Diet and The Menstrual Cycle - The Link
Ask any grandparent about their grandchildren and they are likely to mention “how fast they grow up.” A young person today will witness more technological and cultural changes before high school graduation than older generations did in an entire lifetime. And, while sweeping technological advances are changing how much of the world communicates, works, and travels, they are also dramatically altering how foods end up on our plates. In North America, meals at home have been replaced by fast food, and snack food is now everywhere. In Asia, similar influences have allowed an influx of burgers, chicken, and hot dogs to replace traditional rice, noodle, and vegetable dishes. Our bodies, and now theirs, have been hard pressed to cope. The dangers of growing up on fatty, meaty, over processed convenience foods are now very clear as heart disease, cancer, diabetes, high blood pressure, and many other illnesses have become epidemics. But there are more subtle changes, too—biological effects of unhealthy diets—that occur surprisingly early in life. The majority of girls in Western nations reach puberty at about 121⁄2 years of age. Half of British girls are now showing signs of puberty by age 8. It wasn’t always so. World Health Organization records show that in 1850, the average age of menarche (the first menstrual period) was about 17. Over the past 150 years, it has slowly but steadily fallen. The reason for the decline appears to be gradual changes in our diets. Highly refined and processed foods have edged out vegetables and fruits. Meat and dairy products have taken centre stage in many meals—even breakfast. Time and again, when various regions of the globe become Westernized, traditional foods made of whole grains, vegetables, and beans are abandoned in favour of cheeseburgers, chicken “strips,” and greasy fries. In the process, dietary fat skyrockets and healthy fibre and vitamins are lost. As we will see, these diet changes increase the amount of sex hormones in a child’s bloodstream and, with their hormones unnaturally elevated, girls and boys reach puberty earlier in life. Besides the emotional and societal challenges that early sexual maturity brings, it can have lasting effects on our health—especially for women.
Later we will see how the factors that drive early puberty also can lead to a more difficult menopause and even an increased risk for breast cancer. But first let’s see how foods affect a woman’s basic hormonal cycle. You may not think about it until the week before your period begins, but the hormones in your body are constantly in flux. Your ovaries make several kinds of estrogens (although for simplicity we will refer to them collectively as estrogens) and progesterone, each of these sex hormones playing a unique role in reproductive functions. For British women, an average menstrual cycle lasts about twenty-eight days. At the beginning of each cycle, estrogens levels slowly rise, causing the lining of the uterus to thicken in preparation for pregnancy. In about two weeks, as estrogens drops, an ovary releases an egg, which passes into the fallopian tube and then into the uterus. Along the way, fertilization can take place. Taking over where estrogens left off, the ovary then starts to manufacture progesterone, the “pregnancy promoter.”
The Hormonal Cycle
Progesterone signals the walls of the uterus to fill with blood vessels to nourish a growing baby. If the egg is fertilized, the ovary keeps on making progesterone. If not, production is halted and the lining of the uterus is shed (menstruation). These hormones have many other functions, too. Estrogens is responsible for the changes that occur in girls at puberty, and both estrogens and progesterone influence bone strength.
Foods That Calm Hormonal Tides
The foods we eat have a dramatic effect on these hormonal cycles. Foods you may have grown up eating—meats, cheese, eggs—easily drive hormonal levels up. Just as fatty foods make your cholesterol level rise, they do the same to your estrogens level. And, the more fat you have in your diet, the higher these estrogens go. This happens with all kinds of fat whether if comes from meat, dairy products, or from oils used in cooking. So as estrogens levels begin to rise with the start of each menstrual cycle, fatty food causes them to rise more steeply and to reach higher levels in your bloodstream. In the days before your period, oestrogen levels finally drop. How far they have to drop depends on how high they were to begin with. On a high-fat diet, the drop from an artificially high level and back down again will be sharper. This “estrogens withdrawal” can cause a variety of problems, from painful periods to difficult menopause. In populations where more traditional, plant-based diets are still regularly consumed, women have lower oestrogen levels and longer menstrual cycles—that is, a longer time between each menstrual period. This means they have less exposure to oestrogen hormones throughout life and an easier time with many hormone-related changes—simply from dining on hearty breads; rich bean, pea, and lentil dishes; and plenty of vegetables.The best way for a woman to calm hormonal shifts is to the foods that cause them. Exchanging fatty foods for natural plant foods—more whole grain bread, pasta, and cereal, a variety of vegetables, fruits, and legumes—prevents estrogens levels from entering the danger zone. The advantage of these foods comes not only from being lower in fat, important as that is. The key ingredient in these foods, as physician Denis Burkett established in his ground-breaking research, is fibre. Foods from plant sources contain an abundance of natural fibre, which is completely missing from animal sources. Practicing surgery in Africa for more than twenty years, Burkitt questioned why certain diseases, so common in America and Europe, were rarely seen in less developed nations. His research showed that the dramatically lower rates of colon, rectal, and breast cancer he saw in his patients were partly due to the amount of fibre and lack of fat in their diets. Here’s what he found: After each meal, bile acids in the intestines go to work to absorb fat. Bacteria in the intestines turn some of them into cancer-promoting secondary bile acids. When there is plenty of fibre, less of these acids turn dangerous, while at the same time excess acids are soaked up. Fibre also sweeps away cholesterol. These findings held the promise of dramatically cutting cancer and heart disease rates, and Dr. Burkitt and his colleagues became deservedly famous in the medical community.
