Plant-based foods are a good choice as part of a woman’s healthy diet.
- Bone health: Calcium loss increases during menopause because of the loss of oestrogen. Many nutrients help to keep bones healthy, so it’s important that the diet is balanced containing calcium and vitamin D.
- Hot flushes: The impact of soya and isoflavones on alleviating hot flushes during the menopause has been the focus of a considerable number of investigations.
Cholesterol-lowering: Plant-based foods and eating patterns tend to be lower in saturated fat. It’s widely accepted that a reduced saturated fat intake is associated with lower total blood cholesterol and LDL-cholesterol.
- Plant foods and plant-based eating patterns have shown a number of beneficial characteristics in cancer. Health professionals can reassure their patients with breast cancer that soya products are completely safe and may even have long term protective effects on health.
- Following an exhaustive review (November 2012) of the latest evidence, the American Institute for Cancer Research (AICR) has categorically stated that soya foods are perfectly safe to be consumed by women pre and post breast cancer diagnosis.
Adequate calcium intake and vitamin D status is required for optimal bone health. Also, ensuring a sufficient protein intake is important to keep bones healthy.
Evidence from observational studies indicates those who follow plant-based eating patterns have a healthy bone mass, with no difference in bone mass between omnivore and vegetarian populations.
However, it appears that those who consume vegan-type diets should take care to preserve protein and calcium intake, particularly during adolescence and young adulthood when peak bone mass is attained. There are a wide variety of plant-based protein sources, including peas, beans, lentils, nuts, soya dairy alternatives, tofu and soya mince, that can be consumed to ensure protein intakes are maintained. To make sure sufficient calcium is provided in the diet preference should be given to dairy alternatives fortified with calcium. Calcium is also found in plant foods such as dried fruits, nuts, green leafy vegetables (especially Kale and Pak-Choi, but not spinach), sesame seeds and tahini.
A more alkaline diet, rich in fruit and vegetables with smaller amounts of meat, reduces the acid/base challenge that can result in minerals such as calcium being leached out of bones.
Plant-based eating tends to be associated with other beneficial lifestyle factors, such as being more physically active, smoking less and an overall lower energy dense, nutrient-rich diet, all of which contribute to good bone health.
As soya foods provide high quality protein and many are also a good source of calcium, soyaa can help and support normal growth and bone development. Many other plantbased drinks are enriched with calcium and vitamine D. As a result these foods can be helpful in maintaining bone health.
Information from the Adventist Health Studies provides an insight into weight status as people progress from a vegan diet through to an omnivore diet. As more animal products are included in the diet, BMI gradually increases.
Plant-based eating, that includes eating more fruit, vegetables, legumes, whole-grains, nuts and seeds and limiting the amount of energy-rich foods, is a simple and effective way to manage weight.
Hormone Replacement Therapy (HRT), which involves taking estrogen with or without progestin, effectively alleviates these menopausal symptoms. However, since results from the Women’s Health Initiative (WHI) have been published, many women are unwilling to take HRT because they’re concerned about some of the potential side-effects. In this study it was found that women who received hormone therapy actually had a higher risk of heart disease, stroke, and some types of cancer (breast and endometrial cancer) than women who didn’t receive hormone therapy. As a result, many women are looking for alternative solutions.
The severity and frequency of menopausal symptoms are remarkably lower in Asian women than in Western women. In Asia, only 10% to 20% of postmenopausal women experience hot flushes compared to 50% - 70% of women in Western Countries. A possible reason for this could be due to the higher intake of soya, and their respective isoflavones, among Asians.
This has been confirmed in many clinical studies which have found that hot flush frequency and/or severity is reduced in groups receiving isoflavones compared to placebo groups.
The newest meta-analysis by Taku et al in 2012 found that soya (equivalent to 2 - 3 servings a day) reduces the number of hot flushes by 20% and reduces the intensity of hot flushes by 25%. This meta-analysis is based on data from 19 studies involving over 1500 subjects investigating the impact of soya isoflavones on menopausal symptoms.
Reducing uncomfortable symptoms can greatly improve the quality of life for menopausal women. As such women should consider including soya foods into their diet as part of a lifestyle approach to help manage these symptons.
The World Cancer Research Fund confirms that soya foods fit in to healthy eating guidelines for breast cancer survivors.The World Cancer Research Fund published its update report “Diet, Nutrition, Physical Activity and Breast Cancer Survivors” in October 2014. The independent panel of scientists concluded that there are indications of links between better survival after breast cancer and:
- A healthy body weight
- Being physically active
- Eating foods containing fibre
- Eating foods containing soya
- A lower intake of total fat and, in particular, saturated fat
Body weightBefore and after diagnosis of breast cancer. The scientific evdience demonstrates that there is a link between a healthy BMI and surviving breast cancer. However, the report highlights that more research is needed to fully understand why overweight and obese women have a greater risk of dying from the disease.
