GLOSSARY

Omega Fatty Acids are named from the first double bond at the methyl end; omega-3, omega-6 and omega-9 are distinct families.

The omega number locates the first double bond from the methyl end, which differs from the carboxyl end. Total carbon number and total double bonds are separate information. Omega therefore names a structural family rather than a quality score or speed of action; members can differ in length, food sources and function.

In fatty-acid notation, the number before the colon usually gives carbon count and the next number gives double-bond count. An omega family or bond position may follow. This is not an intake weight or recommended dose. Distinguishing some isomers also requires specifying bond positions and spatial geometry beyond the basic code.

Saturation concerns carbon–carbon double bonds in a fatty-acid chain, not fullness after eating or a food's energy content. One double bond defines monounsaturation; multiple bonds define polyunsaturation. Their positions and cis or trans geometry also matter, so counting bonds alone cannot explain every physical property or biological effect.

Linoleic and alpha-linolenic acids are essential because humans cannot synthesise their structures from scratch. Essential means that a dietary supply is needed, not that unlimited amounts are beneficial. Different oils, nuts and seeds contribute to this supply. Severely removing all fats can make adequate intake of these fatty acids difficult.

The body can convert some alpha-linolenic acid into EPA and DHA, but conversion is limited and varies between people and conditions. A gram of the precursor is not equivalent to a gram of either product. Walnuts and flaxseed remain useful foods; direct provision requires separately considering fish or an appropriate algal product.

Omega-6 includes essential dietary fatty acids and should not be labelled uniformly inflammatory or harmful. Fatty-acid-derived mediators have diverse, tissue-dependent actions. Replacing saturated fat with suitable unsaturated sources differs from adding unlimited oil. Interpretation should therefore reflect the food pattern and actual intake rather than treating an entire family as a toxin.