Synopsis
Book by LiebmannSmith Joan Egan Jacqueline
Extrait
Chapter One
Your Hair
The Long and the Short of It
Hair defines us like no other part of the human body. It conveys to others an enormous amount of information: our age, gender, ethnicity, social status, religious and other group affiliations, personal hygiene habits, and—last but not least—our state of health. Yet the assumptions some people make based on our hair may be as false as their eyelashes. We can cover the gray, making us appear years younger; cut our hair very short or let it grow very long, making it difficult to determine our gender; or straighten curly hair or curl straight hair, making our ethnicity anyone's guess. And by adopting the hairstyles of the rich and famous, we can look like we're to the manor born when we may be struggling to make (split) ends meet.
Hair is overflowing with sexual symbolism and cultural significance. People in many parts of the world routinely—if not religiously—cover or remove it. English barristers, for example, wear wigs in court. Muslim and Orthodox Jewish women are required to cover their heads. And not only do Buddhists and some Christian monks shave their heads, but skinheads do as well.
While we're busy sending messages to the outside world by covering, cropping, curling, or coloring our hair, we should also pay attention to the messages it's sending us. Our untouched, natural hair can give us a headful of vital information that we should carefully read and heed. Your age, sex, and race, as well as where you live and the hair products you use, all affect your hair's mineral makeup.
Hair contains a myriad of minerals, from aluminum to zinc, and for many years hair analysis has been used to confirm mercury and arsenic poisoning. More recently, researchers have been able to diagnose eating disorders from hair samples.
Indeed, the quality, quantity, and color of our hair can all be signs of our physical well-being. No wonder hair is said to be a barometer of health.
Starting at the top
Hair texture changes
Hair is made up mostly of dead protein (keratin), but that doesn't mean it's supposed to lie there listlessly. Dry, brittle hair and split ends can all be signs that you're mistreating your hair with excessive washing, brushing, drying, dyeing, or bleaching. However, these hair shaft disorders, as they're called, can also be signs of stress, hormonal changes, nutritional deficiencies, and thyroid disease.
If you notice, for example, that your formerly luxuriant locks tangle easily or have become dry, brittle, or coarse, don't be so quick to rush off and buy the latest expensive new hair product. You may, in fact, have the classic signs of hypothyroidism—a fairly common but often underdiagnosed condition, especially among women. (See Appendix I.) When the thyroid gland, which regulates metabolism, fails to produce enough thyroid hormone, hair growth—as well as other body functions—slows down. Hair texture change can signal iodine deficiency as well, which is also implicated in thyroid disease. (See Chapter 6.)
Of course, texture changes may merely be an indicator of the natural hormone changes of pregnancy or menopause. During pregnancy, dry hair may become oilier or shinier, while oily hair can become drier and duller. Previously curly hair may become straighter and straight hair curlier. Hair may even become thicker, but this is due to the slowing down of normal hair loss that typically occurs in pregnancy rather than the thickening of individual hairs. (See Hair Loss in Women, below.)
During menopause, when estrogen levels drop, many women notice that their hair lacks softness and luster. The estrogen loss can cause hair shafts to thin and dry out, so new hairs will be duller and less manageable. New hair growth also tapers off
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Both hair texture change and hair loss are also common reactions to chemotherapy or radiation treatment for cancer. The good news is that both these changes are usually temporary.
Hair color changes
Hair color, like eye and skin color, depends primarily on how much melanin (color-producing pigments) we inherit from our parents.
If your hair color changes and you haven't been hitting the bleach or hair dye bottle, it can be a sign of a variety of factors, both internal and external. For example, hair color—like hair texture—can change temporarily after chemotherapy. A blonde may become dismayed to find her hair growing in dark brown or black, while a former brunette may be thrilled to find that she's become a blonde. Hair color changes can also signal genetic, metabolic, nutritional, or other disorders. They can even be the result of environmental factors.
Green Hair
Many of us look forward to our hair getting lighter from the summer sun. But if your hair looks more green than platinum, it's not the sun's fault. It's more likely to be a tip-off that your swimming pool is heavily chlorinated, or that copper from water pipes is seeping into your pool water. In fact, green hair used to be fairly common among copper- and brassworkers.
