Understanding Processed Foods

04/01/2015

Processed foods often get vilified in today’s food environment, but that shouldn’t necessarily be the case. Processing foods can have benefits to improve food’s shelf life, reduce food waste, conserve resources and provide healthier and safer food.

To learn more about the facts and benefits of processed foods, we talked with Connie Weaver, PhD, Nutrition Scientist and Head of the Department and Distinguished Professor of Nutrition Science at Purdue University, who says processed foods may not be what you think.

Let’s talk about processed foods. You’re working with the American Society of Nutrition to define processed foods. Why is that important?

Dr. Weaver:

Defining processed foods has been challenging. When I talk to people about processed foods, I learn that they are not really meaning the level of processing. To a scientist, processing is how many steps the manufacturer of the food requires to transform it from the raw materials into the food you eat. So, to a scientist, highly processed foods mean things like bread, cheese, wine and yogurt. People say, that’s not what I mean – I mean junk food or empty calories. For consumers, it’s really not about the degree of processing, it’s about nutrient density or the formula of the food. We have to work on the definitions so everyone can talk together and have a more meaningful conversation about processed foods.

Are all processed foods bad?

Dr. Weaver:

Processed foods can be really healthy or less healthy depending on the formula or recipe. Processing steps can be used to improve the nutrient content. Manufacturers are reducing sugar, sodium and fat to improve the healthy foods, and adding or devising formulas for foods that have nutrients that people need.

The dietary guidelines have identified four shortfall nutrients: dietary fiber, vitamin D, calcium and potassium. This means most people are deficient in these nutrients and only with certain processed foods can you achieve those intake levels.

Soy beverages are an example of a processed food. Our laboratory studied calcium absorption from a soy beverage enriched with calcium and found it just as bioavailable, or absorbable, as cow’s milk. That caused USDA to change its rules and allow calcium-fortified soy beverage in school lunch and breakfast programs as an alternative to milk.

We need processed foods, because how else are we going to feed the world? We’re facing a future with nine billion people; you can’t have fresh food ready for harvest to meet all those peoples’ needs. In addition, processing can reduce waste. The efficiency for packaging and preserving food depends on maximizing resources, and the consumer relates to that. They want to save on waste and conserve resources.

Why do you think processed foods have a bad reputation?

Dr. Weaver:

Processed food can get a bad rap because people focus on the particular processed foods that are high in things we try to discourage and low on the nutrients we try to encourage. So, the “treat” foods. But shamefully, more than half of American adolescents get their calories largely from sugar-sweetened beverages and grain-sweetened desserts, like cookies, cakes and candies.

What else do you want people to know about processed foods?

Dr. Weaver:

Processed foods allow us to have food year ’round, so it’s good for availability. Another benefit of processed foods is food safety as further processing works to preserve the food and extend shelf life. This helps to reduce waste and conserve resources.

Some of the most important nutritional deficiencies in the world have been resolved because foods have been enriched and fortified with nutrients through processing. For example, adding iodine to salt cured goiter (an enlarged growth in your throat caused by iodine deficiency). Similarly, adding vitamin D to milk in our country has cured rickets (bow legs as a child due to vitamin D deficiency). More recently, we have medical foods for the immune-compromised. People with cancer or AIDS or diseases that can’t tolerate the risk of bacteria or an infection rely exclusively on processed foods.

Tell us about your research on processed foods.

Dr. Weaver:

About 20 percent of the vitamin D, calcium and potassium in our diet comes from processed foods. Research we conducted for the American Society for Nutrition Scientific Statement looked at what Americans eat and determined the impact of processed foods. We learned that processed foods provide more than their energy contribution in terms of the shortfall nutrients like fiber, vitamin D, potassium, and calcium, plus some additional B vitamins and other nutrients our bodies need. Processed foods provide way more nutrients of value than their calorie contributions.

Are there other processed foods with enhanced dietary attributes?

Dr. Weaver:

We have fresh fruits and vegetables all year long because of the modified atmosphere packaging. Salad in a bag is another example.

Bread can now have high fiber content but look and act like the soft, refined-grain bread that some people prefer. We can reduce salt and sugar and reduce the risks for obesity and diabetes.

Some modern technologies include baked French fries and fried chicken, without added oils. Deep-fat fryers in schools have disappeared because of improvements in the ability to have desired textures of fries without the added oils.

New processes allow us to remove fractions, making milk more easily digestible for those who can’t digest lactose. We can increase the fractions with protein and calcium in it.

What would you tell people who claim processed food is unhealthy or unnatural?

Dr. Weaver:

When people want to exclude whole types of food, whether it’s processed food or food groups or other components, I say that’s an attitude of privilege – the people who have enough money and ability to acquire food choices.

To feed the world, we need to take advantage of every trick, including processing, to feed the masses and reduce waste. Something like half the food that can be harvested from the field is currently wasted. Processing can help with that.

For more information on processed foods, check out these posts:

Are Processed Foods Unhealthy?

Reappraising Processed Foods

Is Processed Food Dangerous?

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