Soy and Ultra-Processed Foods: Are They Bad for You?

Conversations around ultra-processed foods, or UPFs, increased when Brazilian researchers created Nova, a food classification system that evaluates foods solely on the degree to which they have been processed, not on nutrient content. By nature of design, this classification system can unfortunately discredit nutritious processed foods, like plant-based and dairy alternatives. Learn more about ultraprocessed foods and how to address common questions from clients.

What are ultra-processed foods?
According to the Nova classification system, ultra-processed foods are defined as “industrial formulations of processed food substances (i.e., oils, fats, sugars, starch, protein isolates) that contain little or no whole food, and typically include flavorings, colorings, emulsifiers and other cosmetic additives.” Shelf-stable snacks, nutrition bars, meat alternatives, sweetened breakfast cereals, baked goods and more are all examples of ultra-processed foods. These foods are mostly made from ingredients extracted from foods and include ingredients like added vitamins or fats. Ultra-processed foods differ widely in their nutritional profiles. For example, there are many ultra-processed foods that are high in protein and contain heart-healthy fats.

It’s important to remember that, though not all processed foods are ultra-processed, almost every food undergoes some level of processing whether that be freezing, pasteurization, fermentation, canning or more, which can be confusing to clients and patients.

Can processed foods fit into a healthy diet?
Processed foods are accessible, convenient, and often cost-effective choices for many people. However, just like any food group or category, they can’t provide all the nutrients needed in a healthy diet. Helping to educate your patients or clients on overall healthy eating choices, like including nutrient-dense foods such as fruits and vegetables, legumes, grains and more – and how ultra-processed foods may fit into an overall healthy eating pattern – can empower them to make healthful choices that work for their lifestyle.

Soy’s role in ultra-processed foods
You might wonder where soy fits into all of this. Soy is available in a variety of forms, from minimally processed, such as edamame and whole soybeans, to more processed, like concentrated sources of protein often found in some ultra-processed foods thanks to their functionality and nutritional benefits. In addition, soy’s recognition as a heart - healthy ingredient makes it a favorable choice among food companies. Despite the food industry’s reliance on soy to produce nutritious and delicious products, some consumers may have questions about why soy is listed on the nutrition label and what its role is in ultra-processed foods.

Let’s look at some commonly asked questions, so you can be fully equipped to talk to your patients or clients about ultra-processed foods in a healthy diet, and the use of soy ingredients in UPFs.

Why is soy used in ultra-processed foods?
Soy is available in two main forms: soy protein, which is derived from soybeans, and soybean oil, which is commonly referred to as vegetable oil. Both products have a neutral flavor and taste, and offer beneficial nutrients, making them ideal ingredients in foods. They are added to a wide array of food products for their functional properties including hydrating, solubility, colloidal stability, gelation, emulsification and foaming.^1,2

What are some health benefits of consuming soy ingredients?
Soy protein is a complete protein source and the only plant protein that is comparable in quality to animal-based protein. Soy protein carries the U.S. Food and Drug Administration’s (FDA) heart health claim that states: “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.”³

Soybean oil contains mostly omega-6 polyunsaturated fats. This type of fat found in soybean oil may help to lower LDL cholesterol levels and reduce the risk of stroke and heart disease when eaten in place of saturated fats. Like soy protein, soybean oil also carries an FDA heart health claim, which states: “Supportive but not conclusive scientific evidence suggests that eating about 1½ tablespoons (20.5 grams) daily of soybean oil, which contains unsaturated fat, may reduce the risk of coronary heart disease.”⁴ 

How does soybean oil differ from other seed oils in ultra-processed foods?
While soy protein may be more closely associated with UPFs, soybean oil is also a common ingredient in processed foods thanks to its functionality. When considering oils, many patients are not aware of differences between a product made with soybean oil versus one made with other seed oils, such as corn or grapeseed oil. However, seed oils have varying dietary fat profiles which can offer different benefits when consumed.

Soybean oil has a favorable fatty acid profile. It contains mostly omega-6 (linoleic acid) polyunsaturated fat, which can help lower cholesterol and may reduce the risk of heart attack when eaten in place of saturated fat.5 With the exception of canola oil, soybean oil has more omega-3 ALA (another type of polyunsaturated fat) than other oils.⁵ Omega-3 ALA intake has been associated with heart health, plus emerging research on brain health shows encouraging findings related to cognitive impairment but more research is needed before meaningful conclusions can be made.6 Polyunsaturated fats, including omega3s, also help form the cellular membranes in all the cells in our body so your body needs it for survival.⁶

Are ultra-processed foods with soy ingredients healthier than those without?
In any food product, soy plays an important functional and nutritional role. In a nutrition bar, for example, soy protein can offer a complete protein source as well heart health benefits.

One common concern is that ultra-processed foods may lead to an excess in calorie intake which may contribute to obesity. However, research shows that this concern does not hold up when comparing soy-based products, like soy-based burgers and soy milk, to their animal-based counterparts.⁷ In fact, soy can deliver high-quality protein that is comparable to animal-based products, and in some instances, fiber, which is an under-consumed nutrient.

It’s true that many ultra-processed foods are not nutritious. But at the end of the day, it is important not to assume that “ultra-processed” equals poor nutritional quality. It’s all about a balanced diet and educating patients and clients to better understand the varying nutritional profiles of ultra-processed foods to figure out how they can fit into healthy eating patterns.

One easy tip is to encourage patients and clients to look at their food labels and, if a product contains soy, work with them to figure out the role soy plays in the product, and how they can fit the product into their daily diet.

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¹ Morr CV. Current status of soy protein functionality in food systems. J Am Oil Chemists Soc. 1990;67:265-71.

² Thrane M, Paulsen PV, Orcutt MW, Krieger TM. Soy protein: Impacts, production, and applications. In: Nadathur SR, Wanasundara JPD, Scanlin L, eds. Sustainable Protein Sources. United Kingdom: Academic Press; 2017:23-46.

³ Food Labeling: Health Claims; Soy Protein and Coronary Heart Disease. I Federal Register: (Volume 64, Number 206)];1999;57699-733

⁴ Erdman JW Jr. AHA Science Advisory: Soy protein and cardiovascular disease: A statement for healthcare professionals from the Nutrition Committee of the AHA. Circulation. 2000;102(20):2555- 2559. doi:10.1161/01.cir.102.20.2555

⁵ Messina M, Shearer G, Petersen K. Soybean oil lowers circulating cholesterol levels and coronary heart disease risk, and has no effect on markers of inflammation and oxidation. Nutrition. 2021;89:111343. doi:10.1016/j.nut.2021.111343

⁶ Sala-Vila A, Fleming J, Kris-Etherton P, Ros E. Impact of α-Linolenic Acid, the Vegetable ω-3 Fatty Acid, on Cardiovascular Disease and Cognition. Adv Nutr. 2022;13(5):1584-1602. doi:10.1093/advances/nmac016

⁷ Messina M, Sievenpiper JL, Williamson P, Kiel J, Erdman JW. Perspective: Soy-based meat and dairy alternatives, despite classification as ultra-processed foods, deliver high-quality nutrition on par with unprocessed or minimally processed animal-based counterparts. Adv Nutr. 2022;13(3):726-738. doi:10.1093/advances/nmac026