If you haven't been swimming lately, your sea-green hair can be a sign that you enjoy bathing in a tub that's been cleaned with chlorine-containing products. If your green hair doesn't seem related to swimming or bathing, it could be a more serious sign of excess exposure to mercury, which can cause neurological, muscular, sensory, and cognitive damage.
Striped Hair
Green hair may be medically unimportant, but striped hair is not. Known as the flag sign, the striped hair is actually bands of discolored or depigmented hair. The stripes—usually blond, gray, or reddish—are often red flags for severe nutritional deficiencies, for example, of protein or iron. Although much more common in underdeveloped countries, the flag sign can be seen in children living in poverty throughout the world.
Striped hair can also signal ulcerative colitis or other conditions or events that deplete protein, such as irritable bowel syndrome (see Chapter 8) or extensive bowel surgery. It might also be a telltale sign of the eating disorder anorexia nervosa, which depletes a person's protein supply.
Prematurely Gray Hair
When most people's hair turns gray, it's usually a normal—albeit not very welcome—sign of aging. As we age, we produce less melanin, the pigment that gives our hair and skin its color. But when your hair turns gray before its time, it can be a harmless, hereditary condition—or a warning sign that something is wrong. The definition of premature graying—medically known as canities—varies among doctors. Some define it as having half a head of gray hair by age 40; others say it's the graying of hair before the age of 20 in whites and before 30 in blacks.
Some people with prematurely gray hair may unknowingly suffer from pernicious anemia, a severe form of anemia in which there is a reduction of red blood cells caused by the body's inability to absorb vitamin B12. Pernicious anemia is commonly found in older adults. Other common signs of pernicious anemia include paleness, weakness, mouth and tongue problems, tingling and numbness in hands and feet, and an unsteady gait. If untreated, it can cause serious gastrointestinal or neurological problems. The good news is that not only is it treated easily, but hair often returns to its natural color.
Early graying can also signal various autoimmune disorders, including Graves' disease, the most common form of hyperthyroidism (see Appendix I). A recent Irish study has identified prematurely gray hair as a sign of low bone mineral density (osteopenia) in women with Graves' disease. Another autoimmune disorder signaled by premature graying, as well as by white patches on the skin, is vitiligo, (see Chapter 9), which is a benign condition. However, 1 in 3 people with vitiligo also suffers from thyroid disease.
Another autoimmune condition, alopecia areata, which is characterized by patchy hair loss, is sometimes spotted in young people with gray hair. (See Spotty or Patchy Hair Loss, below.)
There is also some disquieting new evidence that prematurely gray hair can be an early warning sign of diabetes, coronary heart disease (CHD), and an increased risk of heart attack (myocardial infarction).
Many people think having prematurely gray hair is a sign of stress, and there's some truth to this. One theory is that stress can precipitate autoimmune diseases or the other conditions mentioned above that can cause graying.
Hair Turning White Overnight
While stress may play a role in turning your hair gray, it can't do it overnight. Marie Antoinette's and Sir Thomas More's hair were said to have turned completely white the night before they were beheaded. Despite these and other historical anecdotes, no medical evidence exists that hair can turn white or gray so quickly. Once hair is produced in the hair follicles, individual hairs can't change color. The root of these anecdotes may be diffuse alopecia areata, a condition that is sometimes triggered by stress and causes a lot of hair to fall out very quickly. (See Hair Shedding, below.) If a person with a mixture of gray and pigmented hairs has this condition, the pigmented hairs are the most likely to be shed, leaving behind only the gray or white hair.
Losing it
Our head hair grows about half an inch per month. About 90% of our hair is in this growing (anagen) phase at any one time, which can last from two to six years. The rest is in the resting (telogen) phase, which lasts about two to three months. Then it falls out. On average, our scalps drop about 50 to 100 hairs each day. The exact number usually depends on factors we can't control—heredity, age, gender, and ethnicity. Whether it falls out in clumps or gradually, most of us will experience some hair loss over the course of our lifetimes. By age 50, more than half of women will have lost some locks. But the news is even worse for men. Fully 75% will h...
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