Cranberry tablets: uses, dosage & background

Siski Green / 21 April 2020

The North American variety is used for juices, extracts, capsules and fresh and dried berries



Cranberry is most well known in the form of a delicious sauce for turkey and other meats. Its bright red appearance and fresh slightly tart flavour make it the perfect accompaniment. It is now grown in vast cranberry farms in North America, as well as in Chile in South America.

What is cranberry used for?

Cranberry juice, supplements or fruit is used to treat urinary tract infections or prevent them. It may also be useful in preventing tooth decay and it is also being investigated as a possible way to protect against certain digestive bacteria such as H.Pylori.

Aside from these medicinal benefits, cranberries, like many berries, contain high quantities of vitamin C, vitamin E and K1, manganese and copper. Cranberries are made up of nearly 90% water, along with fibre and carbohydrates. Cranberries, like so many other berries, are considered heart-healthy as they are so high in antioxidants. The insoluble and soluble fibre in cranberries can help your digestion if eaten in moderation, too.

What’s the history of cranberry?

Cranberries were eatan by Native Americans long before they were produced on an agricultural scale and made commercially available in the US and beyond. Native Americans used them in their foods and drinks, as well as medicinal remedies. They were even used in an early version of an energy bar, called ‘pemmican’ to keep fur traders’ energy levels up during the bitter winter months.

What’s the best way to take cranberry?

Cranberry juice, extracts, capsules, and fresh/dried berries are all products you can find relatively easily. Capsules and tablets contain higher concentrations of cranberry but processing the berries may remove some of the beneficial compounds. Juices may also contain a lot of sugar, so are best avoided. If you can find unsweetened cranberry juice drink 15-30ml per day, for fresh or frozen cranberries 40g twice a day, and capsules (with a 400mg dosage) can be taken twice a day (up to a maximum of 6 doses per day) is what is recommended to treat bladder infections and/or preventing them.

Fresh cranberries may be found in season (late May-June) in supermarkets but are most easily bought in frozen form. Cooked, canned cranberries (or those in cranberry sauce) have been heat-treated during processing so may not contain the same beneficial compounds as fresh.

Does cranberry really work?

Cranberry works by preventing bacteria from adhering to the bladder. By preventing this process, the bacteria can then be flushed out by your body. This means that essentially cranberry helps prevent bacteria from taking hold and producing symptoms such as pain while peeing or a desire to pee when you’ve just been (symptoms associated with UTIs). While cranberry may help relieve symptoms of a UTI you already have, you may need antibiotics to completely clear up the infection.

*Subs I used the term ‘pee’ rather than urinate as it seems to be more common on searches.

As cranberry fruit is rich in antioxidants such as quercetin, myricetin, and peonidin. Quercetin has been found to be a powerful anti-inflammatory, helping to prevent heart disease, fighting cancer cells and helping to control blood sugar levels.

The skin of cranberries also contain ursolic acid which has anti-inflammatory effects and may contribute to the cranberry’s ability to help relieve symptoms of UTI. A-type proanthocyanidins are also thought to contribute to the UTI-fighing effects of cranberries.

What are the side effects of cranberries?

For most people taking cranberry supplemtns or drinking juice, eating the fruit regularly won’t cause any problems. Eating large quantities (more than two or three handfuls of berries in one sitting) may cause stomach upset, and drinking large quantities (more than a litre a day) may raise your risk of kidney disorders.

Are there any contraindications with cranberries?

If you have prone to kidney stones, it is best to avoid cranberry products as they contain high levels of oxalates

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The material is for general information only and does not constitute investment, tax, legal, medical or other form of advice. You should not rely on this information to make (or refrain from making) any decisions. Always obtain independent, professional advice for your own particular situation.