Tomato paste delivers 2.5 times more lycopene to the bloodstream than the same amount from a fresh tomato. The total absorption over time is 3.8 times higher. If you have ever simmered a red sauce and wondered whether cooking changes anything nutritionally, the answer is not small.
But the mechanism behind that number has two parts, and nearly every source that repeats the claim leaves one of them out.
Does Cooking Tomatoes Increase Lycopene Absorption?
Cooking tomatoes dramatically increases lycopene bioavailability, but only when fat is present in the same meal. Processing breaks cell walls and releases lycopene from its crystalline matrix (2.5x more reaches the blood from paste vs fresh). However, cooking without oil produced no significant increase in absorption. The fat is not optional.
— Gärtner et al. 1997 · Am J Clin Nutr · crossover trial | Fielding et al. 2005 · Asia Pac J Clin Nutr · n=23
Lycopene sits inside tomato cells locked in a crystalline structure. Raw, those crystals pass through the gut mostly intact. Heat and mechanical processing (crushing, cooking, industrial concentration into paste) break the cell walls and dissolve the crystal matrix, releasing lycopene molecules into a form the intestine can actually interact with.
That release is step one. A human crossover trial measured it directly: participants ate the same dose of lycopene from fresh tomatoes and from processed paste, both with fat. The paste group showed 2.5 times the peak blood concentration and 3.8 times the total amount absorbed over the following hours. The difference was measured in the chylomicron fraction, the transport particles the gut produces specifically for fat-soluble nutrients.
Step one makes lycopene available. Step two determines whether it actually enters the blood.
A randomized trial cooked 470 grams of tomatoes two ways: with 25 milliliters of olive oil, and without. The group that cooked with oil saw an 82% increase in plasma lycopene. The group that cooked without oil saw no significant increase in trans-lycopene at all.
That second result is what nearly everyone leaves out. Heat freed the lycopene from the cells. The intestine still could not absorb it without a fat carrier. Lycopene is fat-soluble, which means it dissolves in lipid, not in water. Without fat in the same meal, the freed molecules pass through unabsorbed, the same way they would have passed through raw.
The two mechanisms work in sequence: processing breaks the container, fat provides the vehicle. Skip either step and the benefit collapses. A tomato soup made with water and no oil delivers the flavor of cooked tomatoes without the absorption advantage. A raw tomato drizzled with olive oil provides the fat carrier but leaves most lycopene locked in its crystalline cage.
Your pasta sauce, your shakshuka, your tomatoes roasting on a sheet pan in olive oil: those are doing both. The combination of heat and fat is what makes dietary fat more than a calorie source in meals like these.
One honest caveat. The trial that isolated the oil effect used a generous amount: 25 milliliters per 470 grams of tomato. Most home cooks use less oil per volume of tomato. The mechanism is the same at smaller doses, but the magnitude likely scales with fat quantity. A thin film of oil is not zero, but it is not 25 milliliters either.
The next time someone tells you cooking tomatoes increases lycopene, they are half right. Cooking frees it. Fat absorbs it. One without the other is a sentence without a verb.
