Trans Fat Consumption May Impair Memory

A diet rich in trans fatty acids may be harming the brain and impairing memory, according to new research presented at the American Heart Association’s Scientific Sessions 2014. 

Investigators looked at the dietary habits of 1,018 healthy men and found those who consumed the most trans fats had notably worse performance on a word memory test. The strength of the association remained even after adjustment for several variables.

“We previously found that chocolate consumption, which is antioxidant and cell energy supportive, was linked favorably to memory in young adults,” said lead study author Beatrice Golomb, MD, PhD, Professor of Medicine at the University of California, San Diego. “We reasoned that since trans fats conversely are prooxidant and energy adverse that they might be linked adversely to memory function in the same age group.”

She also said trans fat consumption has been linked to greater BMI and greater risk for coronary artery disease (CAD).  

Dr. Golomb, who presented the study findings at the meeting, said trans fats increase the shelf life of foods, but they reduce the shelf life of people.

“We affirmed that adjustment for blood pressure, waist circumference and BMI, though not lipids or glycemic variables, attenuated the relationship of trans fats to memory. This is consistent with these metabolic factors either being in the mediating pathway or else linked to mediating mechanisms,” Dr. Golomb told Endocrinology Advisor. 

“We think oxidative stress and impaired cell energy, which are known to predispose to metabolic syndrome variables, are promoted by trans fats, and are adverse to memory.”

The researchers analyzed data on men aged 20 years and older (n=694) and postmenopausal women without CAD. They estimated trans fat consumption based on dietary questionnaires completed by the participants. 

To evaluate memory, each participant was presented with a series of 104 cards showing words and had to state whether each word was a new word or a word duplicated from a prior card.

The researchers found that among men aged younger than 45 years, those who ate more trans fats had significantly poorer performances on the word memory test. The strength of the association remained even after adjusting for age, education, ethnicity and depression. 

The study suggested that each additional gram a day of trans fats consumed was associated with an estimated 0.76 fewer words correctly recalled.  This translated to an estimated 11 fewer words (>10% reduction in words remembered) for those eating the highest amounts of trans fats compared with adults who ate the least trans fat.

The average number of words correctly recalled was 86.

“We found that the higher the trans fat consumption, the worse the memory performance in younger adult ages, during key career building years. The relation was robust across models adjusting for potential confounders,” said Dr. Golomb. “We think prooxidant effects and cell energy impairment may underlie this. Oxidative stress impairs endothelial function and blood flow, which reduces oxygen and glucose delivery.”

She said the brain is especially vulnerable to these influences.

Currently, the FDA is taking steps to reduce the amount of artificial trans fats in the U.S. food supply.

Reference

1. Golomb BA et al. Abstract 15572. Presented at: American Heart Association’s Scientific Sessions 2014; Nov. 15-19, 2014; Chicago.