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Using Echinacea to Treat Colds


The echinacea flower has long been associated with cold treatment.
The echinacea flower has long been associated with cold treatment.
©iStockphoto/Thinkstock

When it comes to fighting nonviral infections, echinacea -- an herbal treatment and natural home remedy option -- is usually no substitute for punch-packing pharmaceutical antibiotics. But research does support echinacea's effectiveness for some viral infections -- such as the cold and flu -- because it significantly boosts your body's immune system and helps you to heal faster than you otherwise might.

Compared with some other herbal treatments, we know quite a bit about how echinacea works. In the past 35 years, more than 200 scientific studies have been conducted to determine the herb's safety and efficacy.

How Echinacea Works

Echinacea appears to boost the body's immune response. Unlike a vaccine, which is active only against specific invaders, echinacea stimulates overall activity of cells responsible for fighting any infection that exists in your body.

Unlike antibiotics, which simply kill bacteria, echinacea stimulates the body, at a cellular level, to fight off bacteria, viruses, and other pathogens. In other words, echinacea tells your body to heal itself.

Early on, researchers determined that echinacea has a profound effect on the number and kind of blood cells in the bloodstream. Echinacea works by promoting the production of white blood cells when the percentage is too low and helps them get to where they can fight the infection more effectively.

The main active compounds in echinacea are complicated and fall into several categories. Complicating matters is the fact that there are some differences among the three main species of echinacea used. There is no single "magic bullet" chemical that explains how echinacea works -- it is a combination of many ingredients.

Some of echinacea's chemical constituents also appear to be involved in regrowth of connective tissue that has been destroyed during infection, an action that greatly stimulates the healing process.

When germs get into your bloodstream, they stimulate an enzyme called hyaluronidase to break down the connective tissue surrounding cells. Once these connective tissues have been compromised, germs can easily latch onto the cells and begin the progressive cellular destruction known as infection. But studies in Eastern Europe in the 1960s found that echinacea neutralizes hyaluronidase, so the germs can't get a cellular foothold.

Echinacea also helps your body to produce natural infection-fighting chemicals. Your spleen, liver, and lymph nodes contain large white blood cells called macrophages, which filter lymphatic fluid and blood and engulf and destroy bacteria, cellular debris, and other foreign particles in a process called phagocytosis.

Before a virus-­infected cell dies, it releases a small amount of interferon, which boosts the ability of surrounding cells to resist infection. Echinacea stimulates macrophages to produce interferon and other immune-enhancing compounds, including interleukins, and tumor necrosis factor, which then fight off infections that cause colds, flu, respiratory and urinary tract illness, and other conditions.

The most consistently proven effect of echinacea is in stimulating a process called phagocytosis, which encourages white blood cells to attack invading organisms. Learn more on the next page.


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