by Неизвестный
3 A wide range of human subjects has been studied to evaluate sperm counts and sperm motility. And whether you’re looking at men facing
final exams, running a race, or simply experiencing the stress of fertility testing, anxiety has a profound effect on sperm quality.228–229, 230, 231, 232, 233 Motility (normal movement), sperm counts, and sperm morphology (size and shape) all suffer when men are stressed, and, as we have well established, one of the most reliable anxiety-producing influences in a man’s life is caffeine.
PERHAPS MEN ARE NOT SO DIFFERENT AFTER ALL
We all want a healthy sex life for as long as possible. Men are often seen as being less willing than women to alter dietary habits and incorporate new healthy lifestyle habits. But if something simple like reducing caffeine consumption can keep us sexually vital and healthy, most men would choose to alter their diet any day over the pain of disease and the possible adverse effects of medical intervention.
The problem is that men often fail to recognize approaching danger until obvious symptoms send them to their doctor. And doctors are more likely to write prescriptions than provide dietary advice. So the issue becomes one of developing an increased sensitivity to the changes that occur in our bodies as we age, including the urinary pressure and delay that signals early prostate problems.
Clearly, caffeine affects women’s reproductive capabilities, and we know that caffeine produces stress that can affect male sperm quality. If you are a prospective father, it certainly seems prudent to err on the side of caution and join your wife in eliminating caffeine from your diet.
GOUT. OH, MY ACHING FEET
Gout is a painful condition (considered a type of arthritis) that results from the deposition of uric acid crystals in cartilage, the bones of the foot, and kidneys.
For unknown reasons, gout is primarily a male disorder, with only about 5
percent of patients being women.
There are a number of causes, mostly related to defects in uric acid metabolism, and these defects appear to be primarily genetic. As is almost always the case, however, heredity only predisposes one to the condition.
Dietary and environmental factors play an important role. Diets high in sugar
and protein have been shown to elevate uric acid levels,234 as can caffeine.
The caffeine connection is demonstrated by a recent case in which the patient, a fortyeight-year-old man, was “doing all the right things” to reduce his uric acid levels. He stopped drinking all alcoholic beverages, adopted a vegetarian diet, avoided sugar, and maintained ideal body weight. According to current medical knowledge, that was everything he could do. If he continued to experience gouty pain, he would have to take drugs to lower his uric acid levels.
At his wife’s prompting, he stopped drinking coffee, and in a matter of weeks, his pain was completely gone. That’s because one of the breakdown products of caffeine is methyluric acid, and that can add to the body’s uric acid burden.235 In fact, allopurinol, the drug that is used to treat gout, works by inhibiting the enzyme that converts methylxanthine (a caffeine metabolite) to methyluric acid.236
Now, besides an inherited tendency to accumulate uric acid, liver disease significantly increases the likelihood that caffeine will contribute to gout.237 If you remember that the liver is responsible for the entire chain of breakdown steps in the detoxification of caffeine, this is not surprising. What is surprising is that the elimination of caffeine is not (yet) a standard recommendation for individuals with gout.
Caffeine and Your Eyes
Consider the astonishingly complex series of events that is taking place right now as you read this book. The miracle of sight is an amazing process involving highly specialized cells held perfectly within a fluid-filled sphere. Sight is the richest of our senses, accounting for about 75 percent of all of our perceptions.
Often likened to a camera, the human eye is far more impressive. The “film,”
for example, can be used over and over again as long as the conditions are right for repair and regeneration. In fact, the retina can capture more than ten images a second throughout life, sending information through the optic nerve directly to the brain.
In fact, every structure of the eye is under constant repair, nourished by extremely fine blood vessels and a fluid known as aqueous humor. The flow of aqueous humor maintains the internal or intraocular pressure, and if this flow is impaired, pressure may increase, damaging the eye and leading to a condition known as glaucoma. Glaucoma is a major cause of blindness, affecting approximately 3 million Americans, and fully one-third of them don’t know they have the disease.
Caffeine significantly increases intraocular pressure in most people, especially when consumed in amounts of four or more cups a day.238 If you have glaucoma, this pressure increase can occur at half that amount.239 Experts believe that this results from changes in aqueous humor flow, and studies have shown a remarkable difference in the fluid dynamics of the eye between volunteers given caffeine and those given placebo.240
Perhaps even more serious (because it affects a greater number of people) is the decrease in microcirculation in the eye caused by caffeine. Here again, as in the brain and peripheral blood vessels, caffeine causes a marked constriction that limits the delivery of oxygen and vital nutrients to these tissues. Animal experiments show that this can inhibit the growth and repair of the lens of the eye.241 Studies with human volunteers illustrate that caffeine’s vasoconstrictive effect markedly reduces circulation to the macula, the central portion of the retina.242 Macular degeneration is the leading cause of vision loss and blind ness in people over sixty-five, with more than 16,000 new cases reported annually in the United States.243 What’s more, evidence suggests that the incidence of this condition is increasing rapidly.244
I find it remarkable that so little attention has been paid to the role of caffeine
I find it remarkable that so little attention has been paid to the role of caffeine in eye health. Caffeine’s diuretic effect can make your eyes so dry that wearing contact lenses is uncomfortable or impossible. Caffeine contributes directly to the two leading causes of vision loss and blindness. Today, healthfood stores are filled with herbs, vitamins, and specialty products intended to decrease risk for macular degeneration, cataracts, and glaucoma, and yet no one is sounding the alarm regarding caffeine.
