Achoo! Food and Other "Prescriptions" for Surviving Cold and Flu Season

As cold weather sets in and the days become shorter, we have something else to look forward to: cold and flu season. As I write this article, I am doing my best to get over a nasty cold, so this article will discuss ways to prevent a cold, what to do during a cold, and things to do as you recover. But first things first.

Cold and flu season: What is it? What causes it?

Colds are most commonly caused by respiratory viruses called rhinoviruses, a word that stems from the Greek word for “nose.” Other common types of viruses that cause symptoms of a cold include coronaviruses, parainfluenza viruses, adenoviruses, enteroviruses, respiratory syncytial viruses, and influenza viruses.

Because many of these viruses mutate or change rapidly, and there are more than 200 different types of viruses that cause cold-like symptoms, it is evident why colds and the flu are extremely prevalent in the general population, especially among children and the elderly.

How can I protect myself against cold and flu season?

This brings me to vaccines, a topic that has received a ton of attention as of late, and a topic that I could write about for quite a while.

In relation to the common cold, there is no vaccine; however, there is a seasonal vaccine for the flu. The influenza vaccine is developed based on three to four circulating viruses that health professionals predict will cause infection in the general population. The seasonal influenza vaccine delivers inactivated viral proteins to prime specialized immune cells, i.e., the cells that fight off infection. If you become infected with the influenza strains found in the vaccine, then your immune system will be able to mount an appropriate and targeted response to prevent infection.

Because of frequent viral "shift and drift" (i.e., assortment and mutations), a yearly vaccine is required. Vaccine efficacy ranges each year, and its effectiveness can vary from 10 to 60 percent. Vaccine efficacy depends on a variety of factors, such as the similarity between the vaccine viruses and circulating viruses, as well as the age, health, and immune system of the person being vaccinated.

These numbers are not meant to discourage influenza vaccinations; rather, they are intended to encourage vaccination, as the influenza vaccine is the best way to prevent you and those around you from getting sick.

I got my vaccine but I want to do more. Is there anything I can do in terms of prevention?

Turns out, there is plenty you can be doing to protect yourself from getting the cold or flu. First up, wash your hands. Frequent hand-washing is a great way to prevent the spread of infection.

Next, make sure you are getting enough rest. Studies have shown that sleep dramatically impacts the immune system, and sleep deprivation decreases immune cell responses.

Moderate exercise also has been linked to stimulating specific immune cells. However, it is important to highlight that many of these studies investigated moderate levels of exercise and that endurance training has been shown to exert an opposite effect on the immune system.

What about food? Do dietary nutrients help protect against infection?

Dietary components can be especially helpful in keeping your immune system strong to protect against infection. It goes without saying that a balanced diet that incorporates fruits and vegetables is a great way for you to protect yourself against infection. But there are a few other things you can do to increase your protection. Let’s go through what works and what may not work so well.

First, vitamin C. You may have seen the wide swath of products on the market that advertise the importance of vitamin C during cold and flu season, but does increasing vitamin C intake actually help?

Turns out, the relationship between vitamin C and respiratory infections has been studied quite extensively. A thorough meta-analysis recently conducted for the Cochrane Library examined 29 trials with more than 11,000 study subjects enrolled in a supplementation study of 0.2g/day or more of vitamin C found that there was no evidence that vitamin C reduced the incidence or severity of the common cold. Because of this, taking large doses of vitamin C may not be the best remedy to prevent the cold or flu.

However, there are a few supplements that may protect against the common cold or influenza. As opposed to vitamin C, minerals such as zinc and antioxidants such as flavonoids possess potent anti-viral properties.

A double-blind, placebo-controlled trial using zinc lozenges revealed that zinc treatment significantly reduced clinical scores of a common cold infection. Furthermore, an intervention review on zinc treatment for the common cold was conducted for the Cochrane Library. Singh et al analyzed data from nearly 20 trials and more than 1,700 participants and found that zinc was associated with a significant reduction in the duration of common cold symptoms.

Flavonoids are nonessential antioxidants that occur naturally in many plant-based foods and possess profound effects on human health, such as decreasing excessive inflammation and regulating oxidative stress. More than 8,000 flavonoid compounds have been identified, and they can be broken down into six groups: flavonols, flavones, isoflavones, flavanones, anthocyanidins, and flavan-3-ols.

Flavan-3-ols found in green tea, such as epigallcatechin-3-gallate (EGCG), have been studied extensively in the context of influenza infections. Various studies have shown that EGCG inhibits viral replication using in vitro and animal models, suggesting that EGCG could protect against influenza infection in humans. Until then, we will have to wait to see what clinical trials reveal.

Hopefully, after reading this article, you won't be hit hard by cold and flu season and you will be healthy during these difficult months. So go get your vaccine, wash your hands often, get plenty of sleep and moderate exercise, and eat a balanced diet.

At the first sign of symptoms or if others around you start getting sick, take a zinc supplement and/or drink some green tea.