A new study just out from the US National Institutes of Health (NIH) confirms what many of us have long suspected about processed foods and weight gain. While we still don't know the mechanism behind it, the study proves once and for all that processed foods lead to weight gain because people eat more of them. The study underscores why fitness nutrition is so important to us.
The Daily Mail reports that the NIH conducted their study with the cooperation of 20 volunteers who agreed to maintain tightly controlled diets throughout. The volunteers were divided into two groups, one receiving a diet consisting of highly processed foods while the other being fed with nothing but unprocessed foods. After two weeks, the groups switched diet plans.
Shockingly, almost all of the participants gained upwards of 2 pounds in the two weeks they were eating processed foods. They lost the same amount of weight on the unprocessed diet. Researchers say that this proves the correlation between processed foods and weight gain, despite the small sample size.
What They Ate
The meal plan for processed foods included things like dry breakfast cereal served with enriched milk, pre-packaged blueberry muffins, crisps, etc. Many of the foods where high in both calories and sugar.
Researchers noted that the volunteers tended to eat more food when on the processed diet. In fact, participants consumed over 500 calories more per meal. They also ate their meals faster than the unprocessed group.
The meal plan for unprocessed foods contained plenty of fresh fruits, vegetables, and grains. A typical lunch would include chicken salad, blueberries, almonds, and milk. Researchers said that the participants ate just about as much as was expected when they were on this plan.
Speed Could Be the Issue
Although the researchers are not sure, they suspect that the speed at which people consume their food may contribute to weight loss. This is rooted in the knowledge that it takes a certain amount of time for the brain to recognise that the stomach has food in it.
Researchers explained that processed foods don't require as much effort to eat. You don't have to chew as much for example, so you're likely to swallow processed foods more quickly. This leads to taking the next bite, swallowing again, and so forth. You're able to eat more food before your brain tells you your stomach is full.
By contrast, unprocessed foods require more effort. You have to chew longer and be more careful about swallowing. You have to take smaller bites as well. This gives your brain time to catch up, letting you know you are full sooner. The thinking is that you eat less this way.
Regardless of the mechanism, we now have incontrovertible proof that processed foods lead people to eat more and gain weight. It's yet another reason to focus on fitness nutrition and unprocessed foods as a means of losing weight and keeping it off.
Sources:
Daily Mail – https://www.dailymail.co.uk/health/article-7036805/Processed-foods-pizza-make-people-eat-fast-gain-weight-study-shows.html