Antioxidants can help avert these common eye disorders by preventing freeradical damage to the lens, retina, and macula. Ginkgo biloba and bilberry herb also help by improving microcirculation. But none of these measures will have the best results if you continue to counter their salutary effects with caffeine.
CHAPTER 6
Caffeine and Women’s Health
The hardest years in a woman’s life are those between ten and seventy.
—HELEN HAYES (at eighty-three)
You’ve Come a Long Way
Women today are under a tremendous amount of pressure to balance the demands of family and career . Not that past generations of women had it easy—it’s simply that the pace of life, and therefore the stress of life, has accelerated to the breaking point. What’s more, women are facing these pressures alone, simply because the support systems of agrarian or tribal communities that were common centuries ago have largely disappeared.
In this book, I have tried to get across the equation that Caffeine = Stress.
This is a critically important message, but it is opposed by powerful propaganda from the caffeine industry. Caffeine products are advertised as a “pick-me-up,”
with no mention of the fact that just a short time later they become a “drag-medown.”
It’s always a surprise to me when I suggest that a patient cut back on caffeine and she reacts as though I’d asked her to betray her best friend. Even when I show her documented proof that caffeine is contributing to many (if not most) of her health disorders, she finds it hard to believe that her beloved coffee would do her harm.
With Friends Like These, Who Need
s Enemies?
Let’s face it. We all grew up with the idea that coffee was something you shared in special moments with a friend. This warm, fuzzy picture was conjured up by
in special moments with a friend. This warm, fuzzy picture was conjured up by Madison Avenue ad men to get you hooked on caffeine products. The advertisers know that if they can just get you to consume a few cups of coffee or a few soft drinks a day, you will turn into a lifelong addict.
To illustrate how well this campaign has worked, one need only look at women’s health literature. With very few exceptions, nothing is mentioned about eliminating caffeine, even though the connection between caffeine and women’s health is undeniable and extremely important. In Chapters 3, 4, and 5 we looked at caffeine’s contribution to a number of health disorders, including heart disease, digestive problems, diabetes, fibromyalgia, panic attacks, depression, and anxiety. This chapter will cover caffeine’s impact on issues specifically related to women, such as premenstrual syndrome (PMS), menopause, fibrocystic breast disease, iron absorption, calcium deficiency, osteoporosis, fertility and conception disorders, and complications of pregnancy and childbirth.
The Gender Gap
When it comes to evaluating the potential dangers of caffeine, gender is the most important consideration. Yet the entire issue is usually overlooked or ignored.
Compared to men, research shows that caffeine is much more damaging to women, producing adverse effects at lower intake. The effects are even more farreaching when you consider the harm caffeine does to fetuses and nursing babies.
Given these facts, you may be surprised (and dismayed) to learn that roughly 75 percent of the human research on caffeine has been conducted on men.
Hopefully, this chapter will serve to offset this astounding imbalance by describing exactly how caffeine affects women and what can be done to minimize the health risks associated with caffeine intake.
First of all, women detoxify coffee much more slowly than men. What’s more, the half-life of caffeine (the time it takes the body to eliminate one-half of a given dose) changes according to a woman’s menstrual cycle. In the luteal phase (roughly the last two weeks leading to menstruation), the half-life of a cup of coffee can be 7 hours, as compared to 5.5 hours in the follicular phase (the first two weeks of a woman’s cycle).1 Moreover, a number of factors specific to women, such as the use of birth control pills, reduce caffeine clearance even further. In fact, women on birth control pills require about twice the normal time to detoxify caffeine.2
All of this means that the cumulative effect of daily caffeine intake is very significant for women. A woman’s second (and even third) caffeinecontaining beverage will hit her glands, organs, and nervous system long before her body recovers from the first cup.
Caffeine just plain affects women differently than men, and it has to do with much more than the decreased clearance rate. In one study, for example, men and women were given the same 150-milligram dose of caffeine at the same time of day. The body temperature of the female subjects increased, while the male subjects experienced a decrease in temperature. In addition, an hour after caffeine administration, female subjects rated themselves as more sleepy, tired, and “disorganized” than the male subjects did, and on standard cognitive tasks, the female subjects found that caffeine made performance more difficult.3
Stress in general affects women more severely than men. Faced with threat or
conflict, research shows that women tend to have a much greater stress response compared to men, resulting in higher blood levels of stress hormones.4 This response does not mean that women are “weaker.” On the contrary, I believe it indicates that women tend to respond to conflict more seriously than their male counterparts.
