The Perfect Plant Protein: Soy

Author: Dr. David Heber, M.D., PhD, FACP, FASN, Chairman, Herbalife Nutrition Institute

As doctors we know the critical importance of maintaining a healthy diet and exercising regularly and are obliged to propagate the same for our patients. For me, as a medical doctor, who early in my career chose to focus on understanding nutrition’s impact on our bodies, I am a proponent of a balanced diet that includes healthy plant-based foods – especially soy protein.

Obesity is linked to many potentially lethal health conditions including, heart disease, high blood pressure and diabetes.  In Asia and the Pacific, at least two out of five adults are overweight and obese and this is of significant concern for individuals, communities, healthcare providers and public health experts alike.  As the founding director of UCLA’s Center for Human Nutrition, I have spent decades researching the impact of plant-based proteins – such as soy – on patients vs. a meat-based protein diet. Substituting soy protein and other plant proteins for high-fat animal meats can result in better weight control and lower cholesterol and blood pressure levels, although changing one’s diet is not a substitute for seeking medical advice or treatment for these conditions. Reducing extra calories, saturated fat, and cholesterol from meats and substituting soy protein in shakes and foods can help our patients maintain a healthy weight, which will also support them in healthy immune function. 

Choosing the source of protein that’s best  

With consumers seeking more plant-based proteins and many choices, including rice, beans, quinoa, pea, soy, and others, it can be tough for consumers to know which plant-based proteins are best for them. The truth is, not all plant-based proteins are created equal. Unlike the other plant-based proteins, soy is the only one considered a complete protein. Soy contains all 21 amino acids, including the nine essential amino acids that the body cannot make. The essential amino acids can come from the foods we eat. Soybeans are also a good source of fiber, minerals, and complex carbs. Soy protein contains phytonutrients called soy isoflavones, which act as antioxidants, and they feed healthy gut bacteria, making them “prebiotics.” Soy may also benefit the heart.  Some studies have shown that 25 grams of soy protein a day, as part of a diet low in saturated fat and cholesterol, may reduce the risk of heart disease, although the total scientific evidence is not conclusive.  

Once believed myths about Soy, no longer holds true  

Though Soy isoflavones are beneficial to the human body as stated above, there are numerous myths surrounding them. The root concern is that Isoflavones have chemical structure like estrogen, a hormone produced by our body, which when exceeded can be detrimental to the balance of our system. The critical difference to note here is that the effects from these phytoestrogens are different on the human body than that of the hormone estrogen and consuming soy does not expose the body to flooding of estrogen into our system. 

Several years ago, there were reports that soy had a link to breast cancer. However, scientific research has  debunked this premise, and there is no evidence linking soy consumption to breast cancer. Based on several studies, the  American Cancer Society concludes there is no harm from eating soy protein or soy foods, and there is mounting evidence that nutrients in soy foods may lower the risk of  breast cancer. 

Soy has its share of bad rap when it comes to men’s health but extensive clinical data shows that neither soy foods nor isoflavones affect testosterone and estrogen levels in men. Research has also negated the myth that soy consumption could cause enlarged breasts in men. In fact, research indicates soy may reduce the risk of prostate cancer in men. 

On the contrary to these common myths, soy protein supports muscle building and recovery especially when training with resistance and weights. Soy is also a better option for the environmentally conscious individuals, as going green prevents disruption of the food chain and keeps our body healthy and happy. 

Now that we have unravelled the joy of soy, there are many ways patients can include this nutritious and tasty beans into their diet. They can be directly consumed from food rich in soy such as edamame (whole soybeans), tofu, tempeh, or a convenient, on the go option, a soy protein meal replacement shake. Soy is truly the perfect choice of protein in comparison to animal sources and other plant options as it’s not only of high-quality and a complete source of protein but also offers health benefits such as lowering LDL (low-density lipoprotein) and keeping HDL (high-density lipoprotein) stable. Its’s also the best option for vegans and those who cannot consume dairy. As the medical community continues to study how people can best protect themselves against any viral infections now or in the future, in addition to frequent handwashing, face masks, and social distancing, a balanced diet, and lifestyle that includes healthy proteins like soy and regular exercise should also be shared as part of our daily consultations to patients to enable them to  keep fit and strong.