Many foods contain substances other than vitamins and minerals which are vital for health. Known as phytochemicals, these substances are antioxidants that help to protect against coronary heart disease and cancer. Take a look at the low-calorie food you should eat on a regular basis.
1. Citrus Fruits Lemons: 19kcal/100g Oranges 37kcal/100g
Citrus fruits such as oranges, lemons, limes and grapefruit are an excellent source of antioxidant bioflavonoids and vitamin C - a single fruit usually provides the recommended daily amount of 60mg per day. Oranges contain the flavonoid, hesperidin, while grapefruits contain the flavonoid naringenin. These work together with vitamin C to boost its antioxidant effectiveness, and may also have anti-cancer properties. Citrus fruits contain pectin - a soluble fibre that helps to lower a high cholesterol level. Lemons are a rich source of lemonoids and limonene - phytochemicals that protect against cancer.
Citrus fruits contain useful amounts of potassium, calcium and folate. Aim to eat at least one citrus fruit per day. Interestingly, using lime juice as a flavouring reduces the need for salt.
Several studies suggest that natural dietary intakes of betacarotene and vitamin A are important in reducing the risk of coronary heart disease and a number of cancers, including breast, lung, skin cancer (melanoma) and possibly leukaemia.
2. Broccoli 33kcals/100g
Broccoli is now recognised as one of the most beneficial green vegetables, as it contains a number of phytochemicals that help to protect against cancer. It only contains 2% carbohydrate but will boost your protein, calcium and magnesium levels. It is a good source of weak plant oestrogens such as genistein, that are converted into biologically active hormone-like substances by intestinal bacteria, especially when the diet is also rich in fibre. It also contains indole-3-carbinol, a substance needed to metabolise sex hormones in the body more efficiently. Broccoli should only be steamed or boiled briefly to help preserve these beneficial components, and can also be eaten raw in salads for optimum nutritional value. Broccoli sprouts are an exceptionally rich source of these phytochemicals and are delicious eaten raw.
3. Cherries 48kcal/100g
Cherries contain a phytochemical called ellagic acid that protects against cancer by blocking an enzyme needed for growth of cancer cell. Like black grapes, cherries contain powerful, antioxidant, red-purple pigments (anthocyanidins) with the highest quantities found in black cherries. Because of their high anthocyanidin content, eating cherries reduces the concentration of uric acid in the circulation and are said to prevent gout when half a pound are consumed daily.
Cherries also have a mild laxative action and are a good source of vitamin C and potassium.
4. Jerusalem artichokes 41kcal/100g
Jerusalem artichokes contain the enzyme, inulase, and an indigestible complex sugar, inulin, which is made up of units of the sugar, fructose. These help to stabilize blood glucose levels. As the artichoke matures, its starches are converted into digestible sugars so it becomes increasingly sweet. Immediately after being harvested it tastes bland and only provides around 7 kcals of energy. After it has been stored for a while, however, it tastes sweet and can provide up to 75 kcals.
Jerusalem artichokes are a rich source of fructo-oligosaccharides (FOS) that have a prebiotic action in the body. Prebiotics promote the growth of friendly digestive bacteria (probiotics) such as Lactobacilli, to improve digestion. These benefits can be enhanced by eating sources of healthy digestive bacteria such as live Bio yoghurt or probiotic supplements. They are also a useful source of iron, potassium, calcium, magnesium and iron.
5. Carrots 35kcal/100g
Although they are only 8% carbohydrate, carrots are an exceptionally rich source of carotenoids - the yellow-orange pigments that give carrots their vibrant colour. Carotenoids have an important antioxidant action in the body. Some carotenoids such as alphacarotene and betacarotene can also be converted to vitamin A in the body and are therefore known as pro-vitamins.
Carotenoids protect part of the retina responsible for fine vision (macula) from damage from visible blue light by absorbing these wavelengths. They can also be converted into visual purple which is needed for normal vision. The old saying that eating carrots helps you see in the dark therefore has a basis in reality.
6. Grapes 60kcal/100g
Black grapes have long been associated with good health and are traditionally given to hospital patients to help speed their recovery. Red and black grapes contain powerful, antioxidant pigments (eg anthocyanidins, resveratrol) that are believed to contribute to the beneficial cardiovascular properties of red wine plus ellagic acid, which has anti-cancer properties. They provide useful amounts of potassium and trace minerals such as boron, magnesium and copper.
7. Chillis 20kcal/100g
Eating chillies stimulates production of natural painkillers (endorphins) in the brain and mucus in the stomach, which may protect against peptic ulcers. Chillies contain antioxidants, including capsaicin, that also protect against coronary heart disease, cancer and premature ageing. Phytochemicals in chilli peppers thin the blood to reduce the risk of blood clots, high blood pressure and raised cholesterol levels. Good source of betacarotene and vitamin C.
8. Mango 57kcal/100g
Mangoes are an excellent source of carotenoids, some of which the body can convert to vitamin A. Some varieties of mango contain as much as 3g carotenoid pigments per 100g flesh. Mangoes also contain good amounts of vitamin C and fibre, plus useful amounts of potassium and vitamin E.An average mango weighs around 150g and provides around 85 kcals energy. Weight for weight, the mango flesh is 14% sugar, so provides a rapid yet healthy energy boost. Mangoes appear to have anticancer properties that are currently under further investigation.
9. Live Yoghurt low-fat, plain 56kcal/100g
Live Bio yoghurt contains cultures of digestive bacteria that line the gut and help to keep the intestines healthy. These bacteria, including Lactobacillus acidophilus, inhibit the growth of Helicobacter pylori, a bacterium linked with peptic ulcers and stomach cancer. Bio yoghurt can also reduce overgrowth of Candida albicans in the gut - a yeast responsible for recurrent thrush infections. Improves symptoms of irritable bowel syndrome such as constipation, diarrhoea and bloating. Research suggests it may boost immune function in the gut and reduce food allergy. Good source of calcium and phosphorus plus vitamins K and biotin.
10. Tea - virtually calorie-free if drunk without milk
Green, black and white teas are a rich source of antioxidants that help to protect against coronary heart disease. People drinking at least 4 cups of tea per day appear to be half as likely to have a heart attack than someone who does not drink tea. A high tea intake (eg 8 to 10 cups per day) may also reduce the risk of some cancers, especially those of the stomach and bladder. Tea is a rich source of the trace element, manganese, and is one of the few natural sources of fluoride that protects against tooth decay. Drinking tea during winter helps to boost resistance against bacterial infections.
White tea contains less caffeine than other varieties - around 15mg per cup, compared to 20mg for green tea and 40mg for black tea. Redbush tea (rooibos) is another alternative, made from the leaves of a South African shrub. It is naturally free from caffeine and research suggests it provides health benefits in the form of antioxidant, anti-inflammatory, anti-spasmodic and anti-allergy activity.