A diet high in trans fats linked to a significantly higher risk of dementia among the elderly

Trans fatty acids, or trans fats, are unhealthy substances found in processed foods. They have been linked to a high risk of heart disease, stroke and heart attack. But little is known about the possible association between trans fats and dementia, or a decline in cognitive functions.

Now, new research from Japan has found that older adults who have high levels of trans fats in their blood also have a 52 to 74 percent higher risk of developing dementia. Published in the journal Neurology, the study also reveals that foods such as sweet pastries, margarine and sugar confectioneries are the biggest contributors to high trans fat levels in the blood.

Trans fats linked to a higher risk of dementia

The Japanese study involved 1,628 participants aged 60 and older who are residents of the town of Hisayama. They were all part of the ongoing Hisayama Study, which aims to evaluate risk factors for lifestyle-related diseases.

None of the participants had dementia when they gave blood samples during a screening exam that took place from 2002 to 2003. Ninomiya and his colleagues from Nakamura-Gakuen University determined the participants’ trans fat levels by measuring the amount of elaidic acid in their blood samples.

Elaidic acid is a major trans fat commonly found in partially hydrogenated vegetable oils. Milk and some meat products also contain small amounts of elaidic acid. The researchers divided the participants into four groups based on their blood levels of trans fats and asked them to answer questionnaires about their food intake.

The researchers followed the participants for an average of 10 years, during which 377 of them developed some form of dementia. Of these 377 participants, 247 were diagnosed with Alzheimer’s disease, while the rest had vascular dementia. Of the 407 participants with the highest levels of trans fats, 104 developed dementia. This translates to an incidence rate of 29.8 per 1,000 person-years.

Meanwhile, 103 of the 407 participants in the group with the second-highest trans fat levels also developed dementia. This translates to an incidence rate of 27.6 per 1,000 person-years. As for the group with the lowest levels of trans fats, the incidence rate was found to be 21.3 per 1,000 person-years.

When the researchers adjusted for factors that could influence the risk of dementia — such as smoking, high blood pressure and diabetes — they found that participants with the highest trans fat levels had a 52 percent higher chance of developing dementia than those with the lowest levels. Meanwhile, participants in the second-highest group had a 74 percent higher chance of developing dementia than those in the lowest group.

The researchers also evaluated questionnaire responses to see which foods contributed the most to high blood levels of trans fats. Sweet pastries turned out to be the strongest contributor. Other culprits were sugar confectioneries like candies and caramels, as well as croissants, non-dairy creamers, ice cream and rice crackers.

When the researchers adjusted for other dietary factors, such as total energy intake and intake of saturated and polyunsaturated fatty acids, they found that the link between trans fat levels and dementia remained significant. These findings clearly link unhealthy trans fat levels to yet another disease — one that severely affects quality of life, especially among older adults.

In 2018, the Food and Drug Administration (FDA) banned artificial trans fats. But because of a provision in the ban, food manufacturers can still label their products “zero trans fat” so long as they contain less than 0.5 grams. If you wish to avoid the negative consequences of consuming trans fats, avoid processed foods, cut down on your meat consumption and enrich your diet with fresh fruits, vegetables, whole grains, seeds and nuts. (Related: Trans fat ban linked to drastic drop in heart attacks and stroke, finds new study.)

For more articles about foods and food components you’re better off avoiding, visit StopEatingPoison.com.

Sources include:

MedicalNewsToday.com

N.Neurology.org

AAN.com