• The majority are without symptoms but may be associated with vague feelings of discomfort, pressure, congestion, bloating, and heaviness; can include pain with vaginal sexual activity, urinary frequency, backache, abdominal enlargement, and abnormal bleeding
• Abnormal bleeding in 30% of women with fibroids
Uterine fibroids are bundles of smooth muscle and connective tissue that can be as small as a pea or as large as a grapefruit. Although they are sometimes called tumors, fibroids are not cancerous. However, because they disrupt the blood vessels and glands in the uterus, they can cause bleeding and loss of other fluids. Around 30% of women over age 30 have at least one fibroid. Hysterectomies due to fibroids are the most common major surgery in women. Uterine fibroids are classified according to their location, as follows:
• Submucosal (just under the lining of the uterus)
• Intramural (within the uterine muscle wall)
• Subserosal (just inside the outer wall of the uterus)
• Interligamentous (in the cervix between the two layers of the broad ligament)
• Pedunculated (on a stalk, either submucosal or subserous)
Causes
Increases in local estrogen (specifically estradiol) concentration within the fibroid itself are thought to play a role in the development and growth of fibroids. Concentrations of estrogen receptors are higher in fibroid tissue than in the surrounding tissue. In addition to an excess of estrogen production within the body, a strong case can be made for the role of the most significant environmental factor assaulting female hormonal health—compounds known as xenoestrogens. These compounds are also known as endocrine or hormone disrupters, environmental estrogens, hormonally active agents, estrogenic substances, estrogenic xenobiotics, and bioactive chemicals. Examples of xenoestrogens include phthalates (used in plastics), pesticides, tobacco smoke by-products, and various solvents. Xenoestrogens enhance or block the effects of estrogen in the body by binding to estrogen receptors. They also promote a shift from healthy estrogen breakdown products to cancer-causing estrogen metabolites.
Therapeutic Considerations
Reducing the size as well as the symptoms of uterine fibroids with natural medicines is easily accomplished in most cases. Unfortunately, this statement is supported more by the clinical experiences of naturopathic physicians than by scientific evidence, though the approach is scientifically rational—that is, if uterine fibroids are caused by an excess of estrogen produced in the body as well as the effects of xenoestrogens, it makes sense that reducing estrogenic influences should shrink uterine fibroids. Keep in mind that as women pass through menopause there is less estrogen and so there will also be a tendency for the fibroid to shrink on its own.
The most important dietary recommendations are to eat a high-fiber diet rich in phytoestrogens (plant estrogens) and to avoid saturated fat, sugar, and caffeine. These simple changes can dramatically reduce circulating estrogen levels and reduce estrogen’s influence on the fibroid. One study looked at what happened when women switched from the standard American diet (40% of calories from fat; only 12 g fiber per day) to a healthier diet (25% of calories from fat; 40 g fiber). Results showed a 36% reduction in blood estrogen levels within 8 to 10 weeks.1
Phytoestrogens are able to bind to the same cell receptors as the estrogen your body produces. That’s a good thing, because when phytoestrogens occupy the receptors, estrogen can’t affect cells. By competing with estrogen, phytoestrogens cause a drop in estrogen effects, and are thus sometimes called antiestrogens. Great sources of phytoestrogens include soy and soy foods, ground flaxseed, and nuts and seeds. In particular, we recommend eating 1 to 2 tbsp of ground flaxseed per day.
