If women drink a small glass of tomato juice or eat a bowl of carrots every day, they reduce their risk of breast cancer by three-quarters or two-thirds, respectively. This is suggested by an epidemiological study from Iran.

Study
In 2025, epidemiologists from Isfahan University of Medical Sciences published an observational case-control study in Nutrition & Metabolism, involving 1,200 women.

Half of the women had recently been diagnosed with breast cancer. The other half were women without breast cancer who were similar in many other respects to the women in the other group.

All women completed questionnaires about their diet, which allowed the epidemiologists to estimate how many carotenoids they consumed.

The researchers then divided the women into four roughly equal-sized groups based on their daily carotenoid intake. They then examined whether a relatively high carotenoid intake altered the risk of breast cancer.

Using statistics, the researchers removed the influence of other dietary factors, age, gender, BMI, physical activity, smoking and socioeconomic status.

Results
The most powerful protective factor the Iranians found was lycopene intake. A high lycopene intake [Q4] reduced the risk of breast cancer by 77 percent compared to the lowest intake [Q1].

Two other carotenoids with a strong protective effect were phytoene and phytofluene. This isn't really surprising. Phytoene and phytofluene have a chemical structure very similar to lycopene.

Click on the tables below for a larger version.

Lutein, zeaxanthin, and beta-carotene also offered some protection, but not as much as lycopene, phytoene, and phytofluene. Alpha-carotene, beta-cryptoxanthin, astaxanthin, neoxanthin, and violaxanthin did not protect.

Lycopene
It's surprisingly easy to get enough lycopene to qualify for Q4 - the group with the highest lycopene intake. A tablespoon of tomato paste or a small glass of tomato juice contains enough lycopene. The tables below show this. Click on them for a larger version.

Lycopene is actually only found in significant amounts in tomato products.

Phytoene & phytofluene
Phytoene and phytofluene are found in orange fruits and vegetables, such as apricots, pumpkin, oranges, and especially carrots. The tables below summarize how much of these products you need to eat daily to reach Q4.

Mechanism
The researchers believe that lycopene, phytoene, phytofluene, and other carotenoids reduce inflammatory responses by downregulating NF-kappaB. This makes it more difficult for cancer cells to spread throughout the body.

At the same time, carotenoids activate Nrf2, a genetic switch that allows cells to produce more protective antioxidants. This reduces the chance that genetic damage will transform cells into cancer cells.

We, the clueless compilers of this free web magazine, have another theory. Carotenoids like lycopene make NK cells more robust, allowing them to eliminate more cancer cells.

Conclusions
"These findings suggest that encouraging the consumption of carotenoid-rich fruits and vegetables could be an accessible and practical strategy for breast cancer prevention and may provide supportive evidence for incorporating carotenoid intake into dietary guidelines," the Iranians summarize.