And they suffer for it. In one three-year study evaluating the effects of stress, elevated cortisol not only increased risk for cardiovascular and other diseases, as it did in men, but in women the stress response also predicted a decline in memory as well as cognitive and physical functioning.5
The Stress Chain Reaction
When the level of stress hormones (especially cortisol) is elevated, many of the body’s maintenance and repair functions cease. How could it be otherwise?
After all, this stress response was originally intended to get us out of imminent danger. To mobilize all available energy for survival, Mother Nature devised a way to shut down all noncritical functions in order to send blood, nutrients, and oxygen to the heart and skeletal muscles.
As I mentioned in Chapter 4, few of us today ever face the kind of danger that requires explosive action. Our stresses are the smoldering, chronic stress of twentieth-century living and twentieth-century caffeine consumption. But even though the stresses are different, our bodies’ response is the same, and the shutdown of repair functions can weaken our bones, delay healing, and create lines and wrinkles in our skin. In short, caffeine and stress accelerate the aging process.
Phillip Gold, a researcher at the National Institutes of Mental Health in Bethesda, Maryland, compared the bone density of women with elevated cortisol to that of women with normal cortisol. Although all the women were age forty, those with elevated stress hormones had the bone density of seventy-year-olds.6
New Research Clarifies Heart Disease Risk
Remember how heart disease was once considered a “man’s disease”? For years, the vast majority of research was conducted on men. Then someone noticed that just as many women die of heart disease—however, for different reasons.
Apparently, women are more likely to have fatal heart attacks caused by coronary vasospasm, a constriction of the artery wall that shuts off blood flow to the heart.
The likelihood of coronary vasospasm is related to both stress and caffeine. A study examining the relationship between specific foods and the risk of heart attack in women found that the women who consumed the most coffee had nearly three times the risk of heart attack compared to women who drank the least amount of coffee. The association of caffeine and increased risk for heart attack was stronger than the risk factor for total fat added to food!7
In the United States, breast cancer claims the lives of approximately 44,000 women each year. At the same time, more
approximately 44,000 women each year. At the same time, more than 235,000 are killed by heart disease.
Job Stress and Caffeine Linked to Depression and Hostility Faced with overwhelming workloads from their families and their employers, women today are falling apart in record numbers. Instead of being part of the solution, caffeine is very much part of the problem. North Carolina researchers found that women who were overworked and experiencing high levels of stress scored significantly higher on standard tests measuring depression, anxiety, and hostility.8 In addition to the fact that such conditions are painful and reduce one’s quality of life, all of these factors increase the risk for cardiovascular disease.
Other researchers from the University of California found that highly stressed female attorneys who worked more than forty-five hours a week were three times more likely to have a miscarriage during their first trimester of pregnancy, compared with those who worked less than thirty-five hours a week.9 Again, caffeine, is a cofactor for two reasons: (1) People who work long hours have been shown to drink more caffeine; and (2) conclusive research has found a significant association between caffeine intake and miscarriage (see page 247).
Perhaps the new definition of “coffee break” should be “a break from coffee.” I encourage all of my female clients (actually, I implore them) to replace the caffeine with herbal coffee, herb tea, or another noncaffeinated beverage (see Appendix A, “Resources”).
Stress and Your Gastrointestinal Tract
It is well known that caffeine contributes significantly to anxiety, hostility, and depression. In turn, these are powerful risk factors for irritable bowel syndrome and ulcers (see Chapter 5). “Women with these characteristics [anxiety and hostility] were more than twice as likely to develop an ulcer,” reports D
r. Susan Levenstein, who headed an eight-year study regarding psychosocial influences on health.10 Women who were depressed at the start of the study were three times more likely to develop an ulcer over the study period.
A Little Dose’ll Do Ya
Keep in mind that the damage done to the body and mind by caffeine is very much dose-related. A little caffeine will do a little harm, while lots of caffeine will do lots of harm. Determining factors include:
1. Your age, weight, overall health, and current medications. Remember that birth control pills greatly reduce the liver’s ability to detoxify caffeine
2. Your sensitivity to caffeine. For unknown reasons, some people are simply more sensitive to caffeine than others. This may be related to allergy, body type, adrenal health, or other factors.
3. Your activity level after consuming caffeine. What do you do after you consume caffeine? If you exercise, you can to some extent “work off” the stress hormones, glucose, and fatty acids that were released into your bloodstream. But if you sit at a desk, the biochemical events resulting from caffeine consumption will result in wellunderstood and documented damage.
Caffeine Causes Serious Nutritional Deficiencies
Calcium deficiency, osteoporosis, and iron deficiency are three of the most common nutritional problems in America today—especially among women. At the same time, coffee, tea, and soft drinks are the beverages most often consumed with meals. It turns out that the relationship between these nutritional problems and caffeine consumption is very well established.
