interesterified vegetable fat

About

What it is and where it shows up.

Interesterified vegetable fat is produced by rearranging (transposing) fatty acids on the glycerol backbone of vegetable-oil triglycerides, either chemically (using sodium methoxide as catalyst) or enzymatically (using lipase enzymes), to modify the fat's melting point and physical texture. It is widely deployed as a low-trans-fat alternative to partially hydrogenated oils in margarines, shortenings, bakery products, confectionery fats, and infant-formula fat blends.

Safety summary

The regulatory and scientific consensus.

Interesterified fats carry negligible industrially produced trans fatty acids and are therefore preferable to partially hydrogenated oils in that respect; however, human intervention trials have raised concerns that certain formulations—particularly stearic-acid-rich palm-based IEF—may raise postprandial blood glucose, lower HDL cholesterol, and adversely alter endothelial-function markers. No IARC classification exists, no ADI has been formally established by any major regulatory body, and the long-term cardiovascular and metabolic effects at habitual dietary intakes remain a subject of active scientific debate.

Regulatory landscape

What food-safety regulators have decided.

Jurisdiction	Status	Note
FSSAI (Food Safety and Standards Authority of India) (India)	Restricted	FSS (Labelling and Display) Regulations 2020 require mandatory front-of-pack declaration of trans fat and saturated fat content, plus mono-unsaturated, polyunsaturated, and omega-3 fatty acid quantities for all packages of interesterified vegetable fat.source
EFSA (European Food Safety Authority) (European Union)	Approved	Interesterified vegetable fats are not food additives under Regulation (EC) No 1333/2008 and carry no E-number; they are used as food ingredients subject to general food safety law under Regulation (EC) No 178/2002. EFSA monitors process contaminants such as 3-MCPD esters and glycidyl fatty acid esters that can form in refined vegetable oils used in interesterification (EFSA Journal 2016;14(5):4426).source
FDA (Food and Drug Administration) (United States)	Approved	Interesterified fats are regulated as food ingredients, not food additives. Individual interesterified fat products made from FDA-approved oils are self-affirmed or notified as GRAS; FDA GRN 000654 is an example where an enzymatically interesterified cocoa butter substitute (palm oil stearin + stearic acid) was accepted as GRAS. No category-wide ADI established.source

Who should approach with care

Whose guidance would steer them away.

Heart Disease — Human studies show stearic-acid-rich interesterified fats can lower HDL cholesterol and adversely alter circulating endothelial-function markers, potentially compounding cardiovascular risk.

Diabetes — Intervention data indicate that palm-based interesterified fats may raise fasting and postprandial blood glucose and impair insulin signalling, which is of particular concern for individuals with type 2 diabetes or insulin resistance.

Infants — Interesterified fats used in infant formula require careful sn-2 positional fatty acid matching (e.g. palmitic acid at the sn-2 position); inappropriate triglyceride structure can impair fat and calcium absorption in neonates.

Pregnancy — FSSAI regulatory documentation notes that maternal trans fatty acid intake (elevated by sub-optimal interesterification) may increase susceptibility to metabolic alterations in the offspring; high saturated-fat load from IEF products is an additional precautionary concern.

Ibd — High-fat processed food ingredients including interesterified fats are generally associated with promotion of intestinal inflammation; patients with IBD are advised to limit highly processed fat sources on precautionary grounds.

Research citations

The sources behind this verdict.

1FSSAI. FSSAI Proposal on Regulation of Trans Fatty Acids. fssai.gov.in
2FSSAI. Food Safety and Standards (Prohibition and Restrictions on Sales) Regulations – Version XI, 2025. fssai.gov.in
3FSSAI. Food Safety and Standards (Labelling and Display) Regulations 2020 – Compendium Version II, 2022. fssai.gov.in
4FDA. Agency Response Letter GRAS Notice No. GRN 000654 — Cocoa Butter Substitute via Enzymatic Interesterification, 2018. fda.gov
5PubMed. Stearic acid-rich interesterified fat and trans-rich partially hydrogenated soybean oil adversely alter circulating markers of endothelial function in healthy men, 2007. pubmed.ncbi.nlm.nih.gov

Independently researched5 citations