Eat The Rainbow

What is eating the Rainbow? My family, friends and clients are frequently subjected to hearing me bang on about ‘eating the rainbow’, but what do I actually mean. It’s simple really, eating a wide variety of different coloured plant foods, such as fruit, vegetables, herbs and legumes.

Why Is It So Important

I am sometimes asked why I’m so obsessed with this. Well while many of us are aware the importance of eating fruit and vegetables to provide a rich source of vitamins, minerals and fibre, these foods are also the primary source of bioactive compounds known as phytonutrients (phyto from the Greek for plants).

Over 5000 of these bioactive compounds have been identified, and many now have a substantial body of evidence supporting their health benefits (1) Phytonutrients provide us with and are utilised by our bodies for their antioxidant, anti-inflammatory, antibacterial, antifungal, antiallergic, chemoprotective, neuroprotective and blood pressure lowering functions and properties (2).

We also know that eating a wide variety of different plant foods has been associated with a lower risk of a range of chronic illnesses such as diabetes, cardiovascular disease and some cancers, as well as improved cognitive function (potentially reducing risk of Alzheimer's) (3-5).

But despite their incredible health benefits, here in the UK less than half of the population are meeting the “5 A Day” fruit and vegetables guidelines which is very likely to be leading to a phytonutrient gap and playing a role in increased incidences of many diseases.

Why are different colours so important

Phytonutrients are responsible for giving fruit and vegetables their vibrant colours, different phytonutrients have different colour pigments. So different coloured plant foods, contain different phytonutrients, which in turn means different health benefits! The more variety of different coloured plant foods, the broader the spectrum of phytonutrients we will consume and broader  the protection our diet will give us.

So bearing all this in mind lets take a little look a some of the various phytonutrient colours and the benefits they provide

Yellow/ Orange

These fruits and vegetables contain a family of powerful antioxidant known as carotenoids. There are a number of different carotenoids but Alpha and Beta carotene are often the most prevalent. Vegetables such as sweet potato and carrots have displayed a vital role in reducing inflammatory responses and oxidative stress. This indicates they may offer protection against several chronic diseases including many cancers, osteoporosis, heart disease and cognitive decline associatedwith ageing and Alzheimer's. 

Other great sources of beta-carotene include, squash, apricots, cantaloupe melon, peppers and even broccoli (I know not technically orange!). Since beta-carotene is a fat soluble compound it is more easily absorbed in the presence of fat, try drizzling a little olive oil over your veggies or have along side a serving of oily fish such as salmon, mackerel, sea bass.

Red

Tomatoes, raw, cooked, even tinned and sundried are a rich source of lycopene, another antioxidant in the carotenoid family. Lycopene has been shown to be protective to cardiovascular health and brain health, support healthy blood pressure and reduce inflammation (6). Lycopene also offers protection from the damaging effects of the sun (7) and has been shown to protect against a number of different cancers (8-9).

Other great sources of lycopene include watermelon, apricots, pomegranate and pink grapefruit.

Red apples are a rich source of the flavanol quercetin, which is known for its ability to reduce inflammation, fight free radical damage, reduce the risk of cancer, heart disease, neurological diseases (such as alzhimer disease), lowering blood pressure and relieving allergies.

Other foods rich in quercitin include broccoli, cabbage, cauliflower, onions, peppers, grapes, berries, red peppers, nuts and seeds.

Other nutritious red foods to include in your rainbow diet could be red kidney beans, red lentils, raspberries, cherries, grapes, red onions, red peppers

Purple/ Blue

Sometimes referred to as a ‘superfood’, beetroot is rich in several beneficial phytonutrients. It’s rich purple colour is due to a family of compound, betacyanins. Betanin has strong antioxidant properties which can protect the cell membranes of neurons against oxidative damage (10). Betaine has a positive influence on the bile ducts, to improve digestion and toxins can be excreted from the body more efficiently. It also helps our body to lower homocysteine levels protecting against heart attacks, strokes, Alzheimer’s and Parkinson’s.

Blueberries are a nutritional powerhouses, rich in anthocyanins, part of a family of polyphenol antioxidants called flavonoids, which have been shown to be protective against cardiovascular disease, high blood pressure and type 2 diabetes. Owing to their ability to protect neurons against oxidative damage and suppress neuro-inflammation, anthocyanins have also been proposed as a therapeutic strategy against neurodegenerative diseases (11).

Other great sources of anthocyanins include blackberries, elderberries, chokeberries, red cabbage, purple carrots, aubergine and purple grapes (11).

Green

Cruciferous vegetables offer a rich source of glucosinolates. These sulphur containing compounds give these foods their unique aromas and slight bitter taste. They are broken down by the body into several different active substances with wide-reaching health benefits. One example is sulforaphane, which has exhibited numerous health benefits such as supporting healthy blood glucose and cholesterol levels, reducing neuro-inflammation, thereby supporting cognitive health, musculoskeletal health and exhibiting protection against numerous types of cancer (12). 

