A new study suggests high doses of B vitamins may halve the rate of brain shrinkage in older people experiencing some of the warning signs of Alzheimer’s disease.
Brain shrinkage is one of the symptoms of mild cognitive impairment, which often leads to dementia.
Researchers say this could be the first step towards finding a way to delay the onset of Alzheimer’s.
Experts said the findings were important but more research was needed.
A tablet, costing as little as 10p a day and made up of three vitamin B supplements, cut brain shrinkage linked to memory loss by up to 500 per cent.
Oxford University researchers behind the landmark study said it offered the ‘first glimmer of hope’ in the battle to find a drug that slows or stops the development of Alzheimer’s.
It and other forms of dementia blight the lives of more than 800,000 Britons, and the number of cases is expected to double within a generation.
No previous drug trials have been successful and, with around 500 new cases of Alzheimer’s diagnosed every day in the UK alone, anything that delays the development of the disease could improve the lives of millions.
The breakthrough centres on a compound called homocysteine which is naturally made in the body and, at high levels, has been linked to memory loss and Alzheimer’s.
Vitamin B is known to break down homocysteine, so the researchers decided to look at whether giving patients the vitamin would be good for memory.
Working with colleagues in Norway, the Oxford team recruited 270 pensioners suffering from slight memory lapses that can be a precursor to Alzheimer’s.
Known as mild cognitive impairment, or MCI, it affects one in six aged 70-plus, or 1.5million Britons.
Half of those with MCI will develop dementia within five years of diagnosis. Half of those taking part in the trial took a vitamin B tablet a day for two years.
The tablets contained extremely high doses of vitamins B6, 9 and 12.
For instance, the amount of B12 was up to 300 times higher than could be obtained by simply eating bananas, meat, wholegrains, beans and other foods rich in the vitamin.
The others took a daily dummy pill with no active ingredients.
Brain scans were carried out to check if the pill reduced the shrinkage of the brain that happens naturally as we age and speeds up in memory loss.
Vitamin B cut the amount of shrinkage by 30 per cent, on average, the journal PLoS ONE reports.
The B vitamins are eight water-soluble vitamins that play important roles in cell metabolism. The B vitamins were once thought to be a single vitamin, referred to as vitamin B (much as people refer to vitamin C or vitamin D). Later research showed that they are chemically distinct vitamins that often coexist in the same foods. In general, supplements containing all eight are referred to as a vitamin B complex. Individual B vitamin supplements are referred to by the specific name of each vitamin (e.g., B1, B2, B3 etc.).
List of B vitamins
* Vitamin B1 (thiamine)
* Vitamin B2 (riboflavin)
* Vitamin B3 (niacin or niacinamide, sometimes also known as vitamin PP)
* Vitamin B5 (pantothenic acid)
* Vitamin B6 (pyridoxine, pyridoxal, or pyridoxamine, or pyridoxine hydrochloride)
* Vitamin B7 (biotin)
* Vitamin B8 (inositol)
* Vitamin B9 (folic acid)
* Vitamin B12 (various cobalamins; commonly cyanocobalamin in vitamin supplements)
The B vitamins may be necessary in order to:
* Support and increase the rate of metabolism
* Maintain healthy skin and muscle tone
* Enhance immune and nervous system function
* Promote cell growth and division, including that of the red blood cells that help prevent anemia
* Reduce the risk of pancreatic cancer – one of the most lethal forms of cancer – when consumed in food, but not when ingested in vitamin tablet form.
All B vitamins are water-soluble, and are dispersed throughout the body. Most of the B vitamins must be replenished regularly, since any excess is excreted in the urine.