Avocados can also act as a prebiotic, a type of fibre that acts as a food for the gut microbiome. One clinical study found a study group who ate avocados daily had greater gut microbe diversity than a control group who didnβt.
βBoth are good sources of vitamin C which can help with absorption of iron from non-meat sources such as green vegetables and legumes. And theyβre great to add as a marinade,β says Hobson.
Avocados are a rich source of healthy monounsaturated fats.Credit: iStock
βLemons also contain a soluble fibre called pectin which can help to reduce levels of βbadβ LDL cholesterol.β
βLemons and limes also contain calcium for strong bones and potassium to help control blood pressure,β says Gill. βCitrus peel contains plant chemicals called polymethoxylated flavones (PMF), a type of plant chemical called flavonoids, which may be protective for brain health and can be used as zesty seasoning in savoury dishes to add a tartness, or you can infuse water with it or add to sweet desserts.β
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Raspberries not only contain vitamin C β vital for a healthy immune system, wound healing, healthy skin and blood vessels β but also antioxidant compounds called quercetin, and a potent antioxidant, ellagic acid, which some studies suggest may prevent or slow down the progression of chronic diseases.
Anthocyanins, a pigment found in red and purple fruit, have βanti-diabetic, anti-cancer, anti-inflammatory, anti-microbial and anti-obesity effects, as well as prevention of cardiovascular diseaseβ, says Gill.
βSome studies β in animals and the laboratory β have suggested they may be potentially useful for reducing the risk of metabolically based chronic disease, particularly cardiovascular disease, type 2 diabetes and Alzheimerβs.β
Raspberries also provide one of the highest amounts of dietary fibre per 100 grams in all edible plant foods.
Blackberries have been the subject of extensive research due to their high antioxidant content. They contain chemicals that can prevent the cell damage that can result in diseases such as heart disease and cancer.
βThe dark purple colour of blackberries comes from anthocyanins, which have been linked to reducing the risk of chronic disease such as heart diseases and neurodegenerative diseases,β says Hobson.
Other health benefits reported for blackberries include reducing cholesterol, delaying the ageing process, relieving pain and strengthening blood circulation.
Raspberries are low in calories but high in fibre, vitamins, minerals and antioxidants. Theyβre also delicious. Blackberries have been the subject of extensive research due to their high antioxidant content. Credit: iStock
Grapefruits are high in vitamin C. Half a medium grapefruit contains half a dayβs recommended intake needed for a healthy immune system, as well as high levels of vitamin A (beta-carotene) important for eye health.
βRed grapefruits are also rich in an antioxidant called lycopene, which is good for menβs prostate health and has been linked to lower stroke risk,β says Hobson.
Although grapefruits are low in calories, they donβt have any magical weight-loss properties, as popular myth would have it.
A downside of grapefruit is that it blocks an enzyme that can help your body break down certain medications for blood pressure, allergies and for lowering cholesterol, so always read the patient information leaflet to check for a warning about this.
Strawberries are not just for summer. Researchers found a 2.5-gram serving a day of freeze-dried strawberries improved cardiometabolic health, including insulin levels (and insulin resistance), and blood fats in overweight adults with high LDL cholesterol levels. βStrawberries may well be useful for people with type 2 diabetes, but more research is needed,β says Gill.
One study found anthocyanins in strawberries and other red/purple fruits may help reduce heart attack risk by lowering blood pressure.
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βTheir high vitamin C content also makes strawberries important for collagen production, the scaffolding structure in the skin, as well as healthy cartilage in the joints,β adds Hobson.
βHoneydew melon is 90 per cent water so good for hydration,β says Gill.
βThe gut needs adequate fluids to function properly and maintain digestive processes. Maintaining hydration keeps things moving by facilitating the travel of food at the right consistency along the gut. It can also help to prevent constipation, and also with food breakdown so your gut can absorb nutrients.β
Honeydew melon also contains potassium which is linked to maintaining a healthy blood pressure and contains vitamin K, folate and magnesium needed for bone health.
βThe orange colour in peaches is due to a group of compounds called carotenoids which act as antioxidants in the body,β says Hobson.
βCarotenoids such as beta-carotene are converted to vitamin A in the body, which plays a key role in the immune system. This includes maintaining the mucous membrane barriers on the eyes and in the gut, which help to trap bacteria and other pathogens.
The orange colour in peaches is due to a group of compounds called carotenoids.Credit: Bloomberg
βEmerging research in lab and animal studies show that peaches may also protect the skin and prevent UV damage,β says Gill.
Oranges have exceptionally high vitamin C content, which increases protection against infections and has an antioxidant effect. You would have to eat 15 apples to get the same amount of vitamin C found in one orange.
βSome research has suggested oranges may also have anti-inflammatory properties which may be beneficial in chronic diseases,β says Gill.
βDrinking orange juice with a meal can also boost absorption of iron from meat and plant sources.β
βKiwi fruits are rich in vitamin C and a dietary source of melatonin, the sleep hormone that helps regulate circadian [body clock] rhythms, so may help improve sleep,β says Hobson. βOne study (in elite athletes) found that eating two kiwis two hours before bed had a positive effect on sleep.β
Kiwi fruits are also well known as an effective treatment for constipation, which affects 10 to 15 per cent of people globally. βItβs thought that they help gut motility by increasing water retention in the small intestine, and decreasing transit time, which can improve stool consistency and frequency, as well as other gut symptoms such as pain and discomfort,β says Gill.
The Telegraph, London
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