Last Updated on August 1, 2021 by Max
Lycopene, belonging to the carotenoids, is abundantly found in tomatoes and tomato-based products, pink grapefruit, and watermelon. Asparagus and parsley despite not having red or orange color, also are good sources of lycopene.
Lycopene is a potent antioxidant-an important deactivator of reactive oxygen species. The human body cannot synthesize lycopene and therefore, it must be consumed with daily food. The absorbed lycopene is mostly stored in the testes, liver, adrenals, and prostate, with concentrations in the testes as high as 10 times that of other tissues. This may point to an exclusive biological role of lycopene in certain tissues.
Lycopene content in different foods.
Tomato and tomato-based products account for approximately 80% of lycopene consumption.
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Lycopene reduces the risk of prostate cancer.
Lycopene is efficient in improving cancer conditions, prostate, lung, stomach, breast, and ovary cancers, in particular.
The study by Giovannucci E, et al. (1995) tested different types of carotenoids to the risk of prostate cancer. They found no association with the intake of beta-carotene, alpha-carotene, lutein, beta-cryptoxanthin, or dietary retinol with risk of prostate cancer, whereas only lycopene intake resulted in lower risk (age- and energy-adjusted RR = 0.79; P = .04). What is interesting, of 46 vegetables and fruits or related products, they found three sources of lycopene that notably lowered prostate cancer risk: tomato sauce (P= .001), tomatoes (P = .03), and pizza (P = .05).
Meta-analysis of twenty-six high-quality studies, including 17,517 cases of prostate cancer showed that higher lycopene consumption significantly lowered prostate cancer risk. An interesting finding of the study was that the content of lycopene in blood between 2.17 and 85 μg/dL was linearly associated with a reduced risk of PCa with a threshold between 9 and 21 mg/day.
Other health benefits of lycopene.
The beneficial properties of lycopene have also been shown to diabetes, cardiovascular diseases, inflammatory events, skin, bone, hepatic, neural, and reproductive disorders.
As to reproductive disorders, health benefits of lycopene have been revealed in decreased sperm DNA fragmentation and lipid peroxidation and improved sperm motility and mitochondrial enzymatic activity, and increased sperm count. Human trials have reported the raised pregnancy rates with supplementation of 4–8 mg of lycopene daily for 3–12 months. Treatment of men with infertility, caused by low sperm quality, resulted in six pregnancies in 26 patients (23%) (Gupta NP, Kumar R. 2002). So, the results of these trials show that a daily dose of 4–8 mg of lycopene which is equal to the intake of approximately 100 g of tomato sauce or 100 g of watermelon for 3-12 months, is sufficient to treat male infertility.
The other studies suggest this carotenoid supports mental longevity (Crowe-White KM et al. 2019).
The main health-protecting effects of lycopene are exposed through anti-oxidative, free-radical scavenging, and antiapoptotic activities. Moreover, this miracle plant pigment prevents bacterial toxins, mycotoxins, fluoride, metals, and pesticides from exerting their toxicities against the human body.
It should be noted that age and some chronic diseases such as CVD can lower the bioavailability of this health guard. Therefore, it should be supplemented by various means, such as grapefruit or watermelon juices, or tomato sauce.
Bioavailability if lycopene.
Humans cannot absorb all the lycopene available in foods, just only about 10%–30%, the rest is excreted.
The factors helping in the absorption of lycopene are:
- Food (tomato) heating and processing leads to the breakdown of the food matrix, hence making lycopene more bioavailable;
- Trans isomers of lycopene are much less absorbable than cis-isomers. Heating and processing transform trans to cis forms increasing the absorption of lycopene into the body by up to 2.5 times.
- Due to its lipophilic nature, the absorption of lycopene is improved when it is consumed with other fats in the diet or cooked in an oil medium.
The recommended doses of lycopene.
There is no ideal daily lycopene dose that could be recommended for everybody. It depends primarily on the age and health status of a person. According to studies in this area, the suggested daily lycopene intake can be from 2 to 20 mg (Saini RK. et al. 2020).
Lycopene intake as low as 6.5 mg/day was found effective against prostate cancer in men (Giovannucci E, et al. 1995). However, it should be raised to 10 mg/day, in the case of advanced prostate cancer.
Toxicity of lycopene.
Ordinary doses of lycopene have not been found to cause any adverse effects in human studies, even at the level of 3 g per day/kg of body weight. The suggested dose of lycopene intake is much less than this level.
Because of the strong antioxidant effects of lycopene, precautions should be taken for patients under chemo and radiation therapy; it has the potential to interfere with those therapies.
There was a case study in the literature, of liver lycopenemia in a lady who drank two liters of tomato juice every day for many years. Interestingly, this did not negatively affect her liver function, but only led to an unusual discoloration of normal skin color. Three weeks after stopping the consumption of tomato juice, the normal color of the skin was restored.
Of course, these are extremes, but if you are at risk for prostate cancer, it would be wise to include lycopene-rich foods in your daily menu, in particular tomatoes, tomato sauces, and especially tomato ketchup. It should be borne in mind that the tomatoes that we have on the shelves are usually collected green and turn red in the dark without access to sunlight. Therefore, it is much more useful to use them after heat treatment in the form of ketchup or sauces.
- M. Imran et al. Lycopene as a Natural Antioxidant Used to Prevent Human Health disorders. Antioxidants (Basel). 2020 Aug 4;9(8):706.
- Giovannucci E, et al. Intake of carotenoids and retinol in relation to risk of prostate cancer. J Natl Cancer Inst. 1995 Dec 6; 87(23):1767-76.
- P. Chen et al,2015. Lycopene and Risk of Prostate Cancer. A Systematic Review and Meta-Analysis. Medicine (Baltimore). 2015 Aug; 94(33): e1260.
- Mozos I, et al. Lycopene and Vascular Health. Front Pharmacol. 2018; 9():521.
- Crowe-White KM, Phillips TA, Ellis AC. Lycopene and cognitive function. J Nutr Sci. 2019; 8():e20.
- Corridan B., O’Donohue M., Morrissey P. Proceedings of Proceedings-Nutrition Society of London. Cambridge University Press; Cambridge, UK: 1998. Carotenoids and immune response in elderly people; p. 4A.
- Saini RK. et al. Protective effects of lycopene in cancer, cardiovascular, and neurodegenerative diseases: An update on epidemiological and mechanistic perspectives. Pharmacol Res. 2020 May; 155():104730.
- Gupta NP, Kumar R. Lycopene therapy in idiopathic male infertility–a preliminary report. Int Urol Nephrol. 2002; 34(3):369-72.