Installing wth colour

Carotenoids are organic pigments that are naturally occurring in the chloroplasts and chromoplasts of plants and some other photosynthetic organisms like algae, some types of fungus and some bacteria.
There are over 600 known carotenoids; they are split into two classes, xanthophylls (which contain oxygen) and carotenes (which are purely hydrocarbons, and contain no oxygen). Carotenoids in general absorb blue light.
They serve two key roles in plants and algae: they absorb light energy for use in photosynthesis, and they protect chlorophyll from photodamage.
In humans, four carotenoids (beta-carotene, alpha-carotene, gamma-carotene, and beta-cryptoxanthin) have vitamin A activity (meaning they can be converted to retinal), and these and other carotenoids can also act as antioxidants.
People consuming diets rich in carotenoids from natural foods, such as fruits and vegetables, are healthier and have lower mortality from a number of chronic illnesses
However, a recent meta-analysis of 68 reliable antioxidant supplementation experiments involving a total of 232,606 individuals concluded that consuming additional β-carotene from supplements is unlikely to be beneficial and may actually be harmful,
Although this conclusion may be due to the inclusion of studies involving smokers
With the notable exception of Vietnam Gac and crude palm oil, most carotenoid-rich fruits and vegetables are low in lipids. Since dietary lipids have been hypothesized to be an important factor for carotenoid bioavailability, a 2005 study investigated whether addition of avocado fruit or oil, as lipid sources, would enhance carotenoid absorption in humans. The study found that the addition of both avocado fruit and oil significantly enhanced the subjects' absorption of all carotenoids tested (α-carotene, β-carotene, lycopene, and lutein).