Alzheimer's disease & dementia

Serum elaidic acid levels tied to dementia, Alzheimer's disease

Higher serum levels of elaidic acid, an objective biomarker for industrial trans fat, are associated with an increased risk for developing all-cause dementia and Alzheimer disease, according to a study published online Oct. ...

Oncology & Cancer

Scientists remind immune cells whose side they should be on

International group of scientists in the joint study of the laboratory of the Wistar Institute, University of Pittsburgh, and I.M. Sechenov First Moscow State Medical University discovered the change in activity of one of ...

Health

Foods to lower your cholesterol count

(HealthDay)—It's not always possible to lower cholesterol through diet alone—sometimes there's no way to override your DNA, and medication becomes a must.

Health

The skinny on fats

(HealthDay)—Even when you're trying to lose weight, you need some fat in your diet for good health. While fat in general has gotten a bad rap, some types of fat—particularly plant-based fats—are good for you in moderation.

Health

High omega-6 levels can protect against premature death

Could omega-6 fatty acids protect you against premature death? The answer is yes, according to a new University of Eastern Finland study. While protecting against death, omega-6 fatty acids also keep cardiovascular diseases ...

Immunology

Polyunsaturated fatty acids linked to reduced allergy risk

New research from Karolinska Institutet in Sweden reveals that high levels of polyunsaturated fatty acids in children's blood are associated with a reduced risk of asthma or rhinitis at the age of 16 years. The study is published ...

Medical research

Discovery challenges belief about brain's cellular makeup

A discovery made by Junhwan Kim, PhD, assistant professor at The Feinstein Institute for Medical Research, is challenging science's longstanding beliefs regarding the cellular makeup of the brain. This breakthrough was outlined ...

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Polyunsaturated fat

In nutrition, polyunsaturated fat is an abbreviation of polyunsaturated fatty acid. That is a fatty acid in which more than one double bond exists within the representative molecule. That is, the molecule has two or more points on its structure capable of supporting hydrogen atoms not currently part of the structure. Polyunsaturated fatty acids can assume a cis or trans conformation depending on the geometry of the double bond.

The lack of the extra hydrogen atoms on the molecule's surface typically reduces the strength of the compound's intermolecular forces, thus causing the melting point of the compound to be significantly lower. This property can be observed by comparing predominately unsaturated vegetable oils, which remain liquid even at relatively low temperatures, to much more saturated fats such as butter or lard which are mainly solid at room temperature. Trans fats are more similar to saturated fat than are cis fats in many respects, including the fact that they solidify at a lower temperature.

A fatty acid has a carboxylic acid at one end and a methyl group at the other end. Carbon atoms in a fatty acid are identified by Greek letters on the basis of their distance from the carboxylic acid. The carbon atom closest to the carboxylic acid is the alpha carbon, the next adjacent carbon is the beta carbon, etc. In a long-chain fatty acid the carbon atom in the methyl group is called the omega carbon because omega is the last letter of the Greek alphabet.

Omega-3 fatty acids have a double bond three carbons away from the methyl carbon, whereas omega-6 fatty acids have a double bond six carbons away from the methyl carbon. The illustration below shows the omega-6 fatty acid, linoleic acid.

This text uses material from Wikipedia, licensed under CC BY-SA