But it turns out that the very same process works to rid your body of excess estrogens. These estrogens are filtered out of the bloodstream by the liver, passed down through a tiny tube called the bile duct, into the intestinal tract, where fibre carries them away. In a Dutch study, researchers observed the eating habits of young girls and measured the hormones in their blood. They found that those who consumed more vegetables and grains had lower oestrogen levels and reached puberty later in life. The girls who ate more vegetables got about 20 grams of fibre per day, just slightly more than the other group, though it was enough to delay puberty. This means a lower risk of any of the problems caused by excess estrogens, including cancer, in the future. When you consider how much fibre a total vegetarian menu provides—30 to 40 grams per day—you can imagine what it does to smooth out hormonal surges. Plant foods protect in three powerful ways. First, they drastically reduce the amount of fat in your diet. According to the National Cancer Institute, cutting your fat intake in half will lower your oestrogen levels by about 17 percent. Second, the fibre in plant foods naturally helps your body get rid of excess hormones. Third, plant-based diets increase the amount of sex-hormone binding globulin (SHBG) in the blood. These special protein molecules hold on to oestrogen and testosterone until they are needed. They keep hormones in check, promoting a more stable menstrual cycle and reducing cancer risk. Studies have shown that, in men, having more SHBG in the blood can mean a less aggressive and domineering personality—not a bad side effect. The table on the following page compares the amount of fat in a variety of animal products and plant foods. It’s easy to cut the fat in your diet simply by switching the type of foods you eat, rather than reducing portions. As you can see, plant foods are usually very low in fat. There are a few exceptions, such as avocados, nuts, olives, seeds, and tofu. They are fine for occasional use, and contain valuable nutrients of their own, but you’ll want to keep them to a minimum to maintain a very low-fat diet.
Premenstrual Syndrome—Causes and Cures
If you don’t pay close attention, the only connection you may make between hormonal changes and the foods you eat is the candy bar craving that comes during the week before your period. Of course, there is more to premenstrual syndrome (PMS) than food cravings. In fact, PMS can encompass many symptoms—up to 150 as recorded by researchers—ranging from mild to debilitating, depending on the individual.PMS affects approximately 40 percent of women of childbearing age, but has come under serious scientific scrutiny only in the past three decades. The most common symptoms can include breast tenderness, bloating, backache, headache, irritability, nausea, depression, acne, and reduced concentration. Not surprisingly, diet has a lot to do with it. As we have seen, the hormone shifts that lead to PMS can be dramatically affected by how much fat and fibre are in the diet. Cutting the fat reduces hormone shifts, and increasing fibre helps eliminate excess hormones.Putting vegetarian foods to the test, doctors at the Physicians Committee for Responsible Medicine and Georgetown University conducted a study examining the effect of diet on PMS and menstrual pain. For two months, participants were asked to eat a low-fat vegan diet (containing no animal products) of vegetables, grains, fruits, and legumes, with no restriction on quantity.Many participants in the vegan diet group were delighted to find a reduction in both the duration and the intensity of menstrual pain. Many also found relief from the concentration problems, constriction of social and work interactions, and water retention that come along with PMS. Women in this group also lost an average of one pound per week.How do foods affect menstrual pain? The painful cramping in the uterine muscles comes from prostaglandins, chemicals made from traces of fat stored in cell membranes. The researchers hypothesized that if women reduced their fat consumption, they would in turn decrease their oestrogen levels, which would reduce cell growth and prostaglandin production in the uterine lining. The goal was to use foods that even out the hormonal highs and lows many women experience each month. And it worked. For many, the change was so profound that they were reluctant to return to their old eating habits later, even when the researchers asked them to. They had less pain, more energy, and lost weight—and they wanted to stay that way.
