Colds and Flu Introduction

:colds.jpg The common cold and flu are types of upper respiratory tract infections that occur yearly, mainly during the fall and winter seasons. Both conditions are caused by viruses and are associated with decreases immunological functioning. The causative agent in 30-50% of cases of the common cold is one of the many types of rhinovirus. Echovirus, coxsackievirus and other viruses, account for the remainder of reported cold and flu cases. The viruses that cause the flu are influenza viruses, which are members of the orthomyxovirus family.

Although the same viruses cause the highly publicized yearly flu outbreaks, these viruses are subject to changes in their genetic structure, also known as antigenic drift. Antigenic drift results in the creation of new vaccine every year. Occasionally, there are major changes in the genetic structure of the flu virus. This is known as antigenic shift. This mutation can result in flu pandemics that have major effects on the overall state of health around the world. [1]

Symptoms of Colds or Flu

While the cold and flu are similar illnesses, there are a few important differences between the two. In general, a patient with a cold will usually exhibit general malaise (feeling sick), fever headache, and congestion. The nasal discharge in a common cold is watery and later becomes thicker and possibly purulent. The throat may also feel dry and scratchy, as well as red and irritated. In stark contrast, the symptoms of the flu tend to cause the patient to have more intense symptoms and will appear as if a “toxicity has occurred. Another feature of the flu as opposed to the common cold is that the flu will tend to occur in epidemics. A call to the local health department can help to determine if there is an active flu epidemic at any given time during an active flu season. [2] [3]

Conventional Treatment for Colds and Influenza

Diet and Lifestyle to help fight Colds and Influenza: The key feature in the treatment of Colds and Influenza is the strengthening of the immune system. There are several factors within the lifestyle of the individual that have been shown to have an impact on the strength of the immune system and its response to environmental challenges. The lifestyle parameters that have been studied with regard to their impact on the immune response time with Colds and Influenza include:

  • tobacco smoking
  • alcohol consumption
  • hours of sleep
  • physical exercise
  • eating breakfast
  • balanced nutrition
  • hours of work habits
  • mental stress

It was found that in individuals where the above parameters were rated as “good,” there was more NK cell activity, resulting in increased immune functioning. Although these results were measured to study lifestyle’s effects on cancer, it is easy to see that the immune system functions better when good lifestyle choices are made and applied. [4]

Adequate fluid intake helps fight Colds and Influenza: Maintaining good hydration is important for avoiding, as well as treating, a cold or influenza. The mucosa of the nasal passages acts as a barrier to pathogens. However, this barrier does not function well when the mucosal membrane is dehydrated. [5]

Avoid Simple Sugar: It is also thought that since Vitamin C and glucose (a simple sugar) have similar structures, that they might be in competition for entry into the cells of the immune system. Due to this, it is has been generally accepted that individuals avoid simple sugars as much as possible, especially during an illness. [6-7]

Moderate Stress reaction: There is significant evidence that the stress that we encounter in our lives, and how we react to a given stressor, has a great deal of influence on the function of the immune system. It has been found that people with higher levels of total stress tend to have more illnesses such as upper respiratory tract infections, including colds and influenza.

Therapeutically, it is useful to consider how one copes with the stressors in life. Taking time to gain perspective on these stressful situations and seeking support from friends, family, and professionals can help moderate an individuals reaction to normal everyday stress and acute stressors. [8-12]

Supplements helpful for Colds and Influenza

Vitamin C: Vitamin C is a well known antioxidant vitamin that is essential in humans; that is we are unable to manufacture this vitamin for ourselves and must consume Vitamin C through dietary sources. In its role as an antioxidant, vitamin C has the effect of quenching dangerous chemical reactions involving free radicals, that can damage cellular membranes as well as promote inflammation.

In the process of fighting infections, white blood cells use such free radicals to damage and kill bacteria, and virally infected cells. It is important that the chemicals that are used by the white blood cells to kill invaders are kept in check, otherwise health cells can be damaged and promote inflammation, which can ultimately worsen symptoms.

The use of vitamin C in the treatment of illness, specifically in the treatment of colds, has been somewhat controversial. This is, in large part, due to some scientific evidence that has been misinterpreted. The level of vitamin C that has been shown to be effective in the treatment of illness is 1-6 grams per day. It has also been demonstrated that this dose can reduce the duration of a cold by as much as 21%. It is recommended to get vitamin C from a supplement when ill, as juices tend to have high amounts of sugar which can interfere with the function of the immune system (see “Avoid Simple Sugar” section). [13-14]

Zinc: Zinc is an important nutrient for the overall function of the immune system and has shown antiviral activity as well. It is important that all nutrients be represented in someone’s diet to make sure that their immune systems are functioning properly, and zinc is no exception.

The most popular form for supplementation of zinc for the common cold is in lozenges. Since zinc lozenges for the treatment of colds have become popular, there has been an explosion of such products on the market. However, not all zinc lozenges are created equally. In some of the original research, there were studies that demonstrated that zinc lozenges did not affect the duration or severity of cold symptoms. The reason for this discrepancy is due to the individual manufacturer.

The form of zinc used, as well as the other ingredients used in the manufacturing of the lozenge, are important factors in determining the effectiveness of the product. It seems that in order for zinc lozenges to have their beneficial effect, the zinc in the lozenge must ionize in the in the saliva of the patient. Lozenges used should contain 13-23 milligrams of zinc in the form of zinc gluconate. Products should also be free of citric acid, mannitol, and sorbitol, all of which can interfere with the benefits of the zinc.

Patients using zinc lozenges recovered from their colds in an average of 4.4 days, as opposed to 7.6 days in the control group. There were also significant improvements in other measures of symptoms during the cold, such as; cough, headache, hoarseness, congestion, runny nose, and sore throat. [15-18]

Echinacea: Echinacea is a member of the daisy family of plants, and has been used for many years as a traditional treatment for the common cold and other immune-related ailments. Over 300 studies regarding the effectiveness of Echinacea and Echinacea preparations have been conducted, making it one of the most etensively studied herbs in the world. Echinacea preparations have demonstrated an ability to modulate various parameters of the human immune system, including numbers and activity of NK cells and monocytes, which are indicators of nonspecific immunity.

The body of scientific research that has been accumulated is somewhat contradictory. For as many studies that support the effectiveness of Echinacea, the same amount of studies seems to disprove its effectiveness. There are several possible reasons for this apparent lack of consistency: different species of Echinacea may have varying effects, researchers may not be using the correct parts of the herb, the herb may have been harvested improperly, or the herb may have been administered improperly.

In the studies that support the use of Echinacea, the herb has been shown to have a variety of preventative properties. Supportive studies conclude that Echinacea is a valuable agent in the standardized treatments for common colds, as well as other viral illnesses such as the flu. [19-23]


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