Are There Different Types of Lycopene? Yes, and Here's What You Need to Know

December 12, 2025 •

2 min read

While many people assume lycopene is a single compound, research shows it actually exists in several different forms known as isomers. The most common variations are the trans-lycopene and cis-lycopene forms, which possess distinct molecular shapes and physiological effects in the human body.

Quick Summary

Lycopene is not a single compound but exists as different isomers, most notably the highly stable all-trans form and various, more bioavailable cis versions, which are influenced by processing and digestion.

Key Points

Isomer Types: Lycopene primarily exists as two geometrical isomers: the straight all-trans form found in raw foods and the bent cis form, which is more common in processed products and human tissues.
Bioavailability: Cis-lycopene isomers are significantly more bioavailable and easily absorbed by the body than the all-trans isomer due to their higher solubility.
Processing Matters: Cooking, especially with a little oil, enhances lycopene absorption by converting the less soluble trans isomers into the more accessible cis forms.
Sources Vary: Different foods contain different ratios of lycopene isomers; for example, red tomatoes are high in all-trans, while tangerine tomatoes are naturally rich in a specific cis isomer.
Balanced Intake: For optimal absorption, it is beneficial to consume a mix of both raw and cooked lycopene-rich foods alongside some dietary fat.
Supplement Forms: Lycopene is available in supplements as synthetic, extracted, or in combination with other tomato nutrients as a standardized extract.

The Core Difference: Trans vs. Cis Isomers

Lycopene's structure, a long carbon chain with double bonds, allows for variations in shape, creating different isomers like the linear all-trans and bent cis forms. These structural differences influence properties like color, stability, and bioavailability. While raw plants primarily contain all-trans lycopene, processing and digestion convert it into the more easily absorbed cis isomers.

All-Trans Lycopene: The Stable Form in Raw Foods

All-trans-lycopene is the dominant and most stable form found in fresh, raw fruits like tomatoes and watermelon. Its linear shape leads to crystallization within plant cells, making it less bioavailable from unprocessed foods.

Cis-Lycopene: The Bioavailable Form for the Body

Cis-lycopene isomers have a bent shape, making them more soluble in lipids and easier to absorb in the small intestine. Conversion to cis-lycopene occurs through: heat processing of foods like tomatoes, digestion in the stomach, and naturally in some varieties like tangerine tomatoes which contain tetra-cis-lycopene (prolycopene). Absorbed cis-lycopene, particularly 5-cis-lycopene, accumulates more readily in blood and tissues.

Comparison of Lycopene Isomers


Feature	All-Trans Lycopene	Cis-Lycopene Isomers
Molecular Shape	Linear and rigid	Bent, twisted, and shorter
Thermodynamic Stability	Most stable form	Less stable than all-trans
Bioavailability	Lower absorption by the body	Higher absorption by the body, more soluble in bile micelles
Common Dietary Sources	Raw red tomatoes, watermelon	Processed tomato products (sauce, paste)
Prevalence in Foods	Predominant form in fresh foods	Proportion increases with heat processing
Prevalence in Human Tissues	Lower proportion relative to diet	Higher proportion relative to diet

The Role of Isomerization in Lycopene Bioavailability

Effective lycopene utilization requires its release from food and incorporation into digestive micelles. The crystalline nature of all-trans-lycopene hinders this from raw foods. Heating foods like tomatoes breaks down cell walls and converts trans to more soluble cis isomers, significantly increasing bioavailability. Consuming lycopene-rich foods with dietary fat further aids absorption by stimulating bile acid release for micelle formation.

Supplementation Forms and Considerations

Lycopene supplements offer alternative options and are available in various forms, including synthetic lycopene with specific isomer ratios, extracted lycopene from natural sources, and standardized tomato extract containing other natural tomato nutrients.

Conclusion: Maximizing Lycopene Absorption

Understanding lycopene isomers highlights the importance of food source and preparation for maximizing benefits. While all-trans is stable in nature, cis isomers are better absorbed. A mix of raw and cooked lycopene-rich foods, consumed with healthy fats, is ideal for broad isomer intake. Cooked tomato products offer superior cis-lycopene absorption.

For more on lycopene bioavailability from different sources, see this study: Enhanced bioavailability of lycopene when consumed as cis-isomers from tangerine tomatoes.

Frequently Asked Questions

The main difference is their molecular shape and bioavailability. Trans-lycopene has a linear shape, is more stable, and is found in raw foods, but it is less bioavailable. Cis-lycopene has a bent shape, is more soluble, and is more easily absorbed by the body.

Yes, heat processing helps to convert the less bioavailable all-trans-lycopene in raw tomatoes into the more readily absorbed cis-lycopene isomers.

The bent molecular structure of cis isomers makes them more soluble in the bile acid micelles formed during digestion. This enhanced solubility allows for more efficient absorption into the bloodstream and tissues.

Not necessarily. While supplements can provide specific lycopene isomer ratios, consuming lycopene from whole foods like tomatoes, watermelon, and papaya also provides other beneficial nutrients. Processed tomato foods often provide higher bioavailability than raw foods.

Excellent sources of cis-lycopene include processed tomato products such as tomato paste, ketchup, and sauces. Tangerine tomatoes also contain a naturally high concentration of tetra-cis-lycopene.

After ingestion, lycopene is incorporated into bile acid micelles with the help of dietary fat. It is then absorbed by intestinal cells and packaged into chylomicrons for transport, during which isomerization from trans to cis forms continues.

You can improve lycopene absorption by consuming lycopene-rich foods with some dietary fat, such as adding olive oil to tomato sauce. Cooking also helps break down cell walls and enhances the formation of more bioavailable cis isomers.