Harmful fat found in some junk food linked to major dementia risk

Eating trans fats has been linked to a startling high increase in the risk of developing Alzheimer's disease, underscoring the importance of eliminating this ingredient from food products. The study comes from Kyushu University Hospital Fukuoka, where researchers tracked more than 1,600 older adults for a decade, finding that trans fats consumption was 'significantly associated' with developing dementia.

Trans fats is the term used to refer to artificial trans-unsaturated fatty acids (aka, partially hydrogenated oils), an ingredient that used to be considered generally safe for use in food. As a result of that designation, many food products — particularly fast food, junk food, and prepackaged foods — sold in the US contained trans fats as an ingredient.

A number of concerning studies, however, as well as an eventual change of tune by the FDA in 2013, resulted in a crackdown on the ingredient, which is largely regarded as a public health risk. The use of artificial trans fats in food products has decreased drastically in light of the health concerns, but they are still used in some junk food and by some restaurants as a cheap alternative to other safer oils.

The American Heart Association notes that artificial trans fats cause an increase in 'bad' LDL cholesterol and a decrease in 'good' HDL cholesterol, increase one's risk of developing type-2 diabetes, and also raise stroke and heart disease risk. According to a study recently published in Neurology, these oils may also greatly increase one's risk of developing dementia later in life.

The study followed 1,628 Japanese adults ages 60 and older for a little over a decade, finding that during that time, 377 of the participants developed some variety of dementia. The researchers found that higher levels of the trans fat elaidic acid were 'significantly' linked to an increased risk in developing all-cause dementia despite other risk factors.

The researchers found that this increased risk persisted regardless of how much the participants ate, including their consumption of polyunsaturated and saturated fats. The majority of the affected participants had developed Alzheimer's disease, with the remainder having developed vascular dementia.