Protein is one of the most important nutrients that helps your body to adapt and recover from exercises. The current recommendation is to consume 20 - 40 g of high-quality protein within a few hours after exercising (1, 2). In order for us to get results from exercising, it’s essential for us to maintain a balance between how much we train and how much recover.

In recent years, Veganism has become more and more popular, with an abundance of vegan sports products now being available in many of our supermarkets and health food shops (3-5). These products contain various proteins that come from beans, seeds, grains/starchy food (like potato and hemp) and proteins from pulses like pea and lentil. New brands even contain fungal, algae and bacterial protein.

Most plant proteins tend to be incomplete and lack different essential amino acids. In many cases only well-balanced mixtures of plant protein are considered to be complete and high-quality protein sources. However, concentrated soy protein is an exception because it is already a high-quality protein source (6, 7). High-quality means that all essential amino acids are present in the right amounts.

Research has shown that soy protein can stimulate muscle protein synthesis (a prerequisite for muscle growth and adaptation) like whey protein (8, 9). It has also been found that an increased amount of plant-based protein has been linked to positive effects on our health, e.g., markers of cardiovascular health (10-15).

Some people tend to avoid soy because rumour and misinformation about soy causing changes in sex hormones, such as testosterone, and induce breast growth in men. While soy does contain isoflavones, like phytoestrogens, studies have shown that these don’t lead to abnormalities or increases in reproductive hormones. These phytoestrogens are naturally occurring in plants and can also be found in chickpeas and other pulses. Although they have a similar chemical structure, they do not bind to oestrogen-receptors in the same way as the hormone oestrogen (16, 17). The level of isoflavone is reduced during processing and therefore the amount in soy protein isolate and concentrate, is low compared to raw soy protein products (18). When it comes to safety concerns related to isoflavones, there isn’t much to worry about and they aren’t a reason for us to exclude soy (protein) from a healthy and balanced diet.

Repair your body quicker, increase muscle growth and reach your goals by introducing soy protein into your daily lifestyle!

References

1. Jager R, Kerksick CM, Campbell BI, Cribb PJ, Wells SD, Skwiat TM, et al. International Society of Sports Nutrition Position Stand: protein and exercise. Journal of the International Society of Sports Nutrition. 2017;14:20.
2. Kerksick, Wilborn CD, Roberts MD, Smith-Ryan A, Kleiner SM, Jäger R, et al. ISSN exercise & sports nutrition review update: research & recommendations. Journal of the International Society of Sports Nutrition. 2018;15(1):38.
3. Mintel. #Veganuary: UK overtakes Germany as world’s leader for vegan food launches: Mintel Group Ltd.; 2019 [Available from: https://www.mintel.com/press-centre/food-and-drink/veganuary-uk-overtakes-germany-as-worlds-leader-for-vegan-food-launches.
4. The Good Food Institute. The Plant-Based Meat, Eggs, and Dairy State of the Industry Report 2020 [Available from: https://www.gfi.org/blog-state-of-the-industry-2020.
5. The Good Food Institute. The Cultivated Meat State of the Industry Report 2020 [Available from: https://www.gfi.org/blog-gfi-ssi-atlantic-salmon.
6. Hoffman JR, Falvo MJ. Protein - Which is Best? Journal of sports science & medicine. 2004;3(3):118-30.
7. Hughes GJ, Ryan DJ, Mukherjea R, Schasteen CS. Protein digestibility-corrected amino acid scores (PDCAAS) for soy protein isolates and concentrate: criteria for evaluation. Journal of agricultural and food chemistry. 2011;59(23):12707-12.
8. Churchward-Venne, Pinckaers PJM, Smeets JSJ, Peeters WM, Zorenc AH, Schierbeek H, et al. Myofibrillar and Mitochondrial Protein Synthesis Rates Do Not Differ in Young Men Following the Ingestion of Carbohydrate with Whey, Soy, or Leucine-Enriched Soy Protein after Concurrent Resistance- and Endurance-Type Exercise. J Nutr. 2019;149(2):210-20.
9. Tang, Moore DR, Kujbida GW, Tarnopolsky MA, Phillips SM. Ingestion of whey hydrolysate, casein, or soy protein isolate: effects on mixed muscle protein synthesis at rest and following resistance exercise in young men. J Appl Physiol (1985). 2009;107(3):987-92.
10. Pedersen AN, Kondrup J, Børsheim E. Health effects of protein intake in healthy adults: a systematic literature review. Food & nutrition research. 2013;57:10.3402/fnr.v57i0.21245.
11. Song M, Fung TT, Hu FB, Willett WC, Longo VD, Chan AT, et al. Association of Animal and Plant Protein Intake With All-Cause and Cause-Specific Mortality. JAMA Intern Med. 2016;176(10):1453-63.
12. Tielemans SM, Altorf-van der Kuil W, Engberink MF, Brink EJ, van Baak MA, Bakker SJ, et al. Intake of total protein, plant protein and animal protein in relation to blood pressure: a meta-analysis of observational and intervention studies. J Hum Hypertens. 2013;27(9):564-71.
13. Lonnie M, Laurie I, Myers M, Horgan G, Russell WR, Johnstone AM. Exploring Health-Promoting Attributes of Plant Proteins as a Functional Ingredient for the Food Sector: A Systematic Review of Human Interventional Studies. Nutrients. 2020;12(8).
14. Chalvon-Demersay T, Azzout-Marniche D, Arfsten J, Egli L, Gaudichon C, Karagounis LG, et al. A Systematic Review of the Effects of Plant Compared with Animal Protein Sources on Features of Metabolic Syndrome. The Journal of nutrition. 2017;147(3):281-92.
15. Shang X, Scott D, Hodge AM, English DR, Giles GG, Ebeling PR, et al. Dietary protein intake and risk of type 2 diabetes: results from the Melbourne Collaborative Cohort Study and a meta-analysis of prospective studies. The American journal of clinical nutrition. 2016;104(5):1352-65.
16. Haun CT, Mobley CB, Vann CG, Romero MA, Roberson PA, Mumford PW, et al. Soy protein supplementation is not androgenic or estrogenic in college-aged men when combined with resistance exercise training. Sci Rep. 2018;8(1):11151.
17. Hamilton-Reeves JM, Vazquez G, Duval SJ, Phipps WR, Kurzer MS, Messina MJ. Clinical studies show no effects of soy protein or isoflavones on reproductive hormones in men: results of a meta-analysis. Fertility and Sterility. 2010;94(3):997-1007.
18. Messina M. Soy and Health Update: Evaluation of the Clinical and Epidemiologic Literature. Nutrients. 2016;8(12).