You’d be forgiven for assuming that the old adage “eat the rainbow” was just another baseless piece of advice to encourage people to consume more fruits in veggies.
But colors are extremely important when it comes to our health and whether it’s a bright red apple or an earthy green pear, the color of natural foods is a sign of the nutrients they contain.
Red apples, bell peppers and tomatoes are high in lycopene – which gives them their dark red color – and help protect against cancer and arthritis.
Blueberries, blackberries and eggplant are packed with anthocyanins, tannins and other compounds that previous research has suggested improve memory, while leafy greens and avocados are high in nitrates that studies have shown to lower the risk of heart disease.
Dr. Evangeline Mantzioris, a nutritionist at the University of South Australia, says there are at least 5,000 nutrients in different fruits and vegetables. She recommends providing a multi-colored diet to “maximize the health benefits.”
Guidelines say everyone should get at least five servings of fruits and vegetables a day, in a variety of colors to ensure the best nutritional benefits.
The Centers for Disease Control and Prevention (CDC) says that 87 percent of Americans don’t get enough fruits and vegetables in their diet every day.
RED: Protects against cancer and arthritis
Apples, strawberries, cherries and tomatoes may reduce the risk of cancer and arthritis, major studies suggest.
They are top sources of carotenoids, including astaxanthin and lycopene, which reduce the number of dangerous ‘free radicals’ in the body.
Free radicals are molecules naturally created in cells by breathing and moving, but can also be created from exposure to too much sunlight, smoking, air pollution, and industrial chemicals.
How can I get more fruits and vegetables in my diet?
Dr. Evangeline Mantzioris works as a nutritionist at the University of South Australia and has given tips on how to get more fruits and vegetables in the diet.
She says it’s important to get a “rainbow” of colors to make sure everyone is getting enough nutrients.
“Promoting a rainbow of fruits and vegetables is a simple strategy to maximize health benefits for all age groups,” she says.
Her tips are as follows:
- Shopping cart: The nutritionist suggests a rainbow of colors in your shopping cart;
- Something new: tasting new fruits and vegetables with different colors would make you eat more varieties;
- Buy differently: Vary your groceries, buy fruits and vegetables that you didn’t have last week
- Skins: She recommends eating the skins as they also contain essential nutrients
- Herbs and spices: These should be included in food whenever possible as they also have nutritional benefits
They can damage the lining of cells, proteins and DNA, increasing the risk of a whole range of diseases, including cancer and arthritis.
But antioxidants — such as lycopene — work by sucking up these molecules shortly after they’re made, reducing the risk of damage to cells.
Red fruits and vegetables are the top sources of lycopene, studies show.
A systematic review of 2020, found that the compound reduced the risk of prostate cancer by suppressing these mutations. Another review – also from 2020 — also found that it may protect against other cancers, including those of the breasts, lungs and stomach.
Red-colored foods also contain vitamin C, which can reduce inflammation levels and thus relieve arthritis symptoms.
Many small-scale studies have already linked eating strawberries to improved arthritis control.
They include one 2017 paper showing that eating 50 grams of strawberries a day for 12 weeks reduced inflammation and symptoms of osteoarthritis in participants.
ORANGE: Increases fertility
They share similar traits to their red counterparts.
But a growing body of evidence also suggests that orange fruits and vegetables increase fertility.
Carotenoids — such as beta-carotene and beta-cryptoxanthin — that give the fruits their color are antioxidants that, when consumed, are distributed in fatty tissue throughout the body, as well as the ovaries and testes.
They work by scavenging free radicals in these areas, reducing the risk of serious illness and boosting the function of the organs.
A 2018 A large study of 70,000 women found that those who ate more citrus fruits had a 22 percent lower risk of endometriosis. This is a condition in which growths form around the uterus, impairing the chance of getting pregnant.
A 2020 meta-analysis of 440,000 women also suggested a fertility benefit, concluding that those who ate more orange fruits and vegetables were significantly less likely to develop ovarian cancer than their counterparts.