Risk of developing breast and other cancer. The report also highlights that being overweight or obese is associated with the development of eight cancers: bowel, womb, oesophageal, kidney, pancreatic, ovarian, gallbladder as well as post-menopausal breast cancer.
Physical activityBoth before and after diagnosis, being physically active provides women with a greater chance of surviving breast cancer.
Although the evidence is not conclusive and more research is needed especially with respect to diet and cancer survival, the report does highlight that despite the limited evidence, there are general and consistent findings from various studies:
Eating more fibre containing foods. Both before and after diagnosis – eating more fibre may reduce the risk of dying from breast cancer.
Soya food consumption and breast cancer survivors. Women who consume more soya foods after diagnosis, may improve their survival rate whilst a higher consumption of soya foods afterprimary breast cancer diagnosis may reduce risk of all cause mortality.
High fat and saturated fat intakes. Consuming high fat and saturated fat diets prior to diagnosis, may place women at increased risk of dying following their diagnosis
The American Cancer Reserarch Institute has developed some impactful on-line visuals to communicate the findings: http://www.aicr.org/learn-more-about-cancer/infographics/breast-cancer-survivorship.html
Breast cancer is by far the most frequent cancer among women with an estimated 425,000 new cancer cases diagnosed in 2008 (28.2% of all cancers) in Europe and almost 129,000 deaths per year. Breast cancer is still the leading cause of death from cancer in women. In Asian countries, the incidence of breast cancer is 2.4 times lower than the incidence in Western counties: the age-standardized incidence rate in Europe is 62.8 per 100,000 compared to 26.1 per 100,000 in Asia.
Migrant studies indicate that it takes 2-3 generations for women moving from a low risk to a high risk country to adopt the risk of the host country. After 100 years in Hawaii, Japanese-Americans now have a breast cancer risk close to that of Caucasian women. This suggests that some etiological factors may act during childhood or adolescence (11).
Soya intake early in life
Several epidemiologic studies have examined the effect of early soya intake on adult breast cancer risk later in life. During adolescence, the developing breast tissue is most sensitive to environmental stimuli. The observation that soya intake during childhood and adolescence is associated with a reduced risk of breast cancer later on in life is consistent with migration data, highlighting that early life events are particularly important for breast cancer.
The Shanghai Breast Cancer Study found that adolescent soya food intake was associated with a decreased risk of breast cancer: young women consuming around 2-3 soya foods a day were half as likely to develop breast cancer later in life compared to young women who rarely consumed soya. Another study in the US came to similar conclusions: women who reported consuming soya four times a week during adolescence had a 35% lower risk of developing breast cancer later in life compared to those having soya less than once a month.
Overall there is strong scientific evidence to recommend young girls consume at least 1 serving of soya foods a day. Protection may stem from the estrogenic activity of isoflavones, resulting in breast cell differentiation enabling the breast tissue to be more resistant to carcinogens later in life.
Scientists from AICR extensively evaluated the findings from laboratory, animal and human studies and have concluded that regular soya isoflavone consumption has no detrimental effect, and in fact has the potential to reduce breast cancer risk. This is also the case for breast cancer survivors consuming soya foods.
Breast cancer patients: soya foods are breast cancer friendly
The Shanghai Breast Cancer Survival Study followed 5042 female breast cancer survivors in China. Soya food intake was associated with lower mortality (29%) and recurrence (32%) among breast cancer patients. The association of soya food with mortality and recurrence appears to be dose related until soya food intake reached around 12 g of soya protein a day; no additional benefits on mortality and recurrence were observed with higher intakes of soya food. This study suggests that moderate soya food intake (12 g of soya protein per day) is safe and potentially beneficial for women with breast cancer. Furthermore, soya food intake did not interfere with tamoxifen use.
Similarly two large studies in breast cancer patients in the US have found similar reassuring results.
In early 2013, Pamela Magee reviewed all the data, involving over 9000 breast cancer survivors, and again concluded that soya consumption did not have any adverse effects. In fact, regular soya consumption had the potential to lower mortality and tumor recurrence rates – depending on the type of breast tumor involved. Women consuming around 12g of soya protein daily (equivalent to 400ml soyadrink or 80g of soya mince) had a 25% lower risk of breast cancer recurrence compared to women who consumed no soya. This favourable effect in cancer survivors was seen in patients treated with and without tamoxifen.
Extensive analysis of the current research shows that consuming 1-2 servings of soya foods (equivalent to 1-2 glasses of soya drink or 50-100g of soya mince/tofu) a day has the potential to lower breast cancer risk, and for some breast cancer survivors can lower mortality and tumor recurrence rates.
In 2014 a meta-analysis consisting of nine trials comprising 197 pre-dialysis chronic kidney disease patients reviewed the effect of soy protein consumption.
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