Apr 6, 2019
Four Good Reasons to Embrace Soy (Not Just for Hippie Vegans).
Soy is a win for your taste buds, your body, your planet, and your wallet.
As much as I dislike the term ‘superfood’, soy just may be worthy.
Soy is a not only highly nutritious, delicious, and versatile, but also easy on the planet, and your wallet.
If you are one of the <1% who are allergic to soy, there’s not much I can offer besides my condolences. However, if you are afraid that soy will cause breast cancer, or give you man-boobs, I strongly encourage you to educate yourself on soy safety.
The latest science tells us that soy is not only safe, but may have health benefits. Fears of soy-based foods, and the phytoestrogens they contain, are based on weak studies that have been trumped by stronger evidence in favour of soy safety. Get the whole story in my sister article: Soy: To Fear or Not to Fear and check out this article’s appendix for links to “soy is safe” statements from a slew of leading medical organizations.
What is soy, anyways? Soy products come from the beans of Glycine max, a plant native to East Asia, belonging to the pea family. Soybeans are consumed in many forms, from immature beans (edamame) to tofu, to soy milk, to soy sauce, to purified protein powders. See how tofu and soy milk are made with this simple chart.
This article showcases soy’s many winning features. Soy-based foods are delicious, versatile, affordable, and exceptionally nutritious. Their environmental footprint is dramatically smaller than that of meat. Last but not least, they are wallet-friendly.
Yum Factor
Let’s whet our appetites with a few of the many ways you can enjoy soy.
Hungry? Tickle your umami taste receptors with grilled tofu and mushrooms, toss some edamame into a savoury soba noodle salad, enjoy a colourful tofu and veggie stir fry, or double-down with a Hoaxy-Poke bowl.
Thirsty? Sip a cool glass of soy milk, linger over a soy latte; or slurp a protein-powder-boosted smoothie after pumping iron.
Fun fact: You are likely eating more soy than you realize, especially if you eat animal products.
The vast majority of soy is used as animal feed. Of the 284 million tonnes of soy produced globally in 2013-14, 75% was used as animal feed. Soy content per kilogram is highest for broiler chicken, farmed fish, pork, and beef.[Source]
Nutrition
Soy is a rockstar on the nutritional front. It is one of the best, if not THE best, plant-based source of protein, both in terms of quantity and quality.
Soy rivals fattier meats such as ground beef when it comes to protein per calorie. At about 34% of calories from protein, edamame outshines Kirkland beef patties (26% of calories). Unsweetened soy milk is similar to 1% dairy milk, at about 8 grams of protein per cup and 30% (or more) of calories from protein.
Soy also shines when it comes to protein quality, and gets the esteemed honour of being labeled a “complete protein”. It gets a perfect, or near-perfect score according to common measures of protein quality, such as the Protein Digestibility Corrected Amino Acid Score (see PDCAAS), because it supplies ample amounts of all nine essential amino acids.
As an aside, this perfect amino acid profile is overkill. Even for vegans, it’s harder than you think FAIL to meet all your amino acid needs. Anyone that eats a varied diet spanning multiple food groups, and get enough total protein, should be golden [See Busting the Myth of Incomplete Plant-Based Proteins].
Soy is also rich in fiber, healthy (unsaturated) fats, and many micronutrients such as B vitamins, potassium, and magnesium. Soy is lower in carbohydrates than many other legumes, which can be a plus or a minus depending on your nutritional targets!
Soy critics like to point out that soy contains two types of compounds with the ominous ‘anti-nutrient’ label: phytates and lectins, known to reduce mineral absorption and impact gut integrity. The accusation is true, but I vehemently disagree with the conclusion that we should avoid these foods.
Shunning soy (and other legumes) because of their phytates and lectin content is like throwing out the baby with the bathwater.
I can say this with confidence because plant-rich diets including those with plenty of legumes and whole grains (= phytate and lectins) are consistently shown to be associated excellent long-term health (source). While these uncontrolled studies have many limitations, they clearly demonstrate that it’s easy to thrive on a plant-rich diet in spite of the ‘anti-nutrients’ they contain.
