Sunday, September 15, 2013
Garlic can lower blood pressure by 10%... but only if you take it in tablet form
Meta-analyses are hard to evaluate but the effect is in any case very weak -- and no mortality or morbidity effects appear to have been demonstrated
Twelve weeks of treatment with garlic tablets led to a ‘significant’ cut in blood pressure, slashing the risk of a heart attack or stroke, according to a review of evidence.
Researchers claim those with hypertension, or high blood pressure, could control their condition better by adding garlic to conventional medication.
The review of 21 studies on humans found supplements of dried garlic containing a guaranteed dose of the active ingredient allicin consistently led to reductions in blood pressure.
But eating the real thing would not have the same effect, says the review. Although allicin is produced when raw garlic is crushed or chewed, much of it is destroyed during cooking.
The tablets also have the significant advantage of not producing the bad breath associated with eating fresh garlic.
The review looked at supplements with a guaranteed allicin yield of 1.8mg per dose.
The earliest authoritative clinical trial to be published in 1990 found taking Kwai brand garlic tablets led to a significant fall in blood pressure of 10 per cent within 12 weeks.
More studies conducted since 1990 have demonstrated significant blood pressure lowering effects from dried garlic releasing allicin at 1.8mg per dose.
Not all garlic preparations release allicin in significant, standardised amounts, says the review by nutritionist Dr Pamela Mason in the journal Complete Nutrition.
A trial comparing garlic oil versus standardised dried garlic failed to show a blood pressure lowering effect with the oil, but blood pressure again fell significantly with dried garlic.
Around 16million Britons have high blood pressure, including the third who do not know they have it. It is a major risk factor for heart disease, stroke, and kidney failure.
Garlic is thought to counter high blood pressure because it stimulates production of the chemicals nitric oxide and hydrogen sulphide, which helps relax blood vessels.
Dr Catherine Hood, an independent expert in nutrition and dietetics, said: ‘This review found evidence that garlic, in particular Kwai, can reduce the stickiness of the blood, results in dilatation of the arteries and has antioxidant activity.’
Dr Hood said there was some evidence garlic may also use the same mechanism as drugs called ACE inhibitors to lower blood pressure.
The drugs stop the body creating a hormone known as angiotensin II. This has a variety of effects but essentially relaxes blood vessels.
Nutritionist Sarah West said other research suggests allicin helps lower ‘bad’ LDL cholesterol and triglycerides – a common form of fat.
She added: ‘It would be very difficult to get a therapeutic dose from eating raw garlic, it would need 30 cloves at one sitting – and we don’t actually have the evidence that it would work.
‘The allicin content of raw garlic varies enormously and a significant drawback is the odour on the breath – a problem you don’t get with tablets.’
Does being fat cause headaches? Obese people are almost TWICE as likely to suffer migraines than those who are slim
Childishly naiive research. Poor people are fatter and have worse health. The finding is simply the usual class effect
Being seriously overweight can nearly double a person’s chances of suffering migraines, a study has found.
The disabling condition affects one in seven adults and costs the UK economy an estimated £2billion a year. Now scientists have found a link with weight.
They discovered that obese people were 81 per cent more likely to have episodic migraines than those of normal weight.
Episodic migraines affect the vast majority of sufferers, who have the severe headaches for less than 15 days a month. In contrast, those with chronic migraines feel unwell for more than half the days in the month.
The research suggests that weight loss and exercise could help those who suffer from migraines. The findings also indicated the link between the condition and obesity is stronger in those under the age of 50.
‘Previous studies have shown a link between people with chronic migraines and obesity, but the research has been conflicting on whether that link existed for those with less frequent attacks,’ said researcher Dr Barbara Lee Peterlin, of Johns Hopkins University School of Medicine in Baltimore.
‘As obesity is a risk factor that can potentially be modified and since some medications can lead to weight gain or loss, this is important for people with migraines and their doctors.’
For the study, 3,862 people with an average age of 47 filled out surveys with information on height, weight and migraines.
A total of 1,044 participants were obese and 188 of the participants had occasional, or episodic, migraine, which is defined as 14 or fewer migraine headaches per month.
Obese people were 81 per cent more likely to have episodic migraine of any frequency as compared to people of healthy weight.
Dr Peterlin said: ‘These results suggest that doctors should promote healthy lifestyle choices for diet and exercise in people with episodic migraine.
‘More research is needed to evaluate whether weight loss programmes can be helpful in overweight and obese people with episodic migraine.’
The results also showed that the link was stronger in those under 50, when migraine is most prevalent.
Posted by jonjayray at 12:24 AM