Showing posts with label cranberry juice. Show all posts
Showing posts with label cranberry juice. Show all posts

Monday, 20 April 2015

Acid reflux - alkaline diet?

The growth of the Internet has enabled health myths to spread around the globe like a virulent strain of flu, infecting websites, books and the beliefs people hold about their health.

One of the most prevalent is the alkaline/acid diet myth. This seems to have come about as a result of an unfortunate marriage between Western alternative ideas about nutrition and Oriental concepts about the medicinal effects of foods. There is no evidence to support the idea that following a diet dictated by these notions can prevent any illnesses, cure any diseases or improve health in any way. The pseudo-scientific explanation of those who preach this doctrine talks about acid-forming and alkaline-forming foods (sometimes referred to as acid and alkaline foods for short).

One of the most confusing aspects is that an apparently arbitrary list of foods that supposedly makes your blood more acidic or alkaline. If you take fruits for example, citrus fruits are considered “alkalising” while cranberries and plums are considered “acidifying”.  This leads to statements like “lemons alkalise the blood”. In reality the chemistry of the blood is self-regulating and can withstand people consuming pints of orange juice or several antacid tablets in a day. These dietary recommendations have nothing whatsoever to do with whether the food has an acidic taste or contains any actual acids, such as citric acid or ascorbic acid. Or indeed, whether they a high or low pH.  An important scientific word has been seized and shaken it until it is unrecognisable.


This belief system is doubly confusing when it is used to advise people suffering from acid-reflux. Someone taking medicine aimed at neutralising their stomach acid, or reducing its production by the glands of the stomach, really does not need this muddle-headed pseudo-science thrown into the mix. Yet there are many books and websites that promote these dietary ideas to this group of patients.


Reflux is caused by a weakness of the valve at the top of the stomach and not by an imbalance of the pH of the blood. There is very little evidence that any particular foods have a consistent effect on reflux symptoms. The best way for an individual to check if something disagrees with them is to give up just one food at a time, eat normally, and then re-introduce the suspect food for a day and note any effects. Then, as with all good scientific experiments, repeat this procedure a few times to check that the effect is consistent.


Other than that, reflux patients should eat a high-fibre diet which seems to help, possibly because it keeps constipation and straining at bay. Straining, in someone with a weakened valve, will tend to push acid back up the oesophagus. The other important point is to eat a diet that prevents, or reduces any tendency to develop a bulging waistline. In this way pressure on that problematic valve will be kept to a minimum.

Friday, 7 December 2012

Cranberry Juice – Can it Cure or Prevent Cystitis?


For several decades now there has been a health rumour circulating that cranberry juice can cure urinary tract infections (cystitis) or have a preventative effect in those who tend to suffer multiple attacks. Such health rumours are extremely popular with the “health columns” of many newspapers and magazines. There is an obvious appeal in the idea that something natural and fruity will act like a medicine. But is there any evidence to back these claims?
If you want to know the answer to questions like this, the oracle is Cochrane. Many scientists publish reviews of literature. Sometimes they are thorough. Sometimes they are biased in support a particular theory. The Cochrane Collaboration, on the other hand, publish systematic reviews. These are exhaustive examinations of the literature carried out by volunteers from the ranks of medical scientists. They leave no stone unturned in their search for studies. Then they select the studies that involve well-conducted trials (randomised, controlled trials with a placebo) on human beings. They look at these carefully and determine whether the sum of the results tend to show any clear evidence.
The fact that they look at human studies is important. Lab data from cells in dishes or from mice are often cited but neither of these tell you whether something works in a human being. In the case of cranberries there is some lab evidence that cranberry juice contains a chemical that can discourage bacteria from sticking to the wall of the bladder. But does this translate into practice?
In a recently updated Cochrane review the authors failed to detect any clear effect of cranberry products in preventing cystitis in susceptible people. In a review in 2010 the Cochrane team found no well-conducted studies on cranberry products as a treatment.
There was a problem with a high drop-out rate from the studies. Consuming cranberry juice in sufficient quantities, every day, to maintain a high level of cranberry chemical in your urine is not easy. The juice is acidic and sugary. The implications for dental health are obvious and as I posted previously, consuming a lot of juice is not necessarily a Good Thing.  
If you don’t want to read scientific reviews and you’re wondering whether some food or drink has a proven health benefit, I suggest you read the packaging carefully. It may refer vaguely to something that sounds healthy – but does it clearly say there is a proven benefit to a specific aspect of health? If not, you can be confident that no convincing case has been made to the regulatory agencies.
There is a long list of food products that would dearly love to prove they have health benefits but the list of those that do is an extremely short one.