Everybody today is promoting whole foods compared to processed foods. Many terms like ‘whole grain’, ‘clean eating’, ‘all natural’, ‘functional’ and ‘local’ have been taken over the lexicon. However, until recently there has been little scientific evidence to support the eat whole food movement.
The British Medical Journal published two studies of populations that found a lower risk of heart diseases and greater longevity among adults who ate less processed food. A further study by the National Institute of Health (NIH) showed that eating ultra-processed foods results in higher calorie intake and weight gain when compared to the ones with minimum consumption of processed food. The paper published by NIH explains the benefit of whole foods and acknowledges that ultra-processed food makes important contributions to the nation’s diet.
The paper was published by Kevin Hall who is a mathematical modeler and global obesity expert. It enrolled 20 young healthy adults( 10 men and 10 women ) who agreed to a clinical setup and testing for 28 days which provided access to food given only by the clinic. The results showed that persons gained 500 more calories per day when given ultra-processed food. It resulted in two pounds of weight gain in just 14 days. On the other hand, people who changed from ultra-processed food to minimally processed foods lost two pounds in 14 days. The data suggest that ultra-processed foods lead to more energy intake and weight gain whereas minimally processed food leads to low energy intake and weight loss.
The weight gains occurred even after the investigators tried to make both the meals alike with the same percentages of carbohydrates, proteins, fats, sugars, sodium, etc. It was achieved by adding soluble fiber to beverages for ultra-processed meals and making sure that the minimally processed diet included plenty of fresh fruit, high in natural sugars. The ultra-processed food contained canned soups and grains in a pouch. So, the ultra-processed food which was used was not that junky. If the ultra-processed diets were made to vary in nutrient intake then there would be a larger difference in calorie intake. The ultra-processed foods are formulated with industrial ingredients and contain little or no intact food. Ultra-processed foods are soft and easier to chew, swallow which led to calories being consumed 50% faster than minimally processed foods.
When we eat quickly our calorie consumption may race ahead of the gut-brain connection. This is because it takes 20 minutes for the gut to release hormones telling the brain that it is full. Insoluble fiber which is included in minimally processed foods moves through the stomach and GI system without breaking down and being absorbed which leads to reduced calorie absorption. Processed food is 60% cheaper than unprocessed food and offers convenience in hyper-speed world. We must choose the food and eat them either in whole or in the minimum processed form.