- Researchers investigated the effects of ultra-processed foods such as pizza, white bread, and chocolate on cognitive performance in older adults.
- They found that ultra-processed foods are linked to reduced language and executive function in older adults without chronic illness.
- They noted that reducing consumption of ultra-processed foods may prevent cognitive decline and reduce dementia risk.
Ultra-processed foods (UPF) are increasingly replacing traditional diets based on minimally-processed and unprocessed foods worldwide.
In the United States, UPFs comprise 57% of the energy intake among the adult population and 67% among children and adolescents.
A new study published in the European Journal of Nutrition suggests that consuming ultra-processed foods may have a negative impact on cognitive performance in older adults.
The researchers from Australia conducting the study told Healthline they defined ultra-processed foods as those that undergo “several industrial processes that can’t be reproduced at home.”
They noted that these items contain little to no whole foods and typically include flavorings, colorings, emulsifiers and other cosmetic additives.
Examples include packaged snacks, chocolates, breakfast cereals, and pre-prepared dishes such as pies, pasta, and pizza.
That’s opposed to processed foods that the researchers defined as foods that commonly have added sugar, oil, or salt. The processing is used to increase the durability or enhance the “sensory qualities” of the food. Examples include canned veggies, fruits, legumes and salted, cured or smoked meats.
What the research revealed
Using a cross-sectional study, the team of researchers evaluated more than 2,700 participants who were 60 years or older.
The participants were part of the National Health and Nutrition Examination SurveyTrusted Source from 2011 to 2014. Each participant recalled what they ate in a 24-hour period on two nonconsecutive days.
The team used standardized, validated tests, including one that assesses Alzheimer’s disease. They concluded that consuming ultra-processed foods was associated with worse performances in one of the tests among older people who did not have pre-existing diseases.
Researchers told Healthline the findings suggest that decreasing ultra-processed foods may be a way to improve impaired cognition among older adults.
“Research indicates that diets that follow a Mediterranean Diet style, recognized by the high proportion of foods with anti-inflammatory and antioxidant properties, are associated with a reduced risk of age-associated cognitive decline and dementia,” said Barbara Cardoso, Ph.D., lead author of the study and a senior lecturer in nutrition, dietetics and food at Monash University in Melbourne, Australia.
“Foods consumed as part of these diets include fish, nuts, olive oil and vegetables,” she said.
Experts say these findings are consistent with what they’ve learned from other studies about diet and dementia.
“There is growing evidence that what we eat can impact our brains as we age and many studies suggest it is best to eat a heart-healthy, balanced diet low in processed foods and high in whole, nutritional foods like vegetables and fruits,” said Percy Griffin, Ph.D., director of scientific engagement for the Alzheimer’s Association.
“So, it’s not surprising that this paper found that a diet high in ultra-processed foods impaired cognition in older adults,” he told Healthline.
Another study published in the journal Neurology last year also suggested there were benefits from a Mediterranean diet on brain health.
The researchers concluded that their findings corroborated the view that a Mediterranean diet could be a ”protective factor against memory decline and mediotemporal atrophy,” or shrinkage ofthe lobe of the brain associated with Alzheimer’s.
A looming crisis?
The Centers for Disease Control and Prevention estimatesTrusted Source that nearly 6 million people in the United States have Alzheimer’s and related dementias.
By 2060, the number of people diagnosed with Alzheimer’s is predicted to rise to an estimated 14 million.
Communities of color could be affected the most. Cases among Hispanics could increase seven times over the current estimates. Among African Americans, cases could increase four times the current estimates.
In San Francisco, a new community-based program is designed to focus on known modifiable risk factors to help prevent dementia.
Posit Science along with the YMCA is launching a model “Brain Health Program” funded by the National Institutes of Health.
The program, which is expected to be in operation in 6 months, will offer classes to at-risk adults. Part of the training will focus on the diet and nutrition principles the YMCA has been using in its Diabetes Prevention Program.
“Eating a brain-healthy diet is a big part of the Brain Health Program,” said Henry Mahncke, Ph.D., the chief executive officer of Posit Science.
“The future of brain health and dementia prevention is changing what we do in our everyday life so we build healthy, resilient brains that keep going as long as our bodies keep going,” he told Healthline. “Just about everything we eat gets sent by the bloodstream up to our brains, and so it’s not surprising to brain health experts that what we eat matters for our brain health, our cognitive performance, and our risk of dementia.”
Does all this matter if the food is nutritious?
Chris van Tulleken based his experiment on ultra-processed foods. But some ultra-processed foods have health benefits.
The term ‘ultra-processed food’ “is part of an active area of debate amongst scientists”, according to the Food and Drink Federation’s Chief Scientific Officer, Kate Halliwell. She says some studies suggest the focus should be on the nutritional balance of our diet rather than the level of processing.
Another study found participants ate more calories when on an ultra-processed diet than on a non-processed diet that was matched in terms of fat, sugar and salt. Participants’ blood tests showed an increase in the hormone responsible for hunger and a decrease in the hormone that makes us feel full, among those eating a diet high in ultra-processed foods. Van Tulleken’s hunger hormone increased by 30 percent during his experiment, which may have encouraged over-consumption.