Scientists also suggest that the antioxidant may protect sperm, as these cells are exposed to free radicals during their production and in the ejaculate. Little human research has been done in this area, but on a small scale 2005 study found that consumption of antioxidants, including carotene, was associated with improved sperm quality.
Orange fruits and vegetables are also important sources of vitamin C, which has been linked to improved absorption of heme iron to boost oxygen transport in the body and heart health.
Deficiencies can lead to scurvy — bleeding gums — as well as anemia and problems getting wounds to heal properly.
Orange foods include oranges, mangoes and satsumas.
BLUE AND PURPLE: Protects memory
Munching on half a cup of blue fruits — such as blueberries, blackberries and eggplant — could protect the brain from deterioration, a growing list of studies suggests.
An apple a day to keep the blues away?
Eating an apple a day could help ward off the blues, if research is to be believed.
Researchers surveyed nearly 430 adults to see how their eating habits affected their mental health.
People who ate up to the recommended five servings of fruit each day were less likely to be depressed, the results showed.
Meanwhile, the opposite was true for people who liked to eat chips. However, no such associations were found for eating vegetables.
The authors argued that the positive benefits of fruit may be due to the way people eat it raw.
Vital antioxidants, fiber and micronutrients important for brain function can be lost as part of the cooking process.
Lead author, PhD student Nicola-Jayne Tuck, from Aston University in Birmingham, said: ‘It’s possible that changing what we snack on could be a really simple and easy way to improve our mental well-being.
And many smaller studies have also pointed to the link, including one 2012 groundbreaking Harvard University study that suggested blueberry consumption slowed brain aging by two and a half years.
Scientists say that eating blue and purple fruits and vegetables boosts blood flow to key areas of the brain, ensuring a good supply of nutrients and oxygen to cells.
Anthocyanins, tannins and other antioxidants in the plants have also been linked to reducing the number of ‘free radicals’ in the body – and reducing inflammation.
YELLOW: Protects eyesight
Pineapple, corn, lemons and even bananas can all help protect the eyes from sun damage and vision loss.
They are excellent sources of lutein, zeaxanthin and other antioxidants that can occur in higher concentrations in the eye when the organ is exposed to too much sunlight.
If left unchecked, they can damage the DNA and lining of cells, which can lead to vision impairment.
But lutein and other compounds work to soak these up, preventing the worst effects.
Macular degeneration affects one in 10 American adults and tends to strike later in life, with adults gradually losing central part of their vision.
Meta-analyses of 2012 show how eating more yellow-colored fruits and vegetables significantly reduced the risk of developing this condition in participants.
Another great review of over 20 studies out 2018 concluded that ‘many studies support the beneficial effects of lutein on the eye’.
GREEN: Decreased risk of heart disease
Avocados, broccoli, Brussels sprouts, kale and other leafy greens may reduce the risk of heart disease, studies suggest — and reduce the risk of spina bifida in developing babies.
They are a top source of nitrates, which are broken down when consumed to cause the dilation of blood vessels – and a subsequent drop in blood pressure.
This reduces pressure on the heart and reduces the risk of damage to blood vessels, lowering the risk of heart disease.
A meta-analysis of 2016 found that there was a 15.8 percent lower risk of cardiovascular disease in those who regularly ate leafy greens.
Green fruits and vegetables are also an important source of vitamin K, which helps to stop calcification of large blood vessels, which increases blood pressure and leads to heart disease.
They are also sources of folic acid – the natural form of vitamin B9 – which is recommended for all pregnant women.
Numerous studies have shown that this lowers the risk of childhood spina bifida, or when a baby is born with the spinal cord protruding from the back – rather than surrounded by the spine.
BROWN AND WHITE: Antiviral and antibacterial properties
Brown and white fruits and vegetables get their color from “flavones” such as apigenin, luteolin, isoietin and others found in garlic, potatoes and cauliflower.
But they are also important sources of allicin, which studies suggest have antibacterial and antiviral properties.
At this point, however, it’s still unclear whether the compounds have the same effect in humans.
There is proof too that allicin helps lower blood pressure by causing blood vessel dilation, similar to other vegetables.