Antioxidants you find in the red of tomatoes and the yellow plant pigments in carrots  are called carotenoids. You also find them in green leafy vegetables They belong to the family of phytonutrients. See also my article: Phytonutrients, compounds from the garden.
These carotenoids are powerful antioxidants to fight against heart disease and certain forms of cancer.

Research has shown promising results from a number of carotenoids, particularly lycopene
(also found in tomatoes), lutein (found in vegetables such as spinach and kale), and
zeaxanthin ( found in dark green leafy vegetables). All three play a powerful role as antioxidants  in cancer prevention.

Researchers in the Tufts University Carotenoids Health Laboratory say: “Skipping fruits &
vegetables is part of the classic “profile” of people who develop cancers of the head and
neck, but that increasing your intake of these antioxidants rich products may cut your risk for recurrence of these cancers.

In one study, researchers found that people in northern Italy who ate seven or more
servings  of raw tomatoes every week  had a 60% lower change of developing colon, rectal,
and stomach cancer than those who only ate two servings or less.

German researchers have found that cooked tomato products containing some oil –
such as spaghetti sauce – boost lycopene absorption dramatically. They believe that
heating  and crushing releases more lycopene, and that the body  needs substances in
oil to  help better absorption.

Harvard researchers, looking at green leafy vegetables, especially spinach, had quite
an eye-opener. They found that people eating the most lutein and zeaxanthin – which
are two carotenoids , powerful antioxidants found in these vegetables – had a 43% lower risk of macular degeneration  than those eating the least.
Macular degeneration is the leading cause of irreversible vision loss in people  over 50.
Lutein and zeaxanthin concentrate in your retinas and protect them by absorbing
harmful blue-wavelength light found in sunshine.

Other members of the Phytonutrients are: flavonoids, indoles,  lignans, monoterpenes, saponins, organosulfur – and phenolic compounds, which are all powerful antioxidants,
I will discuss in future articles.  If you like to know more about plant-based nutrition,
I refer to : Nutrition studies.org