, tells us that dehydration makes the mucus in the nose, throat, and lungs dry up, which can then clog sinuses and respiratory tubes. “When mucus hardens, it becomes more difficult to cough, which is our way of trying to expel mucus and the germs it contains. Staying hydrated helps keep the mucus running, which, even though it may be disgusting, is one of our natural defences,” he says. In short, drinking plenty of soups and fluids throughout the day is critical.
As another adage goes, prevention is better than cure. So let’s backtrack the story and assume that no one even wants to get sick. How can we use our nutrition to ensure that we can minimise our likelihood of getting sick?
Some examples of nature being a great pharmacy lie no further than some everyday products we find in our pantries. For example, garlic has been touted as great antibiotic food and used by many cultures over centuries to prevent and treat ailments. Likewise, green tea is believed to increase B-cell antibody production, which helps us rid pathogens from our bodies. Similarly, honey is an effective cough suppressant in both children and adults.
70% of immune cells are found in our gut, so we must protect our gut health. You can do this by eating lots of natural foods full of fibre. Diets high in processed foods or low in fibre make it easier for us to have poor gut health and, therefore, less able to fight off infection. The best sources of probiotic foods that you can enjoy are fermented dairy products, such as yoghurt, curd, and kefir, and fermented vegetables, such as kimchi and sauerkraut.
A diet full of fresh fruits and vegetables is crucial because nutrient deficiencies, especially chronic ones, can lead to poor immune function. According to the authors of the paper titled Feeding the Immune System, the inadequate intake of many vitamins and minerals such as iron, zinc, magnesium, manganese, selenium, copper, and vitamins A, C, D, E, B6, B12, and folic acid may all decrease your immune defence. Multivitamin supplementation is possible if you’re struggling to ensure you get the right micronutrients.
Obesity is a driver behind lower white blood cell count. According to the study Obesity and Immune Cell Counts in Women, the “increased number of immune cells associated with obesity may be the result of a chronic inflammatory state due to increased cytokine production by adipose (fat) tissue.” Inflammation can act as a “false alarm” in the body – the more there is, and the body responds to it, the less your immune system will react to sickness in the future. Minimising unnecessary weight gain can keep inflammation at bay and your immune system firing as it should.
Sugar and processed food
Diets which are high in sugar can be pro-inflammatory as well. However, a diet that includes more Omega 3 (fish oil, nuts, seeds, etc.) and fewer Omega 6 (processed foods and some cooking oils) can help rebalance the inflammation in your body, improving your overall immunity.
Jen Thomas is a Chennai-based weight-loss coach