Can a fruit juice cure YOUR health problems as scientists discover beetroot juice can protect against dementia?

Updated: 03:11 EST, 5 November 2010

Pomegranate for prostate cancer, cranberry for urinary infections: The ultimate good juice guide

We all know that fruit juice is generally good for you. But every day it seems scientists are discovering new benefits for specific illnesses.

Yesterday, U.S. researchers revealed that beetroot juice can help keep dementia at bay, as it contains nitrate, which helps open blood vessels, boosting blood supply to the brain.

So, what ailments can other popular juices help to treat? Here, PETA BEE presents the ultimate good juice guide.

But a word of warning: while a couple of glasses can be good for you, too much can be bad for your teeth - and waistline...

POMEGRANATE JUICE FOR PROSTATE CANCER

How it works: Pomegranate contains a cocktail of chemicals which appear to reduce cell damage and potentially kill off cancer cells, according to scientists at the University of ­California.

They asked 50 men with prostate cancer to have a glass (0.24 litres) of the juice daily. They then kept track of the men’s levels of prostate specific antigen (PSA), a protein linked to prostate cancer.

Usually cancer patients’ levels double in about 15 months, but in patients who drank pomegranate juice it took an average of 54 months for their PSA levels to rise.

Also good for: Fighting heart disease and lowering ‘bad’ LDL cholesterol — antioxidants in pomegranate juice may help reduce the formation of fatty deposits on artery walls. (Antioxidants are compounds which help to destroy free radicals, harmful molecules produced by the body and environment and which are linked to a range of diseases, including cancer.)

It is always best to have fresh juice where ­possible, but if not, go for pasteurised over ­concentrates which can be packed with sugar.

Recommended brand: Rubican Pomegranate Juice Drink, £1.49 per litre from good supermarkets

GRAPEFRUIT JUICEFOR WEIGHT LOSS

How it works: By aiding more efficient metabolism of sugars, it can be a useful aid to weight-loss programmes. A U.S. study looked at the benefits of grapefruit by dividing 100 obese people into three groups: one group was given half a grapefruit before each meal, another had a glass of grapefruit juice, while the remaining third had no grapefruit.

After 12 weeks, those eating grapefruit had lost an average of 3.6lb and those drinking grapefruit juice lost an average of 3.3lb. But those in the control group who consumed no grapefruit lost only an average of 0.5lb.

Also good for: Enhances the body’s absorption of coQ10, an energy compound vital to our cells. Boosts the anti-cancer effect of certain drugs (but can adversely interfere with other medication, so check with your doctor first).

Recommended Brand: Prince Grapefruit Juice, £1.39 for 1 Litre, and Tropicana 100pc Squeezed Grapefruit Juice, £1.94 for 1 litre from good supermarkets.

CRANBERRY JUICE FOR URINARY INFECTIONS

How it works: A study conducted this year showed that cranberry juice prevents the growth of the bacteria E.Coli, the most common cause of urinary infections.

Researchers who presented their findings to the American Chemical Society showed that within eight hours of drinking a glass of cranberry juice, the juice could help prevent bacteria from developing into an infection in the urinary tract.

However, contrary to popular belief, the juice will not treat cystitis if the infection has already occurred ­— indeed, because it is acidic it can actually exacerbate the discomfort.

Also good for: Raising the levels of ‘good’ HDL cholesterol through high levels of polyphenols, the antioxidants in the fruit; reducing the risk of gum disease and stomach ulcers (because of anti-bacterial benefits).

Recommended Brand: Ocean Spray Cranberry Classic Juice Drink, £1.17per litre from good supermarkets.

APPLE JUICE FOR ALZHEIMER’S

How it works: Drinking apple juice maintains your levels of a brain chemical called acetylcholine, which is vital for memory and brain health (low levels are linked to Alzheimer’s Disease), according to a U.S. study. 

Although the research was conducted on mice, researchers suggest that two glasses (500ml in total) of apple juice a day could have similar benefits in adults,

Also good for: Aids digestion and healthy bowel function thanks to its high fibre content. Might also help to lower cholesterol.

Recommended Brand: Copella Apple Juice, £1.08 for 330ml from Tesco and other supermarkets.

CHERRY JUICE FOR CRAMP AND GOUT

How it works: Recent studies at Northumbria University have shown that runners who drank the juice of Montmorency cherries — a tart-tasting fruit that is particularly rich in antioxidants — twice a day for five days before the London Marathon recovered much more quickly and experienced less muscle pain than those who didn’t.

In addition, cherry juice can help ease the agony of gout by helping the body to excrete the uric acid linked to the painful joint condition.

Also good for: Drinking a glass of cherry juice a day offers the same health benefits as eating 23 portions of fruit and vegetables, one study found. A 250ml serving of the juice contained more antioxidants than five portions of peas, tomatoes, watermelon, carrots and banana.

Recommended Brand: CherryActive concentrated juice (add water) £14.49 for 473ml from Holland & Barrett, and Vimto Cherry Juice, £1.20 for 725ml from Tesco.

