Nutritionists view grapes as nature's gift to all, especially to people who don't want to be old before their time. They supply energy, vitamins, minerals in addition to many other benefits.
Red grapes in particular contain resveratrol, a chemical that inhibits oxidization, thereby preventing cancer and slowing the aging process, say Dr. Pho Thuan Huong and pharmacist Tran Xuan Thuyet.
Other important compounds in grapes include the flavonoids, which are natural antioxidants that help ward off cancer as well as atherosclerosis.
In the latter case, the effect is to reduce blood pressure and thus lower the risk of coronary and cerebral blood vessel catastrophe.
Then there's linoleic acid, an unsaturated fatty acid that can raise the level of the good cholesterol HDL (high-density lipoprotein) and decrease that of the bad cholesterol LDL (low-density lipoprotein), another plus for the circulatory system and the body as a whole.
Intake of the oil of grape seeds every day reduces the risk of cardiovascular disease by 39 to 56 percent, according to Dr. Huong.
American researchers have determined that, while men with a low HDL count can easily become impotent, the deterioration can be reversed over a long period of time with a daily intake of grape seed oil to raise the HDL count.
With a water content of 75-85 percent and just 70 calories per 100g of ripe fruit, grapes make the perfect stomach filler for the weight conscious.
The rest, mainly in the skin and seeds, is pure goodness in the form of glucose, fructose, phlobaphene, potassium, magnesium, calcium, iron, enzymes, vitamins B1, B2, B6, B12, A, C, P, K and PP, and gallic, silicic, phosphoric, lemon, oxalic, folic and other essential acids.
Research at Poland's Nutrition and Food Institute has revealed that the mineral and vitamin content of grapes is five times that of apples, plums, mangos and oranges.
All in all, fresh grapes are an ideal tonic for convalescents, pregnant and postnatal women, and anyone else who needs a physical pick-me-up.
Pharmacist Thuyet says that, besides lowering the risk of stroke, grape juice fortifies the stressed or fatigued body, revives the strength of cancer sufferers whose disease is in remission, overcomes indigestion and eases constipation.
Thuyet warns, however, that the juice of red grapes can have an adverse effect on the effect of blood-pressure medicine, particularly calcium channel blockers like amlodipine, nifedipine, diltiazem, verapamil and nicardipine.
In addition, red grape juice raises the level of potassium in the blood when taken in conjunction with benazepril, captopril, cilazapril, enalapril and other angiotensin-converting enzyme inhibitors.
Washing grapes the right way
Start off with a pair of sharp scissors and cut off the top peduncle, which is close to the grape, to separate the fruit without tearing the skin. Discard any spoiled grapes, place the good ones in a basin, and wash off the grit and dust. Then soak them in salty water for 30 minutes, rinse again, place in a colander, rinse under a strong stream of cool tap water, and leave to drain.
Once the grapes are dry, pour warm water in a bowl, put the grapes in the bowl, then take them out and put in a clean basket. Now the grapes are ready to be eaten pips and all, or blended whole for their juice.
Regular drinkers of alcohol should stick to wine for their beneficial grapes, advises Dr. Luong Le Hoang, while people who work in contaminated environments should drink plenty of straight grape juice.
As mentioned above, the flavonoid compounds found in grapes and their leaves are known to be better oxidants than vitamins C and E. And thanks to their extra potassium, grapes can be used to lower blood pressure and thereby prevent a coronary or other such disaster.
Researchers at Wisconsin University in the US say that grape eaters are less at risk of a cerebral blood vessel catastrophe because certain chemicals in grapes keep blood thin by hindering build-up on the walls of blood vessels.
Similarly, studies conducted in France prove that potassium works to improve blood circulation and harmonize blood pressure.
Stimulating intelligence the natural way
The folic, gallic, silicic and phosphoric acids and other important compounds found in grapes seem to benefit the central nervous system too. In a sense, they are a form of "natural doping."
Dr. Huong says the B-group vitamins like thiamine and niacin found in fresh grapes help improve intelligence and memory. Whatever the mechanism is, they are good medicine for hot tempers and anxiety too.
These B-group vitamins also work to improve digestion, prevent constipation, and stimulate the kidneys, allowing the body to metabolize and excrete toxins quickly and thoroughly.
Eating fresh grapes can ameliorate fatigue and headaches, improve liver function, fight inflammation and prevent gall stones. Grapes are good for menopausal women too as they balance estrogen levels and thus prevent that softening of the bones called osteomalacia.
Interaction of grapes and medication
According to Dr. Huong, grape juice is linked to a group of enzymes, collectively called Cytocrome P450, that can inhibit the metabolism of certain drugs by the liver. Some examples:
- The end result of eating grapes can slow the liver's breakdown of diltiazem, verapamil and the other calcium channel blockers. So people taking medicine for hypertension should avoid grapes in the main, and only drink a little grape juice if any. Otherwise the unmetabolized drugs can build up in the system and affect the body accordingly.
- The antihypertensive agents' benazepril and captopril react with potassium, of which grapes contain a lot. So anyone taking either of these medicines should be sparing when it comes to eating grapes.
- Red grape juice enhances the effect of cyclosporine, an immunosuppressant given after an organ transplant, for example the cornea or liver. This means that a donor recipient can eat grapes to lower the dose of cyclosporine, and thus the price of treatment, and reduce the drug's side effects as an added benefit.
With a heart transplant, an organ recipient who eats grapes needs only half the normal dose of cyclosporine and ketoconazole.
- In addition, grapes augment the effect of caffeine, theophylline, estrogen mydazolam and terfenadine.
- Recent research in the US found that the polyphenol antioxidant in grape seeds can help prevent or at least delay the onset of Alzheimer's disease.
- Whole red grapes can be thrown in the blender to make a delicious juice.
- To make a face mask, mix yogurt with egg yolk and crushed whole red grapes, and apply to the facial skin for 20 minutes before going to bed at night.
Or simply crush some whole red grapes, cover the face with the juicy pulp for 15 minutes, and rinse off with tonic water. To keep the skin smooth, use this second method once in the morning and again in the evening for 25 days.
- Drinking red wine can lower the risk of death from a cardiovascular event by 40 percent. What's more, people who drink 60ml of red wine every day are 30 percent less at risk of developing cardiac disease compared to teetotalers.