Soy causes gout. Myth debunked!
Soy provides us with a significant source of protein, fiber, polyunsaturated fatty acids, as well as vitamins and minerals. There are a plethora of soy products available — from miso soup to tempeh, tofu to tau huay. Despite providing the greatest amount of plant-based protein, soy has earned a bad rep amongst some, who state it may cause undesirable side effects such as gout.
What is Gout?
Gout is a type of arthritis that occurs when uric acid crystals accumulate in the cartilage of joints. Uric acid crystals are waste products formed when purines are broken down. Purines are compounds which occur naturally in the body and in foods like red meat (eg. beef and pork) and soy. Uric acid is removed via urine. But, an overproduction can result in small, jagged crystals being formed in joint fluid, which brings about pain and inflammation — gout.
Although purine-rich foods like red meat cause increased levels of uric acid in one's blood, soy doesn’t seem to have this effect. A study done on over 50,000 individuals in Singapore, found that participants who consumed the greatest amount of soy products were actually at lower risk of gout, compared to those who ate the least. Another study also highlighted that consumption of animal-based protein sources was linked to excess blood uric acid, while consumption of soy products was linked to lower likelihood of excess blood uric acid. Lastly, another study done on over 47,000 men allowed researchers to establish that moderate intake of purine-rich vegetables, including beans, was not associated with an increased risk of gout.
The findings of the studies above can be attributed to a study done in Japan. It was found that soy may increase uric acid excretion, and thereby, decrease amount of uric acid crystals which will be formed, hence, playing no role in increasing chances of gout.
Not just the diet...
Furthermore, gout is a disease that has mainly unmodifiable factors. For instance, age and gender. Older individuals are more at risk and males are 3-4 times more likely than females to develop gout. Genetics also plays a part. Some people are more susceptible to having higher uric acid levels, and lower ability to eliminate uric acid.
Unfortunately for those with gout, adherence to a strict low-purine diet will only decrease uric acid by a minute amount. But restricting intake of foods that increase uric acid levels like red meat, beer, liquor, and high fructose corn syrup does help keep gout flares (“attacks” where intense pain and inflammation occurs) under control.
Keeping gout at bay
Therefore, what’s the best way to keep gout at bay? Achieving and maintaining a healthy weight! Like how being overweight can cause high blood pressure and high cholesterol, leading to heart disease, it can also cause high blood uric acid levels, and eventually, gout.
So, now that you know soy doesn’t give gout and how to keep gout at bay, let’s find out more about how soy may be good for us (especially our heart health)!
A Japanese study found that women who took soy products at least five times a week had a 45% lower risk of heart attacks and 69% lower risk of dying from heart disease, compared with women who ate soy products at most twice a week. Another study supported this, showing that soy food consumption was associated with lower risk of coronary heart disease. A Singapore study also stated that soy intake was not significantly associated with risk of cardiovascular mortality. All three studies were not supported by the soy industry in any way.
Of course, conflicting studies do exist, so keep in mind that neither soy, nor any other food items are a “superfood”. Instead of shunning soy entirely or consuming soy excessively, consider incorporating some soy products into your diet every now and then. This is a great way to add some variety and extra plant-based protein in your diet.
Arthritis Foundation, 2017. What Role Does Diet Play in Gout Management? [online]. Available at: http://www.arthritis.org/about-arthritis/types/gout/articles/purine-foods-gout-attack.php [Accessed 8 Nov. 2017].
Cheong, K., 2015. Gout patients can eat soy products, local study finds [online]. The Straits Times. Available at: http://www.straitstimes.com/singapore/health/gout-patients-can-eat-soy-products-local-study-finds [Accessed 8 Nov. 2017].
Harris, K., 2017. The truth about soy and tofu [online]. Mother Nature Network. Available at: https://www.mnn.com/food/healthy-eating/blogs/the-truth-about-soy-and-tofu [Accessed 8 Nov. 2017].
Kokubo, Y., Iso, H., Ishihara, J., Okada, K., Inoue, M. and Tsugane, S., 2007. Association of Dietary Intake of Soy, Beans, and Isoflavones With Risk of Cerebral and Myocardial Infarctions in Japanese Populations: The Japan Public Health Center Based (JPHC) Study Cohort I. Circulation [online], 116(22), pp.2553-2562. Available at: http://circ.ahajournals.org/content/116/22/2553 [Accessed 9 Nov. 2017].
Livestrong, 2017. Is Soy Bad for Gout Sufferers? [online]. Available at: https://www.livestrong.
com/article/385300-is-soy-bad-for-gout-sufferers/ [Accessed 8 Nov. 2017].
Ng, K., 2017. Low-carb diet may increase heart disease risk [online]. The Straits Times. Available at: http://www.straitstimes.com/singapore/health/are-diets-for-weight-loss-good-for-the-heart [Accessed 8 Nov. 2017].
Singh, J., Reddy, S. and Kundukulam, J., 2011. Risk factors for gout and prevention: A systematic review of the literature. Current Opinion in Rheumatology [online], p.1. Available at: https://www.ncbi.nlm.nih.gov/pmc/articles/
PMC4104583/ [Accessed 9 Nov. 2017].
Talaei, M., Koh, W., van Dam, R., Yuan, J. and Pan, A., 2014. Dietary Soy Intake Is Not Associated with Risk of Cardiovascular Disease Mortality in Singapore Chinese Adults. Journal of Nutrition [online], 144(6), pp.921-928. Available at: https://www.researchgate.net/publication/261373328_Dietary_Soy_Intake_Is_Not_Associated_with_
Risk_of_Cardiovascular_Disease_Mortality_in_Singapore_Chinese_Adults [Accessed 9 Nov. 2017].
Teng, G., Pan, A., Yuan, J. and Koh, W., 2015. Food Sources of Protein and Risk of Incident Gout in the Singapore Chinese Health Study. Arthritis & Rheumatology [online], 67(7), pp.1933-1942. Available at: http://onlinelibrary.wiley.com/doi/10.1002/art.39115/full [Accessed 8 Nov. 2017].
Villegas, R., Xiang, Y., Elasy, T., Xu, W., Cai, H., Cai, Q., Linton, M., Fazio, S., Zheng, W. and Shu, X., 2012. Purine-rich foods, protein intake, and the prevalence of hyperuricemia: The Shanghai Men’s Health Study. Nutrition, Metabolism and Cardiovascular Diseases [online], 22(5), pp.409-416. Available at: https://www.ncbi.nlm.nih.gov/pmc/
articles/PMC3150417/ [Accessed 8 Nov. 2017].
Zhang, X., Shu, X., Gao, Y., Yang, G., Li, Q., Li, H., Jin, F. and Zheng, W., 2003. Soy food consumption is associated with lower risk of coronary heart disease in Chinese women. Journal of Nutrition [online], 133(9), pp.2874-2878. Available at: https://www.ncbi.nlm.nih.gov/pubmed/12949380 [Accessed 9 Nov. 2017].