To make your beans even more nutritious, be mindful of how you prepare them. Most lectins can be inactivated in a big way using moisture, heat, and other strategies:
Tip for overcoming antinutrients:
Soaking, rinsing, sprouting, fermenting, boiling soy and other beans can dramatically reduce their lectin content.
Another simple strategy to beat anti-nutrients at their own game is to dial up your intake of the relevant minerals ( iron, zinc, calcium, magnesium). Some nutritional guidelines already reflect differing bioavailability based on food source (such as recommended iron intakes in US), and more elaborate modeling is underway, such as Europe’s zinc guidelines based on phytate levels [Source].
Environment
Soy shines brightly on the environmental front.
Fun Fact: If Americans swapped half of their burgers from ground beef to a soy-based burger ( e.g. the Impossible Whopper), the greenhouse gas impact would be equal to that of taking 13 million cars off the road! [see Appendix ].
Compared to ground beef, a soy burger uses / causes only:
- 8% water contamination
- 11% global warming potential
- 4% land use
- 13% water consumption
Eco tip:
Ironically, choosing soy products over animal products actually reduces habitat losses due to soy — because eating it directly requires so much less than fueling animals.
The other environmental benefit of soy is its positive impact on soil quality. Soybeans and other legumes infuse the soil with nitrogen, which would would otherwise need to be added through fertilizers. They do this through a process called “nitrogen fixation” [source]. Other benefits of soy crops include increasing soil organic matter, improving soil porosity, recycling nutrients, improving soil structure, decreasing soil pH, diversifying the microscopic life in the soil, and breaking disease build-up and weed problems of grass-type crops [source].
Cost
Soy is a low-cost source of high-quality nutrition.
The cheapest way to get your protein is from dried beans and legumes, which work out to about 1–2 cents per gram of protein [Source]. The price per gram of protein for tofu (extra firm) is slightly higher, and is similar to that of cheap ground beef — about 3 cents per gram of protein. Shelled edamame is pricier, at about 6 cents per gram of protein, while soy protein powders fall in the middle at about 3–5 cents per gram of protein.
All of these numbers skyrocket when you opt for organic. Whether or not (and when) this switch is worth the money is a topic for another time!
Conclusions
Whether you’re vegan, vegetarian, or omnivorous, I encourage you to explore new ways to enjoy soy and all that it offers. Plant-lovers can easily get all the protein then need and more, while meat-lovers can make a serious dent in their environmental footprint.
Eco Tip: The World Wildlife Foundation has concerns about habitat loss from soy crops, and are asking companies to source products based on soy that has been responsibly produced, such as soy that has been certified by the Round Table on Responsible Soy (RTRS) or ProTerra. They suggest contacting your favourite retailer, manufacturer or restaurant chain and asking them to source responsible soy. [Learn more]
Appendix
Expert positions on soy and health
- American Institute of Cancer Research
- MD Anderson
- Linus Pauling Institute
- Mayo Clinic
- Cleveland Clinic
- Physicians Committee for Responsible Medicine
… and more
Beef burger savings calculations
- 61 million tons CO2 equivalents saved = (4.5 million tons of beef per year*/ 2) x 27 kg CO2 equivalent savings per kilogram of beef**
- 61 million tons / 4.6*** = 13 million cars off the road (for a year)
Assumptions:
*US annual consumption of ground beef. 4.5 million tons kg (about 10 billion pounds)
**Savings per kg per beef. 27 CO2 equivalents based on Quantis report of 3.5 kg CO2 eq. per kg Impossible burger 2.0 and 30.5 kg CO2 eq. per beef burger.
**Auto emissions: A typical passenger vehicle emits about 4.6 metric tons of carbon dioxide per year. This assumes the average gasoline vehicle on the road today has a fuel economy of about 22.0 miles per gallon and drives around 11,500 miles per year. Every gallon of gasoline burned creates about 8,887 grams of CO2.
Cost per gram of protein
- A standard package of extra firm tofu (~340 grams) costs about $2 USD. At 60 grams protein per package, this works out to about 3 cents per gram of protein.
- A standard (non-organic) bag of shelled edamame (500g) costs about $3 USD. At about 50 grams of protein, this works out to about 6 cents per gram of protein.
- A bulk (500 gram) bag of soy protein powder contains about 400 grams of protein and costs about $15 US on Amazon .