Other Factors Affecting PMS
Other aspects of your diet can affect how you feel throughout your menstrual cycle. Let’s look at current findings on certain food ingredients, medications, and natural remedies you may not have considered.
There is evidence that getting into better calcium balance can ease menstrual pain, especially milder varieties. In one study, calcium carbonate supplements (1,000 mg per day) reduced both menstrual pain and PMS symptoms. A combination of calcium and magnesium also reduced pain and premenstrual water retention while improving mood and concentration. It is important to remember, however, that attaining ideal calcium balance is not just a matter of adding more calcium, but also keeping the calcium you have. Animal proteins force your kidneys to remove too much calcium from the blood and excrete it in the urine. By keeping animal products out of your diet, you can cut your calcium losses in half. By including green, leafy vegetables, beans, lentils, and other calcium-rich plant foods and fortified orange juice in your diet, you will ensure that you get plenty of calcium and that it stays where it belongs. It is best to avoid getting calcium from dairy sources because of the significant animal protein and sodium load they provide, which serves to deplete much of the calcium they contribute. And surprisingly enough, only 30 percent of the calcium they contain is readily absorbed in your body. Most vegetables and beans have plenty of low-fat, highly absorbable calcium. Magnesium-rich foods such as soybeans, beet greens, black-eyed peas, and tofu aid calcium absorption even further.
Many vegetarian foods and Asian specialties made from soy such as miso soup, tofu, and tempeh contain weak plant oestrogen called phytoestrogens. These natural plant estrogens provide benefits in two important ways. First, they attach to the oestrogen receptors on your cells, preventing much of your own oestrogen from doing so, therefore preventing unwanted activity on the cell. Less oestrogen activity can mean a reduction in menstrual symptoms, as we have seen, and also reduces the odds that cells will turn cancerous.Interestingly, phytoestrogens have the opposite effect for women after menopause. When your natural oestrogen production wanes, plant estrogens may help to bolster it, reducing hot flashes and other menopausal symptoms. In essence, soy foods and vegetarian foods work as a sort of “oestrogen regulator” throughout life, helping to make each hormonal change easier.
Caffeinated coffee, teas, and sodas are popular pick-me-up beverages, but they also can aggravate PMS symptoms. Many women who eliminate caffeine from their diets find relief. Trading soda for water also can help reduce bloating and prevent dehydration, which can cause fatigue and mental sluggishness.
If you are reaching for sugar-filled candy bars and cookies before each period, these cravings may actually have been triggered by what you have been eating throughout your entire cycle. Cravings may be a symptom of “oestrogen withdrawal,” aggravated by high fat (oestrogen-boosting) foods eaten over the entire month, and controlled by consistently eating nutritious, low-fat foods. That said, it is important to note that sugar affects different people in different ways. Initially, sugar increases a brain chemical called serotonin, which plays an important role in moods and sleep. The more sugar there is in a meal, the more serotonin your brain will produce. For some, this effect is a pleasurable one. For others, it causes irritability, fatigue, and depression, and very sensitive people can be adversely affected simply by drinking fruit juice regularly. A few days of sugary foods—even juices—can be all it takes to send them into depression. To test whether sugar is the culprit in premenstrual moodiness, try eliminating all sugars (including natural fruit sugars) from your diet. Researchers have speculated that some people crave sugar to naturally compensate for inadequate levels of serotonin in their brains. But be careful not to confuse the immediate bliss of a sugary snack with long-term well-being. Monitor your moods throughout the day to get a feel for how your body handles sugar. Unlike simple sugars, complex carbohydrates are made of a long string of sugars that are released gradually after they are eaten. Some, such as beans and green, leafy vegetables, also have plenty of protein and fibre to balance them nutritionally, and they release their natural sugars more gradually than others, such as potatoes and white bread.
