Tuesday, November 12, 2013
Kidney risk of two fizzy cans a day: Sugar used in drinks raises blood salt levels
If you are a rat
Just two fizzy drinks a day can damage the kidneys, research shows.
One study revealed how the type of sugar used in such drinks apparently raises blood salt levels.
A second showed that the drinks may cause the kidneys to get rid of too much protein from the body.
A hallmark of failing kidneys is called proteinuria – the increased excretion of protein in the urine.
It was found in those who had two of the drinks daily in a study at Osaka University Graduate School of Medicine in Japan.
More than 8000 university employees with regular kidneys took part in the experiment.
A third abstained from fizzy drinks, another third drank one a day, and the final group had two a day.
In a space of just three days, 10.7 per cent of the third group developed proteinuria, and 8.9 per cent of the second group showed similar effects.
The first group just showed signs in 8.4 per cent of those tested.
Fructose or fruit sugar is used to sweeten soft drinks and researchers for the second study at Case Western Reserve University in Cleveland found that it increases the kidneys’ sensitivity to angiotensin II, a protein that regulates salt balance.
It means salt is reabsorbed into the kidneys, which could lead to diabetes, obesity, kidney failure, or hypertension.
Researchers hailed the tests, on rats, as a potential indication of what is causing epidemics of these illnesses.
Both studies were presented at the American Society of Nephrology Kidney Week in Atlanta last week.
HRT could help help prevent embarrassing 'senior moments' when the pressure is on
The rehabiliitation of HRT goes on
Taking Hormone Replacement Therapy could help prevent older women from suffering embarrassing ‘senior moments’.
Levels of the hormone oestrogen plummet around the menopause, but a study suggests that replacing it helps keep the mind sharp when under pressure.
Women with high levels of oestrogen did as well on a memory test when stressed out as when relaxed, but others were forgetful when pressurised.
The U.S. study tested 42 post-menopausal women, half of whom had been taking HRT for about five years, on their working memory.
This is the type of memory we use to hold one thing in mind while doing something else – for instance, remembering a phone number while asking someone for a pen and paper.
To put the body under stress, the women held their hands in a bucket of icy water for three minutes.
They then did a test of working memory in which they had to remember lists of words while reading sentences and checking them for grammatical errors.
The test was also done in more relaxed circumstances, in which the bucket was filled with pleasantly warm water.
Women with low levels of oestrogen did much worse on the memory test when their hands were cold.
However, those with high levels of the hormone didn’t falter, the Society for Neuroscience’s annual conference heard.
Saliva samples showed that levels of the stress hormone cortisol shot up in the women with low oestrogen – but only rose slightly in those with large amounts of the sex hormone.
Researcher Alexandra Ycaza said her findings suggest oestrogen helps protect the brain from the effects of stress.
The fall in oestrogen that occurs with age means that older women lose this ‘built-in protection’.
Miss Ycaza, a PhD student: ‘If you are taking oestrogen after menopause, you may have some kind of protection from the effects of stress on memory.
‘It may be as simple as higher oestrogen reduces the amount of cortisol released and so there is less of the stress hormone around to affect memory processing.’
She stressed that health concerns surrounding HRT mean any women considering starting it should discuss the issue carefully with their doctor.
The drug is very effective at easing the symptoms of menopause and can cut the odds of brittle bones and bowel cancer, according to the NHS.
It warns that HRT slightly increases the risk of stroke, breast cancer and ovarian cancer and cancer of the lining of the womb but says that if taken for under five years, most experts agree that the benefits outweigh the risks.
Miss Ycaza added that controlling stress may have benefits beyond improved memory.
‘Stress, whether at home or at work, can have negative effects on the body and brain, hurting and killing brain cells and producing problems with mood, memory and sleep,' she said.
‘Women who are going through the menopause or post-menopause are still working and raising families and these are stressful daily life events.
‘Discovering factors that might protect people from stress could have huge impacts on how people perform in their daily lives from work, to relationships at home.’
Posted by jonjayray at 12:20 AM