Why Antioxidants Are Essential For Asthmatics

A healthy diet is vital for everyone, not just asthmatics, and eating right can protect you from high blood pressure, cancer, high cholesterol, allergies, and a host of other ills. Diet does this primarily by supplying the body with vital nutrients that permit normal function and boost the immune system. More important for asthmatics, a healthy diet provides an ample supply of antioxidants, critical weapons against the oxidative stress that is in part responsible for initiating the asthma cascade.

 

Some studies even point to dietary factors such as inadequate antioxidant intake for the increasing incidence of asthma. In one British study examining the effects of diet on asthma, the researchers state that "the observed reduction in antioxidant intake in the British diet over the last twenty-five years has been a factor in the increase in the prevalence of asthma over this period." The authors write that "populations of economically advanced countries have eaten a diet which has included less fresh fruit and vegetables and this diet has increased the susceptibility to potentially harmful, inhaled substances by reducing the antioxidant defenses of the lung against the effects of inhaled irritants and allergens." They conclude that diet has an important protective role to play in the prevention of bronchial reactivity. This sentiment is echoed by multiple studies that have concluded that people with asthma often have diets poor in antioxidants.

 

What exactly do we mean when we use the word "oxidation"? In nature, two basic types of chemical reactions occur: oxidation and reduction. Oxidation happens when a molecule loses electrons, whereas reduction occurs when a molecule gains electrons. When a molecule is oxidized, it becomes a free radical, a highly reactive and unstable molecule that can damage and kill the cells in your body. Free radicals are blamed for many of our most devastating diseases, including heart disease, diabetes, and asthma. If free radicals left us alone, we'd probably live a lot longer and wouldn't get very sick.

 

Because nature prefers stability, this unstable free radical attempts to regain its former stability by stealing electrons from another molecule, which itself then becomes an unstable and reactive free radical. This losing and gaining of electrons results in a chain reaction of multiple free radicals generating more free radicals. These oxidation-reduction chain reactions occur in our bodies every day and are usually well controlled by our own antioxidants, biochemical molecules that neutralize free radicals. In fact, a small amount of oxidative reactions are needed to protect our health, as free radicals are routinely employed by our immune system to kill microorganisms. Problems occur when our antioxidant forces are overwhelmed, allowing free radicals to wreak havoc on our tissues and organs, a condition known as oxidative stress.

 

While everyone would be better off if they could avoid oxidative stress, free radicals are a fact of life. The body's chief defenses against oxidative stress are antioxidants, which come in two primary forms: water soluble and fat soluble. Glutathione and vitamin C are two key water-soluble antioxidants; vitamin E and the carotenoids belong to the fat-soluble group.

 

Perhaps one of the easiest ways to understand oxidants and antioxidants is from the perspective of supply and demand. On the supply side, as we age our antioxidant reserves dwindle, permitting the ravages of aging and disease to take hold. Poor nutrition can also devastate our antioxidant defenses, since the body is heavily dependent on dietary sources of antioxidants. An unhealthy diet can deplete our antioxidant reserves, leading to oxidative damage and subsequent disease. On the demand side, anything that puts stress on the body can increase free radicals. This stress can be caused by a medical condition or environmental pollutants. In fact, environmental oxidative stress is now believed to be a leading contributor to the rising incidence of many diseases, including cancer.

 

Oxidative stress and antioxidants play a dramatic role in asthma. Asthma is a state of chronic airway inflammation, with inflammatory cells releasing free radicals that exacerbate the vicious cycle of asthma. Specifically, free radicals are blamed for bronchospasm, excess mucus production, and histamine release, all essential features of asthma. Not only do free radicals play a leading role in asthma, it appears that the free radicals produced by asthmatics are more toxic than those in people without asthma.

 

Without question, asthma is associated with an imbalance of free radicals that leads to increased oxidant stress. This is why the major emphasis of conventional medical therapy is directed at reducing inflammation and why, for better or worse, steroids are effective in treating asthma. From a natural-remedy perspective, this is why there is increasing interest in the role antioxidants play in the prevention and treatment of asthma. It is hoped that antioxidant nutrients and supplements can reduce inflammation without the potentially harmful side effects found with drugs.

 

In addition to protecting the body from internal oxidative stress, antioxidants play a major role in protecting the lungs from external harm. The United States has major air pollution problems, which many authorities believe are partly responsible for the current asthma epidemic. There are thousands of toxins released into the atmosphere daily, many of which can increase the lung's oxidative load, with the potential to exacerbate asthma. Building our antioxidant reserves can help prevent lung damage by attenuating this toxic insult.

 

For an asthmatic, the logic for boosting antioxidants goes like this: More antioxidants translate into fewer free radicals, which translates into reduced lung damage and irritation and fewer asthmatic symptoms. Supporting the role antioxidants play in fighting asthma are multiple studies that demonstrate impaired lung function in individuals who eat fewer fruits and vegetables, foods rich in natural antioxidants. One study of 2,650 European children, from the St. George's Hospital Medical School in London, examined the effect of fresh fruit consumption on FEV1 (Forced Expiratory Volume in One Second) and found that "FEV1 was positively associated with frequency of fresh fruit consumption." The study also reported that children who never ate fresh fruit had an estimated FEV1 that was 4.3 percent lower than those who ate fruit more than once daily. The authors concluded that fresh fruit appeared to be beneficial for lung function in children.

 

Other studies have linked low fruit consumption to poor lung function. One study from England examined the effect of fruit and fruit juice consumption on lung function in nearly 3,000 adults, ages eighteen to sixty-nine. The researchers found that the mean FEV1 among those who never drank fresh fruit juice and ate fresh fruit less than once a week was significantly lower than among those who had higher levels of fruit consumption. The authors concluded that "these results support the hypothesis of an association between infrequent fruit or fruit juice consumption and impaired ventilatory function in adults."

 

Another group of researchers from the University of Auckland in New Zealand, examined data from fifty-three nations that participated in the International Study of Asthma and Allergies in Childhood (ISAAC). The researchers found that there was "a consistent pattern of decreases in the symptoms of wheeze (current and severe), allergic rhinoconjunctivitis, and atopic eczema, associated with increased consumption of calories from cereal and rice, protein from cereal and nuts, starch, as well as vegetables and vegetable nutrients." The authors concluded that if the average daily consumption of these foods increased, an important decrease in symptoms could be achieved. In other words, eat a healthy diet and your asthma symptoms will probably get better—simple as that!

 

Having established that diet, and especially antioxidants, play a major role in alleviating asthma and maintaining overall health, let's examine the impact foods have on how we breathe.