The phytochemical compounds in cruciferous vegetable are supportive of liver function, helping eliminate waste and toxins and are particularly useful for eliminating used hormones to support healthy hormone balance. 

Cruciferous vegetables include broccoli, cauliflower, kale, brussels sprouts, rocket, bok choy, watercress and mustard greens. We should try to include at least one portion of these vegetable daily. Try roasting cauliflower with a sprinkle of rosemary or sumac and a little olive oil. I love brussels sprouts just steamed, but try them roasted with a little nutmeg and served with basil pesto, delicious! 

Spinach is a rich source of the carotenoid lutein, which is concentrated in the human eye, where it protects against oxidative damage, filters blue light, to protect photoreceptor cells from damage and reduces inflammation (13). Lutein has demonstrated protection against eye diseases such as cataracts and age-related macular degeneration, as well as exhibiting health benefits to other areas such as cognitive function and cardiovascular health (13-14).

Other great sources include kale, chard, broccoli, peas, lettuce, basil, parsley 

Brown/ White

Onions are member of the allium family and are among one of the oldest of all cultivated plants. They have been used medicinally for thousands of years and provide a wide range of flavanols, at least 52 have been identified! Flavonols can modulate the effects of oxidative stress and inflammation (15). Onions are particularly rich in the flavanol quercetin, which can support healthy blood pressure (16), has strong anti-inflammatory, immune supportive, anti-carcinogenic, anti-diabetic, and anti-viral properties (17-18).

Other great members of the allium family include garlic, chives, shallots and leeks.

Lets Eat The Rainbow

The latest information suggests that only 27% of adults (19-24years) get the recommended ‘5 a day' and a mere 8% of children (11-18years). However research scientist believe that 7.8 million premature deaths could be prevented world wide if we ate 10 portions! 

TEN PORTIONS, I hear you say, how on earth can we do that. Including fruit or vegetables at every single meal, yes breakfast too, and eating them for snacks is a great start. 

Breakfast is often a rushed (or non existent) affair for many. If this is you then consider making a smoothie. Prepare the fruit and veg (yes I did say veg) the night before, add in some nuts, seeds, oats for extra protein and fibre and store it in the blender cup in the fridge, ready to be whizzed up in the morning. Or prepare some 'Overnight Oats', simply place oats in a glass jar, sprinkle over some cinnamon, stir through some seeds (sunflower, pumpkin, chia), cover with milk of your choice, seal with a lid and pop in the fridge overnight. In the morning top with mixed berries and or poached plums, apples or pears.

If you've more time consider an omlette or simple fried egg with mushrooms, tomatoes and spinach (I cook this all together in the pan with the egg) serve with some smashed avocado and rocket.

When the hunger pangs strike, instead of reaching for that bag of crisps or chocolate bar mid morning or afternoon, have some berries (add a dollop of yogurt), sliced apple with nut butter, or prepare some raw veg sticks (carrot, pepper, broccoli) and dip into some hummus.

Cooking as much as possible from scratch, means you can add more veggies into casseroles, lasagne, chilli etc. Get creative with your vegetables, don’t see them as just a side dish on your plate. Treat them as the main event. Most vegetables can be roasted, drizzle with a little olive oil and sprinkle with herbs and spices. Mix different types of veggies and throw them all in a large oven dish, by varying the size you cut different vegetables means you can cook different varieties all together for the same amount of time.

A favourite of mine is Brussels sprouts roasted with a little olive oil, sprinkled with a little nutmeg, black pepper and a generous amount of sage (fresh or dried). After roasting (about 15 mins) top with some pesto, hummus and mixed seeds, I love this for lunch with a green salad, tomatoes and feta.

Another great idea, and a tasty step up form just boiling vegetables is to steam/fry with a little stock, herbs and black pepper. Makes a great accompaniment, to meat and fish or elevate to a main meal lunch with some extras such as pouring over a simple tahini sauce (whisk 100ml of tahini, 100ml of water, 60ml lemon juice, 2 cloves of garlic, pinch of salt and 20g of chopped parsley) dolloping on some pesto, hummus or greek yoghurt mixed with a little olive oil, dried mint and black pepper, crumbling over some fets, then sprinkle with seeds (pumpkin, sunflower, hemp).

Growing some fresh herbs can make such a tasty difference too. You don’t need much space, a windowsill will do.

Varying the variety of fruit and veg will ensure we get as many different colours and therfore as many different phyto-nutrients as possible. Try to eat 20-30 different types of fruit, vegetables, herbs and spices over the course of 2-3 weeks, rather than having the same things over and over. These foods are't just good for our us, they also provide fuel for our microbiome, but thats something for me to write about another day!  

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