01/19/2018
By Karen Angelo

Highly processed foods are known to contribute to obesity, high blood pressure and Type 2 diabetes. Now there’s something else to worry about – brain function. 

Prof. Katherine Tucker of the Department of Biomedical and Nutritional Sciences has received a $3.9 million grant from the National Institutes of Health to study the effects of highly processed foods on cognitive decline. 

The five-year study aims to find out if consuming processed foods such as white rice, soda, frozen meals and deli meat contributes to dementia. 

“In the U.S. today, people tend to be deficient of nutrients such as magnesium, potassium and vitamin B6 due to the consumption of highly processed foods that lack necessary nutrients and overload on others,” says Tucker, a professor of nutritional epidemiology and director of the university’s Center for Population Health. 

Tucker and her research team will study roughly 700 participants of the Boston Puerto Rican Health Study Projects. The researchers have been following the nutrition and health risk factors of 1,500 Puerto Ricans living in the Boston area for a series of in-depth studies that began 12 years ago. 

The team’s past research showed that vitamin B6 deficiency was associated with inflammation, oxidative stress, metabolic syndrome, diabetes and depressive symptoms in Puerto Rican adults. These health issues, says Tucker, are far more prevalent among lower-income populations, such as the cohort she is studying. 

“When you lack the resources to buy healthy foods, you buy the cheapest foods you can — which probably means they’re highly processed,” she says.

Vitamin B6 Too Low, Phosphorus Too High 

The researchers will study the effects of two nutrients in particular – phosphorus and vitamin B6 – on the brain. 

While the body needs phosphorus for energy, metabolism and other functions, too much of the nutrient is harmful. Food manufacturers add low-cost phosphate compounds to foods for many reasons, including to make food last longer, stay creamier and maintain juiciness. Both regular and diet colas also contain phosphorus. 

“We know that dietary phosphorus intake is on the rise in the U.S. population and that it may be contributing to cardiovascular disease and osteoporosis,” says Tucker. “Animal studies suggest that excess phosphorus may also negatively affect a hormone that protects the brain from aging.” 

While phosphorus intake tends to be too high in the U.S. population, vitamin B6 intake tends to be too low. 

Important for keeping the brain and nervous system functioning properly, vitamin B6 is easily lost when food manufacturers process foods and don’t add it back to enriched grains. Nonprocessed foods that contain vitamin B6 include nuts, seeds, beans, poultry, fish, potatoes and bananas. 

By using baseline, two-year and six-year follow-up data from the Boston Puerto Rican Health Study, researchers will analyze diet, nutritional biomarkers and change in cognitive function by adding new outcome measures. About 700 of the participants will return for a repeat battery of cognitive exams and about 350 for MRI scans of the brain, to assess relationships with brain size and cell losses. 

“We will quantify the associations between usual intake of processed foods, phosphorus and vitamin B6 in relation to cognitive decline and brain health,” says Tucker. “With the growing and aging Latino population in the U.S, the study results will provide critical information to improve our understanding of how to improve health in this high-risk population. 

“While nutrition deficiencies tend to be more common in this population, the results can be applied to everyone.”