These dietary recommendations have extreme significance not only in treating uterine fibroids but also in reducing endometrial cancer. Women with uterine fibroids have a fourfold increase in the risk of endometrial cancer. In a case-control study of a multiethnic population (Japanese, white, Native Hawaiian, Filipino, and Chinese) examining the role of dietary soy, fiber, and related foods and nutrients in the risk of endometrial cancer, 332 women with endometrial cancer were compared with women in the general multiethnic population, and all women were interviewed by means of a dietary questionnaire.2 The researchers found the following associations: a higher fat intake increased the risk of endometrial cancer, a higher fiber intake reduced the risk for endometrial cancer, and a high consumption of soy products and other legumes decreased the risk of endometrial cancer. Similar reductions in risk were found for greater consumption of other sources of phytoestrogens, such as whole grains, vegetables, fruits, and seaweed. The researchers concluded that plant-based diets low in calories from fat, high in fiber, and rich in legumes (especially soybeans), whole grain foods, vegetables, and fruits reduce the risk of endometrial cancer. These dietary associations may explain at least in part the lower rates of uterine cancer in Asian countries than in the United States. Vegetarians also have lower circulating estrogen levels than omnivorous women.3
Some have suggested that since soy foods are high in phytoestrogens (specifically isoflavones), which have a weak estrogenic effect, women with uterine fibroids or endometrial cancer should avoid phytoestrogens. This recommendation does not have merit. Soy isoflavones appear to be selective in terms of the tissues in which they have an estrogenic effect and the tissues in which their effect is antiestrogenic. Soy phytoestrogens do not appear to have an estrogenic effect on the human uterus and may in fact help shrink uterine fibroids due to an antiestrogenic effect. We recommend moderate but not excessive soy consumption in the range of 45 to 90 mg soy isoflavones per day. See the chapter “Menopause” for more information on the isoflavone content of soy foods.
Historically, naturopaths have used lipotropic factors such as inositol and choline to support the healthy detoxification of estrogen. Lipotropic factors promote the removal of fat from the liver. Lipotropic supplements usually are a combination of vitamins and herbs designed to support the liver’s function in removing fat, detoxifying the body’s wastes, detoxifying external harmful substances (pesticides, flame retardants, plastics, etc.), and metabolizing and excreting estrogens. These lipotropic products vary in their formulations depending on the manufacturer, but they are all similar and are meant for the same uses. Many now contain anticancer phytonutrients found in vegetables from the brassica family, such as indole-3-carbinol, di-indoylmethane, and sulforaphane. Research has shown that these compounds help to break down cancer-causing forms of estrogens to nontoxic forms, making them especially important for women with uterine fibroids.4–6
Many plants have been used in traditional herbal medicines in the treatment of women with uterine fibroids. Most of these plants contain phytoestrogens. However, their activity is certainly less than the effects of dietary phytoestrogens such as soy and flax. So we recommend focusing on dietary phytoestrogens rather than botanical sources.
QUICK REVIEW
• Increases in local estrogen (specifically estradiol) concentration within the uterine fibroid itself are thought to play a role in cause and growth.
• Xenoestrogens are thought to also play a role in uterine fibroids.
• The most important dietary recommendations are to eat a high-fiber diet rich in phytoestrogens while avoiding saturated fat, sugar, and caffeine.
• Research has shown that compounds from vegetables in the brassica family help to break down cancer-causing forms of estrogens to nontoxic forms, making them especially important in women with uterine fibroids.
TREATMENT SUMMARY
When uterine fibroids cause heavy bleeding, medical management is definitely necessary. Sometimes surgery is required. Newer, nonsurgical techniques such as high-intensity focused ultrasound are also now available.
Follow the guidelines in the chapter “A Health-Promoting Diet.” Consume a diet low in fat and high in fiber, whole grains, and soy foods and avoid saturated fats, sugar, caffeine, and alcohol. Soy isoflavone intake should be between 45 and 90 mg per day. Ground flaxseed at a dosage of 1 to 2 tbsp per day is also recommended.
• A high-potency multiple vitamin and mineral formula as described in the chapter “Supplementary Measures”
• Vitamin D3: 2,000 to 4,000 IU per day (ideally, measure blood levels and adjust dosage accordingly)
• Fish oils: 1,000 mg EPA + DHA per day
• Flaxseed oil: 1 tbsp per day
• One of the following:
Grape seed extract (>95% procyanidolic oligomers): 100 to 300 mg per day
Pine bark extract (>95% procyanidolic oligomers): 100 to 300 mg per day
Some other flavonoid-rich extract with a similar flavonoid content, super greens formula, or another plant-based antioxidant that can provide an oxygen radical absorption capacity (ORAC) of 3,000 to 6,000 units or more per day
• Specialty supplements, one of the following:
Lipotropic formula providing 1,000 mg betaine, 1,000 mg choline, and 1,000 mg cysteine or methionine
SAM-e: 200 to 400 mg per day
• One or a combination of the following:
Indole-3-carbinol (I3C): 300 to 600 mg per day
Di-indoylmethane (DIM): 100 to 200 mg per day