What are processed foods, and are they bad for us?

As the Medical Director of the Kansas Business Group on Health I’m sometimes asked to weigh in on hot topics that might affect employers or employees. This is a reprint of a blog post from KBGH:

Are Processed Foods Bad for Us?

We hear a lot about eating “real” foods and avoiding overly processed foods. Food writer Michael Pollan famously said his rules for the ideal diet were to 1) eat food, 2) not too much, and 3) mostly plants. He went so far as to say that any food with more than five ingredients, or an ingredient you can’t pronounce, is probably bad for you. But what’s the evidence that this is right?

Thanks to the work of investigators at the NIH, we have new evidence that processed foods should not make up the bulk of our diets. Researchers paid twenty volunteers to live in a research hospital for a month. Ten of them were men, and ten were women. The volunteers were randomly assigned to eat either an “ultra-processed” diet or an unprocessed diet for two weeks. The diets were identical in the number of calories and amount of nutrients like fat, sugar, protein, and fiber. The volunteers were observed closely for food intake, and frequent testing was done to determine how many calories they were burning.

An example “ultra-processed” meal was:

  • steak (Tyson)

  • gravy (McCormick)

  • mashed potatoes (Basic American Foods)

  • margarine (Glenview Farms)

  • corn (canned, Giant)

  • diet lemonade (Crystal Light) with NutriSource fiber (researchers had to add fiber to the drinks in the processed diet to match the fiber of the unprocessed diet)

  • low fat chocolate milk (Nesquik) with NutriSource fiber.

In contrast, the unprocessed meal on the same day was:

  • beef tender roast (Tyson)

  • rice pilaf (basmati rice (Roland) with garlic, onions, sweet peppers and olive oil)

  • steamed broccoli

  • side salad (green leaf lettuce, tomatoes, cucumbers) with balsamic vinaigrette (balsamic vinegar (Nature’s Promise)

  • orange slices

  • pecans (Monarch)

  • salt and pepper (Monarch)

In spite of having equal numbers of calories available to them at every meal and snack, the people eating the processed diet ate about 500 calories per day more than the people eating the unprocessed diet.

After two weeks each person in the study was “crossed over” to the opposite diet from what they’d started on. That is, the processed diet folks started eating the unprocessed diet, and vice-versa.

What the investigators found was dramatic. In spite of having equal numbers of calories available to them at every meal and snack, the people eating the processed diet ate about 500 calories per day more than the people eating the unprocessed diet. This showed up in their weight: the processed dieters weighed, on average, 2 pounds more at the end of two weeks than they did at the start of the diet. All their extra weight was in the form of fat.

This finding could have a real impact on your employees’ health. When you are thinking of food for a large function, or thinking of how to contract food in an on-site cafeteria, it may be worth looking at the NOVA food classification system and working to increase the availability of Group 1 foods, those that are “unaltered following their removal from nature.”

Examples of these would be:

  • vegetables

  • fruits

  • potatoes (fresh, packaged, cut, chilled, or frozen)

  • whole-grain wheat, oats and other cereals

  • eggs

  • fresh, chilled or frozen meat, poultry, fish and seafood

  • pasta, couscous, and polenta

  • milk or yogurt without added sugar

Bon appetit.