Soyfoods are uniquely positioned to meet the needs of the world’s aging population—those who are age 60 and older. Globally, the number of older people is growing faster than the population in all other age groups. In 2017, more than 962 million people around the world were aged 60 or older. That number is expected to double by 2050 to reach more than 2 billion.[1]
Currently, plant-based eating is one of the hottest dietary trends. Among the plant proteins, soyfoods in particular have much to offer in meeting the health, nutrition and economic considerations of the world’s aging population.
The U.S. Soybean Export Council shares information about current trends that create a demand for U.S.-grown soybeans. This is Part Two of a two-part report on the benefits of soyfoods for an aging global population.
Soyfoods Help Lower the Risk of Certain Types of Cancer
Older adults should keep in mind that consuming soyfoods may help reduce the risk of developing prostate cancer[2]—the most common cancer among American men, as well as breast cancer,[3][4]the most common cancer among American women, with the exception of skin cancer. Intriguing research suggests one factor that may be contributing to the low prostate cancer rates in Asian counties is the consumption of soyfoods. In Japan, as well as in some urban areas of China, the average soy consumption is around 1½ to 2 servings per day.[5] Research suggests that consuming approximately two servings of soyfoods per day may be associated with a one-third reduction in the risk of postmenopausal breast cancer.[6]
For survivors of breast cancer, there is good news as well. Both the American Institute for Cancer Research[7] and the American Cancer Society[8] have concluded that soyfoods can safely be consumed by breast cancer patients. In fact, research involving more than 11,000 women with breast cancer shows that high soy intake after a diagnosis of breast cancer reduces risk of recurrence by 26% and risk of dying from breast cancer by 16%. [9] One serving of soy is the equivalent of 1 cup of soymilk, ½ cup tofu, ½ cup shelled edamame or ¼ cup of soynuts.
Soyfoods May Contribute to Brain Health
People aged 65 to 75 may be interested in new research from the University of Illinois, suggesting that for those in that age group, consuming a variety of nutrients may be associated with better brain function. Omega-3 fatty acids, for example, were associated with general intelligence, while omega-6 fatty acids were associated with skills involving mental control and self-regulation.[10] Some of the best sources of both omega-3 and omega-6 fatty acids are soybean oil, as well as many soyfoods. Furthermore, a 12-week study found significant improvements in cognitive function among women whose diet was supplemented with soy protein in comparison to whey protein supplementation.[11]
Soy News for Diabetics
Eating soyfoods has been shown that they may improve glucose tolerance in people with diabetes, and to decrease blood glucose.[12] Also, a large Japanese study found that among women, frequent soyfood consumers were 50% less likely to develop diabetes over a 10-year period.[13] Unlike other beans, soybeans are very low in carbohydrates,[14]as are the traditional soyfoods such as tofu, so they can help with glycemic control.[15]
How Soyfoods Can Reduce Menopause Symptoms
Clinical studies have shown that consuming about 50 milligrams of soybean isoflavones, the amount in about two servings of soyfoods (such as 1 cup of soymilk and ½ cup of tofu) can reduce the number of hot flashes by about 50%.[16]
Looking at Potential Benefits of Soyfoods on Skin Health
It’s no secret that our skin changes as we age. Studies suggest that the plant estrogens (isoflavones) in soy may reduce wrinkles in young women and older women alike. For example, a new clinical study from Japan examined the potential benefit of soy for skin health in postmenopausal women who consumed about one cup of soymilk per day for eight weeks. The study found general improvement in skin health based on both subjective (questionnaires) and objective (skin biopsies) measurements of skin health.[17] These new results are consistent with previously published research.[18]
[1] United Nations, Department of Economic and Social Affairs, Population Division (2017). World Population Ageing 2017 – Highlights (ST/ESA/SER.A/397)]
[2]Applegate CC, Rowles JL, Ranard KM, et al. Soy consumption and the risk of prostate cancer: An updated systematic review and meta-analysis. Nutrients. 2018;10(1).
[3]Xie Q, Chen ML, Qin Y, et al. Isoflavone consumption and risk of breast cancer: a dose-response meta-analysis of observational studies. Asia Pacific journal of clinical nutrition. 2013;22(1):118-27.
[4]Zhao TT, Jin F, Li JG, et al. Dietary isoflavones or isoflavone-rich food intake and breast cancer risk: A meta-analysis of prospective cohort studies. Clin Nutr. 2019;38(1):136-45.
[5]Messina M, Redmond G. Effects of soy protein and soybean isoflavones on thyroid function in healthy adults and hy pothyroid patients: a review of the relevant literature. Thyroid. 2006;16(3):249-58.
[6]Xie Q, Chen ML, Qin Y, et al. Isoflavone consumption and risk of breast cancer: a dose-response meta-analysis of observational studies. Asia Pacific journal of clinical nutrition. 2013;22(1):118-27.
[7]American Institute for Cancer Research. Soy is safe for breast cancer survivors. http://wwwaicrorg/cancer-research-update/november_21_2012/cru-soy-safehtml(accessed Feburary 5, 2013). 2012.
[8]Rock CL, Doyle C, Demark-Wahnefried W, et al. Nutrition and physical activity guidelines for cancer survivors. CA Cancer J Clin. 2012;62(4):242-74.
[9]Chi F, Wu R, Zeng YC, et al. Post-diagnosis soy food intake and breast cancer survival: A meta-analysis of cohort studies. Asian Pacific journal of cancer prevention : APJCP. 2013;14(4):2407-12.
[10]Zwilling CE, Talukdar T, Zamroziewicz MK, et al. Nutrient biomarker patterns, cognitive function, and fMRI measures of network efficiency in the aging brain.NeuroImage. 2019;188239-51.
[11]Zajac IT, Herreen D, Bastiaans K, et al. The effect of whey and soy protein isolates on cognitive function in older Australians with low vitamin B12: A randomised controlled crossover trial. Nutrients. 2018;11(1).
[12]Glisic M, Kastrati N, Gonzalez-Jaramillo V, et al. Associations between phytoestrogens, glucose homeostasis, and risk of diabetes in women: A systematic review and meta-analysis. Adv Nutr. 2018;9(6):726-40.
[13]Konishi K, Wada K, Yamakawa M, et al. Dietary soy intake is inversely associated with risk of type 2 diabetes in Japanese women but not in men. J Nutr. 2019.
[14]Messina MJ. Legumes and soybeans: overview of their nutritional profiles and health effects. Am J Clin Nutr. 1999;70(3 Suppl):439S-50S.
[15]Feinman RD, Pogozelski WK, Astrup A, et al. Dietary carbohydrate restriction as the first approach in diabetes management: critical review and evidence base. Nutrition. 2015;31(1):1-13.
[16]Taku K, Melby MK, Kronenberg F, et al. Extracted or synthesized soybean isoflavones reduce menopausal hot flash frequency and severity: systematic review and meta-analysis of randomized controlled trials. Menopause. 2012;19(7):776-90.
[17]Nagino T, Kaga C, Kano M, et al. Effects of fermented soymilk with Lactobacillus casei Shirota on skin condition and the gut microbiota: a randomised clinical pilot trial. Beneficial microbes. 2018;9(2):209-18.
[18]Jenkins G, Wainwright LJ, Holland R, et al. Wrinkle reduction in post-menopausal women consuming a novel oral supplement: a double-blind placebo-controlled randomized study. Int J Cosmet Sci. 2014;36(1):22-31.