About 60 percent of women who suffer from mood disturbances each month find relief from selective serotonin-reuptake inhibitors (SSRIs) such as Prozac, Zoloft, or Paxil. The dose used to treat PMS is smaller than that used for depression and is therefore less likely to cause side effects. Several other medications are available when SSRIs do not help.
Vitamin B6 (pyridoxine) has been shown to reduce pain in some studies by increasing the neurotransmitters that inhibit pain sensations. Vitamin B6 also has been shown to help combat depression, irritability, and other symptoms in research studies. Spinach and soybeans are high in B vitamins and can help ease symptoms naturally. B vitamins have other useful effects as well, including helping remove estrogens from the liver. A diet low in B vitamins may allow oestrogen levels to rise. Look at the following table to see whether you have been including these healthy vitamin B6 foods in your diet.
We saw how oestrogen dominates during the first half of the menstrual cycle and progesterone during the second half. Among other roles, progesterone counteracts the effects of oestrogen, preventing too much stimulation of the uterus. However, if your ovary doesn’t release an egg—a so-called an ovulatory cycle, which is not uncommon in some women—no progesterone is made.
One way to bring back hormonal balance is by using natural progesterone cream. Extracted from yams and soybeans and concentrated in a laboratory, its structure is an exact duplicate of human progesterone. Although synthetic variations do exist, they can cause side effects. A common and convenient brand of transdermal progesterone cream is Pro-Gest, available from Transitions for Health. It is not recommended for women using oral contraceptives because they are getting progesterone from the pills themselves. For relief of menstrual pain, a two-ounce jar of progesterone cream is gradually applied to the skin over ten days, using up the jar just before the period is expected to begin. For some, smaller doses are effective. The cream should be applied to thin areas of skin such as the neck, upper chest, abdomen, and insides of the arms and legs, covering as wide an area as possible and varying areas to which it is applied. Allow two to three months to see benefits. Stopping the progesterone on the twenty-sixth day will allow your period to occur normally. If PMS symptoms continue, you may need a higher dose. Use 30 to 40 milligrams per day (about half of a 2-ounce jar per month) from day fifteen through twenty-six, until symptoms diminish. The rationale for a higher dose is that emotional tension is accompanied by the release of the “stress hormone” cortisol, which competes with progesterone for receptors on the cells.
Regular aerobic workouts can do wonders for your mind and body. Activity can help shed excess pounds and weight-related problems, reduce fluid retention, and alleviate stress. Exercise also releases endorphins (natural feel-good chemicals) in your brain to lift your spirits and ease mood disturbances.
Essential Fatty Acids
As mentioned earlier, prostaglandins, made from traces of fat in our cells, are among the main causes of menstrual pain and cramps. Reducing dietary fat decreases oestrogen levels and prostaglandin production in the uterine lining. But it is not just the amount of fat that matters. It’s also the type. When you reduce your dietary fat in a healthy way by eating more beans, peas, lentils, and a variety of vegetables rather than eating “lean” meat, low-fat dairy products, or “reduced fat” snack foods, you’ll get a nice helping of omega-3 fatty acids. You also can add ground flaxseeds to your cereal or bake it into your pancakes, muffins, or bread. This type of fat increases your production of helpful prostaglandins, the kind that inhibit inflammation. This often leads to milder menstrual symptoms. You can find omega-3s in a convenient form in flaxseed oil, normally taken as one to three teaspoons per day. And a diet rich in vegetables and beans in place of meat and dairy products will supply traces of these nutrients as well.
Menstrual Cycle Disturbances
A high-fibre, low-fat diet keeps oestrogen levels under control and can help ease painful menstrual symptoms. It also can have an effect on the menstrual cycle itself. To have the best chance of conceiving, each intricate reproductive function, including ovulation, must occur properly each month. It’s a delicate system. As a new cycle begins, your ovaries make oestrogen in ever-increasing amounts to ready the uterus for pregnancy. Two weeks into the cycle, one ovary releases a tiny egg. As the egg descends through the fallopian tube toward the uterus, timing is critical. It has just a few precarious days to unite with a sperm cell and implant on the uterine wall, where, hopefully, it will grow into a healthy baby.
