A diet rich in fruit and vegetables is your best bet for preventing virtually every chronic disease. This has been established time and again by scientific study. The evidence is so strong that it’s endorsed by UK and US government health agencies, the World Health Organisation (WHO) and virtually every major medical organisation.
It was originally thought vitamin and mineral content of fruits and vegetables, along with the all-important fibre, were the elements that conferred health benefits, but these are exciting times in fruit and vegetable research and the focus is swinging to the importance of their protective phytochemical compounds. Literally tens of thousands of these little gems are present in the plant kingdom and by unlocking their antioxidant, anti-inflammatory, anti-bacterial and immune-boosting properties, researchers are making new discoveries about their health-enhancing properties daily.
So what exactly are phytochemicals? These compounds offer protection to the plant that makes them, and when consumed in our diet offer us the same security and protection. Colour is an important aspect of these versatile phytochemical compounds because many of them are concentrated in the leaves, skin and peel. Their bright colours attract insects and birds for pollination and seed dispersal, which is vital for continuation of the plant species.
The body demands balance and variety, so the more phytochemicals in your diet, the greater the protection. While certain fruits and vegetables have benefited from more research than others, there’s no single super fruit or vegetable that will bring about super health. The body demands balance and variety.
Orange fruits and vegetables
These are rich in phytochemicals known as carotenoids. A number of studies have associated higher levels of these in the blood with a significant reduction in thickening of the arteries, which increases risk of cardiovascular disease.
Top choices: Apricots, cantaloupe melon, mango, nectarines, oranges, papaya, peaches, tangerines, butternut squash, carrots, pumpkin, sweet potatoes.
Red fruits and vegetables
Phytochemicals such as lycopene and anthocyanins maintain heart health, improve memory and urinary function and reduce the risk of cancer. Lycopene in particular has been singled out for the protection it gives against prostate cancer. Ellagic acid, which is present in many red fruits and berries such as raspberries, can bind with cancer-causing molecules, rendering them inactive.
Top choices: Red apples, blood oranges, cherries, cranberries, red grapes, pink grapefruit, red pears, pomegranate, raspberries, strawberries, watermelon, red beets, red peppers, red cabbage, radishes, red onions, red potatoes, rhubarb, tomatoes.
Yellow fruits and vegetables
These are rich in antioxidants, vitamin C, betacarotene and bioflavonoids, which reduce the risk of cancer and improve heart health, vision and immunity. Betacarotene acts as an antioxidant, neutralising damaging free radicals. Cooking increases its availability in foods.
Top choices: Lemons, yellow pears, pineapple, yellow peppers, corn, summer and winter squash, yellow tomatoes, yellow apples, turnips.
Green fruits and vegetables
Lutein and zeaxanthin are by far the most researched phytochemicals in this group. By preventing most of the blue light that enters the eye from reaching underlying structures involved in vision, they protect our eyes from light-induced oxidative damage - thought to play a role in age-related macular degeneration.
Top choices: Lettuce, watercress, courgettes, green beans, green peppers, avocado, green apples, honeydew melon, kiwi, limes, pears, artichokes, asparagus, spinach, sugar snap peas, broccoli, Brussels sprouts, cabbage, celery, cucumber, peas.
White fruits and vegetables
Allicin, which is found in the garlic and onion family, and quercetin, which is particularly abundant in apples, onions, cauliflower and cabbage, may reduce the risks of heart problems and cancer. It might also help maintain a healthy level of blood cholesterol and help control blood pressure. Quercetin inhibits the release of histamine, which causes congestion, and studies have shown improved lung function and lower risk of certain respiratory diseases in people with a high intake.
Top choices: Bananas, dates, white peaches, cauliflower, chives, fennel, garlic, ginger, spring onions, Jerusalem artichokes, leeks, mushrooms, onions, parsnip, potatoes, shallots.
Blue, Indigo and violet fruits and vegetables
These are best known for being very rich in flavonoids, which protect plants from damage and perform the same function in humans. Food with a blue, purple or violet colour has a high phenolic content and can block specific enzymes that cause inflammation. Resveratrol, found in abundance in red grapes, has received a great deal of attention in connection with the so-called French Paradox. In essence, it appears that although the French eat a diet that’s relatively high in saturated fat, they show greatly reduced rates of coronary heart disease because of their regular consumption of red wine with their food.
Top choices: Blackberries, blueberries, blackcurrants, figs, purple grapes, plums, prunes, raisins, purple broccoli, aubergine.
Fiona Kirk is a nutritionist and author of ‘So What The F*** Should I Eat?’ and ‘2 Weeks in the Fast Lane’. To purchase her books at the special reader offer price and sign up for her newsletter, visit fionakirk.com and quote the following at checkout:
Ref: BNSW for ‘So What The F*** Should I Eat?’ (£10 plus p+p)
Ref: BN2W for ‘2 Weeks in the Fast Lane’ (£5 plus p+p)
For more expert diet and nutrition advice, get the magazine. Subscribe now and get five issues for £5.
Ways to ensure you’re getting enough phytochemicals
- Make sure your shopping basket is full of colour
- Juice a couple of fruits every day
- Steam a small bag of mixed vegetables, drizzle with olive oil and lemon juice and eat while you’re preparing your evening meal
- Fill at least half your lunch/dinner plate with salad or vegetables
- Keep fruit and raw vegetables in your briefcase or desk drawer to snack on
- Keep a fruit bowl where you can see it and refill it regularly
- Experiment with cooking methods for both fruits and vegetables – steam, grill, bake, roast, puree (the internet is bursting with suggestions)
