While it is well documented that avoiding germs helps prevent the spread of infections, the hygiene hypothesis suggests that we have taken this too far. And with the advent of antibiotics and the great public health efforts of the last century, the immune system is no longer required to fight germs as actively as in the past.
Scientists based this hypothesis in part on the observation that, before birth, the fetal immune system’s “default setting” is suppressed to prevent it from rejecting the mother’s tissue. This is necessary before birth—when the mother is providing the fetus with her own antibodies. After birth the child’s own immune system must take over and learn how to fend for itself. But the extremely clean household environments often found in the developed world do not provide the necessary exposure to germs required to “educate” the immune system so that it can learn to launch its defense responses to infectious organisms.
A critical part of this evolution is orchestrated by a child’s developing microbiome, and a lack of diversity—reduced by exposure to fewer germs and infections—derails the period of immune growth after birth.
The hygiene hypothesis has been implicated in the growing number of people with allergies, autism, and autoimmune diseases.
MacDonald’s Farm Had the Right Idea?
Since the hypothesis was first proposed by epidemiologist Dr. David Strachan in 1989, several studies have revealed a reduction in the sensitivity to allergens and atopic (skin) disease in children exposed to farm environments, those who have animals in their homes, and in those who have attended day care at an early age and were exposed to other children’s infections.
Several lessons have come from studies comparing populations in Russian Karelia and neighboring Finland. These two populations live in completely different socioeconomic circumstances—they have one of the largest socioeconomic discrepancies in the world—yet share similar diets and genetic backgrounds.
The researchers determined that the children in Karelia are exposed to a large variety of different microbial infections that are significantly less frequent in Finnish children. Starting in 1999, numerous studies on autoimmune and allergic diseases show an incidence of type 1 diabetes that is six times lower in Russian Karelia. The incidence of celiac disease is 1 in 496 in Karelia and 1 in 107 in Finland using identical criteria. These studies appear to indicate that environmental factors play a role in our immune reaction to microbes and in the development of allergies and autoimmune conditions. While all of the factors initiating these conditions have not been identified, the hygiene hypothesis offers an intriguing approach.
The mechanisms by which microbes can reduce the development of autoimmune disease are not well understood. They are only part of a larger autoimmune and allergic response that is also affected by your genetic makeup, and a variety of factors that occur over a person’s lifetime. It cannot be considered the sole determinant of a disease.
Before people start feeding their children from the floor or allowing them to share the dog’s bowl, it should be stressed that many researchers feel that the hygiene hypothesis is far too simplistic an approach to understanding the causes of celiac disease or any other autoimmune disease.
This hypothesis does focus attention on the impact of microbes on disease, hopefully without discouraging good hygiene practices.
BOTH ORTHOREXIA AND the hygiene hypothesis are extreme examples, yet they illustrate what can happen when individuals become mesmerized by the message, and the human body is deprived of the many forms of nourishment it requires to develop, grow, and flourish. Both advanced in the name of “health.”
What we deprive our body of is every bit as important as what we feed it.
Pitfalls and Perils of a Gluten-Free Diet
Sooner or later everyone sits down to a banquet of consequences.
—R. L. STEVENSON
A gluten-free diet gives with one hand and takes away with the other. For individuals with celiac disease, it truly is a lifesaver yet requires constant vigilance and restrictions. Others find it gives them relief from symptoms like gas and bloating while taking many essential nutrients from their diets. The “giving hand” can also contain heavy metals, toxins, and excess fat and sugar. The “taking hand” dips into pocketbooks for more costly foods. The scale can get very unbalanced if individuals are not aware of the health risks in a gluten-free diet that are often hidden behind the hype surrounding it.
Studies on the real long-term effects of a gluten-free diet on the body and the brain are being published with increasing regularity since the awareness of celiac disease and popularity of the diet in the general public began about a decade ago. While many of the studies are on celiac disease patients who must follow a strict gluten-free diet, research has exposed some troubling issues that affect everyone following the diet.
Mostly we are doing it because we realized how good we can feel and believe it is healthy for us.
(ARIELLE, 33)
A gluten-free diet is many things to many people, but for most it is far from healthy.
Healthy or Hazardous?
Nutrition
Going “gluten-free” may cure symptoms for some, and is a necessity for those with celiac disease, but eliminating gluten from your diet also removes much of the fiber and some essential vitamins and minerals from your food supply.
Wheat, rye, and barley are flavorful, vitamin-and fiber-filled grains. Ironically, manufacturers also regularly fortify wheat flours as well as the cereals, breads, and other processed products made from them with the vitamins and minerals that might have been removed during processing. Conversely, gluten-free foods, with a few exceptions, have not caught up with this fortification. Some, like quinoa, may not need this as much as rice flour.
The breads, cereals, cookies, cakes, and snacks with gluten-free grains also put people at risk for potential problems with excess fat, sugar, and salt. These ingredients are used to bind gluten-free products—gluten is the “glue” that holds breads and cakes together—and to make them as tasty as their wheat-filled counterparts.
People with celiac disease who embark on a gluten-free diet without the help of a nutritionist can easily develop vitamin and mineral deficiencies, especially iron and the B vitamins. Calcium can also be deficient if dairy is restricted. This is a double problem because many start the diet already suffering from malabsorption due to the damage to their small intestine. Missing a favorite sweet or breaded dish, they often make poor food choices to satisfy a craving.
Lost fiber and nutrients need to be replaced with fresh fruits, nuts, beans, vegetables, and other gluten-free grains (e.g., quinoa, millet, buckwheat, sorghum) to maintain a “nutritional” diet. If you are going to take gluten out, put its nutritional value back in. (For more, See chapter 31, “Eating Healthy.”)
Heavy Metal (Not of the Musical Variety)
Rice, a common substitute in a gluten-free diet, may contain high levels of arsenic as well as cadmium and mercury. Other heavy metals (e.g., tin, lead, and mercury) have also been found both in gluten-free food and flours and the people ingesting them.
While the raised levels do not approach toxic levels,