Cycles gone awry may manifest as the absence of menstruation, infrequent menstrual flow, or anovulation, when no egg is released (often occurring with no visible symptoms).
One study from the University of British Columbia comparing ovulatory function between two groups of women—one vegetarian, the other no vegetarian—found that the vegetarians had fewer ovulatory disturbances. The vegetarians’ advantage apparently came from the diet’s hormone-taming effect. avoiding animal products and keeping vegetable oils low help you avoid wild swings in the amount of oestrogen that courses through your bloodstream, which can easily occur on fattier diets. And vegetables, fruits, beans, and whole grains provide the extra protection of fibre, helping to eliminate excess estrogens.
The benefits of a hormone-balancing diet are seen in better fertility, reduced menstrual symptoms, and most important, in its measure of protection against breast, uterine, and ovarian cancer. The effects are more far-reaching than you might have guessed. As a recent study has shown, a mother’s oestrogen level during pregnancy can even affect her daughter’s risk for developing breast cancer later in life. Researchers from Harvard University and Sweden found a 30 percent increased risk for babies who weighed more than eight pounds at birth—an indicator of oestrogen levels in pregnancy.
A Surprising Danger in Dairy Products
The majority of people, excluding Caucasians, have trouble digesting dairy products because they do not retain the enzymes for digesting milk sugars after infancy. Even though most Caucasian women—about 85 percent—have the genetic adaptation that allows them to eat dairy products without experiencing intestinal discomfort, it doesn’t necessarily mean that they are protected from the long-term negative effects elsewhere inside the body. Dairy can turn the ovaries into a silent battleground. Ongoing research by Daniel Cramer, M.D., at Harvard Medical School has shown how dairy products can affect the ovaries: When you eat or drink dairy products, you ingest lactose, a double sugar that must be broken down into two smaller sugars—glucose and galactose—during digestion. It appears that galactose is toxic to the ovaries. The more milk products you consume, the more this potentially toxic substance passes into your bloodstream. Compounding the problem, some women have low levels of a certain enzyme needed to break apart this sugar. For them, galactose builds up dangerously. Its toxic effect on the ovary is reflected in infertility and higher cancer rates. Dr. Cramer and others have confirmed a correlation between the amount of lactose consumed and ovarian cancer rates. For instance, in the Nurses’ Health Study, which included 80,326 women, those who consumed the highest amount of lactose (one or more servings of dairy per day) had a 44 percent greater risk for all types of invasive ovarian cancer, compared with those who ate the least (three or fewer servings monthly). High-lactose foods include skim milk, ice cream, yogurt, and cottage cheese. Yogurt is a significant contributor of galactose to the diet because the bacteria used in its production break apart the lactose before you ever dig in your spoon. In each cup of yogurt you are essentially getting a serving of preformed galactose. So if you have been reaching for yogurt to keep calcium intake up, refer to the list of healthier high-calcium plant foods on page 35, or simply have a calcium-fortified glass of OJ each morning. Studies have shown that dairy consumed during pregnancy may have long-term health effects for a female baby as well. When a woman has lower levels of the enzyme needed to eliminate galactose, aided and abetted by high levels of lactose in her diet, toxic levels of galactose can harm the development of the baby’s growing reproductive organs, which may contribute to endometriosis later in life. More research is needed, but it is well worth being alert to the health effects of dairy products.