ORANGE JUICE FOR HEART DISEASE

How it works: Orange juice contains an antioxidant called hesperidin, which improves blood vessel function, helping to cut your risk of heart disease.

U.S. researchers found that men who drank 500ml of orange juice (containing 292mg of hesperidin) daily had lower blood pressure than those who took an antioxidant supplement.

Also good for: Preventing kidney stones. It is known that supplements of citrate, a substance found in citrus juices, can help slow the formation of kidney stones, but some people find the acidic nature of the pills hard to tolerate. A daily glass of orange juice produces similar benefits.

Recommended Brand: Tropicana — their Smooth Orange Juice is £1.96 for 1 litre from all good supermarkets.

PINEAPPLE JUICE FOR ARTHRITIS

How it works: The enzyme bromelain, found in the flesh and juice of pineapples, helps the body digest proteins and aids digestion, but also has other major benefits. 

When taken on an empty stomach, bromelain acts as an anti-inflammatory agent which has been shown to reduce arthritis joint pain and swelling. One study showed a combination of enzymes including bromelain may be a safe alternative to anti-inflammatory drugs for people with osteoarthritis of the knee.

Also good for: Helps ease symptoms of coughs and colds and thins the blood, although doctors are not yet clear why.

Recommended Brand: Del Monte Pure Gold Pineapple Juice, £1 for 1 litre from Tesco.

ACAI BERRY JUICE FOR CANCER

How it works: Acai juice, which is made from a berry found in South America, has been shown to have very high levels of antioxidants with even more than cranberry, raspberry, blackberry, strawberry or blueberry. Studies by the University of Texas have found that drinking the juice daily can help prevent the development and spread of cancer cells.

Also good for: Aiding weight loss — it stabilises blood sugar levels, so preventing appetite swings.

Recommended Brand: The Berry Company Acai Juice, £1.75 for 330ml from Holland & Barrett.

PURPLE GRAPE JUICE FOR MEMORY LOSS

How it works: A study by psychiatrists at the University of Cincinatti found that a daily drink of the juice improved patients’ memory significantly compared with a placebo. Experts think the grapes provide brain-boosting antioxidants.

Also good for: Lowers cholesterol and can be as effective as a daily aspirin in helping to prevent blood clots. The fruit contains higher levels of disease-fighting antioxidant compounds than red wine and apple juice according to the U.S. Department of Agriculture.

Recommended Brand: Welch’s Purple Grape Juice, £1.80 for 1 litre from supermarkets.

COCONUT WATER FOR EXHAUSTION

How it works: Madonna and Gwyneth Paltrow are among those who drink coconut water (taken from the centre of the fruit; coconut milk is made with the flesh) to speed up recovery after workouts. 

Enthusiasts have dubbed it ‘nature’s sports drink’ because it contains everything you need — fluid for rehydration, carbohydrates for energy and electrolytes (or body salts) to replace what’s lost through sweat, but with only 46 calories per serving, and no fat.

Also good for: Offsetting hunger pangs by stabilising blood sugar, lowering cholesterol and blood pressure thanks to its antioxidants.

Recommended Brand: VitaCoco 100pc Pure Coconut Water, £1.75 for 330ml from Holland & Barrett.

CARROT JUICE FOR COLORECTAL CANCER

How it works: Researchers at Newcastle University isolated a compound in carrots that has been shown to fight cancer and found that rats fed either the compound, called falcarinol, or raw carrot juice in addition to their normal food had a one-third lower risk of developing colorectal cancer than rats not given the compound.

Falcarinol is a natural pesticide found in carrots that protects the vegetable against fungal diseases — in the human diet, carrots are its only source.

Also good for: Enhancing immunity (thanks to high levels of vitamin C), maintaining (but not improving) quality of vision (rich in vitamin A), aiding digestion (good source of fibre).

Recommended Brand: Eden Organic Carrot Juice, £1.97 for 750ml, Tesco.

TOMATO JUICE FOR SUNBURN

How it works: Researchers have shown that lycopene, the substance that makes tomatoes red, is a great antioxident.

It has been scientifically proven to help protect skin from sun damage, perhaps by neutralising the harmful effects of UV light. In tests, people who ate more tomatoes had 33 per cent more ­protection from sunburn.

Also good for: Several studies have shown that a regular consumption of tomatoes — particularly processed, juiced or cooked — is linked to reduced risk of prostate cancer. 

Evidence is inconclusive, but Cancer Research UK says: ‘Many doctors believe the current evidence is promising enough to encourage men to eat more tomatoes.’

Recommended Brand: Popular brands include Dawtona Tomato Juice, 66p for 330ml.

BLUEBERRY JUICE FOR DEMENTIA

How it works: Substances in blueberries may help keep the brain healthy, suggested a small study at the University of Cincinatti earlier this year.

Researchers looked at the effect of blueberry juice on memory in adults in their 70s who had age-related memory decline. Those who drank a pint of blueberry juice daily for 12 weeks performed significantly better in memory tests.

Also good for: Stabilising blood sugar levels, preventing food cravings that can lead to weight gain.

Recommended Brand: Pomegreat Blueberry Juice Drink, 99p for 1 litre from most supermarkets.