“How much prune juice should I drink?” is a frequently asked question on the Total Health. In addition to the article by Dr Premchand here is a useful summary of some relevant studies into the health benefits of prunes that have been published in the medical literature.
- What are prunes and prune juice?
- What is constipation?
- How does prune juice improve digestive health and deal with mild digestive problems?
- Should I consult my doctor before regularly drinking prune juice?
- How much prune juice should I drink if I have mild digestive problems like constipation?
- How much fibre do prunes contain?
- What else do prunes contain?
- Is there evidence that prunes promote bone health?
- How long does it take for prune juice to work?
- What does prune juice taste like?
- If my digestive health is okay should/can I still drink prune juice; how much should I drink and how often?
- Is it possible to drink too much prune juice?
- Where can I get advice on planning a healthy diet and exercise?
Prunes come from plums, which have been cultivated and propagated possibly for thousands of years. They are the partially dried fruit of any one of the various varieties of plum cultivars. The plums are dehydrated in hot air at 85 to 90 degrees Celsius for 18 hours, and they can then be further processed into prune juice, puree, or other prune products. If there was ever a ‘king (or queen) of health foods’ it would appear that the humble prune would wear the crown as they are highly nutritious and provide considerable health benefits.However, although our knowledge is growing, little is really understood of how their range of nutrients and natural plant chemicals (phytochemicals) actually work at the biological level.
Constipation is a digestive disorder that affects the bowels either by reducing the frequency of bowel openings or difficulty is the passage of motions. It can cause bloating, abdominal pain and hard stools.
Anecdotal evidence that plums, prunes and prune juice can encourage the digestive system to work goes back hundreds of years, but recent clinical and chemical studies suggest that it is the combination of fibre and the presence of sorbitol. Sorbitol is similar to glucose, but unlike glucose, it is very slowly absorbed into the blood. As a consequence of this slow absorption as it passes through the gut, the sorbitol tends to hold onto some water. This then increases the moisture content of the stools which leads to easier passage from the body.
If you are receiving medication for a condition relating to you digestion or under regular medical care for a pre-existing condition and you have a digestive health issue then do mention it to your GP, consultant or nurse.
The recommended daily amount is 120ml, but if you have digestive health issues you may want to drink more or less than this. In most situations self- adjusting the intake is appropriate although you may also ask your doctor or health professional if you are under their care.
According to a study carried out by Stacewicz-Sapuntzakis et al from the Department of Human Nutrition and Dietetics, University of Illinois at Chicago, which summarised the current knowledge of the chemical composition of prunes and their biological effects on human health, although prune juice contains no fibre (as it is a filtered product), the laxative action of both prune and prune juice could be explained by their high sorbitol content (14.7 and 6.1 g/100 g, respectively). Sorbitol is a bulk sweetener that occurs naturally in a wide variety of fruits and berries.
Dried prunes contain approximately 6.1g of dietary fibre per 100g, although prune juice is devoid of fibre as it is filtered before bottling.
Prunes are good source of energy in the form of simple sugars, but they do not give rise to a rapid rise in blood sugar concentration, possibly due to their high fibre, fructose, and sorbitol content.
Prunes contain large amounts of unique phytonutrients (essential nutrients that come from plants) called neochlorogenic and chlorogenic acids. These substances are classified as phenols, which are chemicals found in nearly all food types and are antioxidants. Oxidation is the interaction between oxygen molecules and any other substance, including living tissue. It is constantly occurring in the cells of our body but oxidation reactions can also cause damage because at a molecular level they can give rise to “free radicals”, which are atoms or groups of atoms with an odd number of electrons, which can cause damage to cells that in turn can lead to chronic illness such as heart disease and cancer. The body therefore naturally produces anti-oxidants that neutralise “sweep up” these free radicals to prevent cells from becoming damaged but often not in sufficient quantities. The phenolic compounds in prunes had been found to inhibit human oxidation in vitro, and therefore may serve as preventive agents against chronic disease.
Prunes are also a good source of potassium (745 mg/100 g), which might be beneficial for cardiovascular health, iron, and boron, which may play a role in the prevention of osteoporosis. A serving of prunes (100 g) fulfils the daily requirement for boron (2 to 3 mg). Prunes also provide vitamin A in the form of beta-carotene. Research is on-going to assess the levels of carotenoids and other phytochemicals present in prunes.
See also - Does cooking destroy food micronutients
There has long been a search for a non-pharmacological alternative for treating osteoporosis. This form of bone degeneration is a highly debilitating disorder. Aside from existing drug therapies, certain lifestyle and nutritional factors are known to reduce the risk of osteoporosis. Among nutritional factors, recent observations suggest that prunes are the most effective fruit in both preventing and reversing bone loss.
According to the evidence-based studies (which are still fairly early), prunes have positive effects on bone indices. The data would indicate that dried plum may not only protect against bone degeneration, but also reverse bone loss. In addition to the animal studies, a 3-month clinical trial indicated that the consumption of prunes daily by postmenopausal women significantly increased serum markers of bone formation.
See also - Vitamin D article by Head of UK Vitamin D Reference Laboratory.
Increments in prune juice intake need to be very slow and carefully monitored until the desired effect is achieved. Sudden increases can often lead to unpleasant side effects like pain, cramping, gas and diarrhoea. Have patience as it takes a few days sometimes a few weeks for a very lazy bowel to adapt and relearn its function with respect to fibre.
Prune juice has a fruity sweet taste, often with hints of caramel.
If my digestive health is okay should/can I still drink prune juice; how much should I drink and how often?
Drinking a 120ml glass of prune juice every day for adults combined with drinking plenty of water every day (two litres every day including fruit juice, fruit or herbal teas) and regular exercise are all recommended as part of healthy life style.
The recommended guideline of 120ml per day is a rough guideline and can be adjusted according to effectiveness. If too much prune juice is being drunk the laxative effect may be too strong and could result in stomach cramps and loose motions.
Your GP and online sources such as Five A Day and Sunsweet. See also What Is Indigestion explained by Consultant Gastroenterologist.
You can download a full colour copy of this article for your own information or to show your GP. For further information please see Digestive Health and Prune Juice - The Natural Way.