Endometriosis is a disease in which endometrial tissue, which normally lines the uterus, spreads and grows in other parts of the body. During the menstrual cycle, this misplaced tissue swells and bleeds, causing inflammation and pain. Over time this leads to scarring, which can lead to infertility. More than five million women in North America have been diagnosed with endometriosis, about 10 percent of women in their reproductive years. In a normal menstrual cycle, cells from the uterine lining are shed and passed out of the body at the end of the month. Endometriosis begins when some of these cells slip upward through the fallopian tubes that lead to the abdominal cavity. From there, they can end up attached to the intestinal tract, bladder, or elsewhere. A healthy immune system will normally find and eliminate out of place cells such as these. However, in endometriosis, they somehow survive and flourish, causing pain that can be severe, and a gradual loss of fertility. Avoiding certain foods may add a measure of protection against endometriosis. Although the reasons are not fully understood, caffeine consumption has been linked to the disease. Researchers at the Harvard School of Public Health found that women who have two or more cups of caffeinated coffee (or four cans of cola) per day were twice as likely to develop endometriosis. Foods that contain polychlorinated biphenyls (PCBs) also tend to encourage endometriosis. As we have seen, these chemicals are most concentrated in animal fat, particularly in fish. In your body, they impair your immune defences against abnormal cells, including those that have wandered out of the uterus into places where they don’t belong. Animals such as chickens, cows, and pigs are often fed grains that are treated with pesticides or contaminated with organochlorides. When we eat their meat or drink their milk, we invite these toxins into our bodies, where they can weaken our immune system. Eating organic produce, grown without chemical pesticides, is the best way to get your nutrients in as pure a state as possible. Washing and peeling vegetables and fruits also removes some harmful residues— something that simply can’t be done with animal products. What they ingest, to some extent, you ingest, often in a concentrated form. A prime target for these pollutants is a woman’s breast, where they dissolve into the fatty tissue and remain for a very long time. The ultimate victim is a nursing baby, who can receive up to half of all the dioxin a mother has accumulated in her body tissues. By avoiding fish, other meats, and cow’s milk, you can greatly reduce organochlorides in the foods you eat. It’s no surprise that researchers have found vegetarian women to have much lower levels of harmful pollutants in their breast milk.
Exercise is important as well. Women who work out for just two hours each week have only half the risk of endometriosis as other women. The protection apparently comes from a healthy reduction in hormone activity as well as a boost in immune system functioning. You will only know for sure whether you have endometriosis after having a medical procedure called a laparoscopy. It allows your doctor to look inside the abdominal cavity through a small incision made below the navel. Current treatments for endometriosis seek to minimize discomfort with anti-inflammatory painkillers. Danazol (a male hormone derivative) is essentially not used any more because of its masculinizing side effects. Gonadotropin releasing hormone analogues are most widely prescribed, as they effectively shrink endometriotic cells that have gone astray by reducing a woman’s oestrogen to menopausal levels. However, they are not without risks, and should only be used for up to six months. Surgical treatments include removing cell clumps or, in severe cases, severing pain nerves, or performing a hysterectomy, which, of course, results in infertility. Surgery and drug treatments have shown similar effectiveness, but usually are temporary measures, as they do not eliminate all of the troublesome cells. Some women find relief by changing their diet. In the same way that low-fat foods keep oestrogen levels in check to help ease menstrual pain, they can keep painful clusters of cells from growing and worsening. A diet change that reduces oestrogen can force these cells to wither and die. Another method for opposing oestrogen and reducing endometriosis pain is with natural progesterone, a cream made with wild yams or soybeans. John R. Lee, M.D., a leading expert on women’s health issues, recommends that progesterone be used in this instance from day six of the cycle to day twenty-six each month, using one ounce of the cream per week for three weeks, stopping just before the expected period. He cautions that patience will be in order, as it may take four to six months to see results. However, many of his patients, some with no relief from surgery, have had great success with progesterone treatments. Because endometriosis seems to be caused by an immune system failure to eliminate out-of-place cells, an immune-boosting diet may help prevent it. That means eating as little fat as possible and bringing in generous amounts of vegetables and fruits. Animal and vegetable fats actually suppress white blood cells’ power to annihilate dangerous cells. Cholesterol does the same sort of mischief. When researchers add cholesterol to white blood cells in a test tube, their immune strength is decreased.Natural immune-boosting foods are easy to find. Orange vegetables are rich in beta-carotene, grains and beans have plenty of vitamin E, and many fruits and vegetables are abundant in vitamin C and other antioxidants. By eliminating animal products and all of their fat and cholesterol, you’re giving yourself the best protection possible. When blood samples are studied to see whether certain white blood cells, called natural killer cells, are operating sufficiently, vegetarians do twice as well as omnivores. For them, powerful foods are on the job, protecting every cell.
There will never be a shortage of medications designed to mask the pain of menstrual symptoms and to counter other symptoms of hormonal changes. Sometimes they are just what you need for temporary relief. But painkillers don’t address the cause of the problem. As with so many health concerns, the easiest and best place to begin is with a healthy change to your diet. Better hormonal balance and smoother transitions will likely be found on your dinner plate.