Nutrition: September 2008 Archives
From "The Sun"
September 12, 2008 07:45pm
SCIENTISTS have discovered that going veggie could be bad for your brain - with those on a meat-free diet six times more likely to suffer brain shrinkage.Vegans and vegetarians -- such as Heather Mills -- are the most likely to be deficient because the best sources of the vitamin are meat, particularly liver, milk and fish.
Vitamin B12 deficiency can also cause anaemia and inflammation of the nervous system.
Yeast extracts are one of the few vegetarian foods which provide good levels of the vitamin.
The link was discovered by Oxford University scientists who used memory tests, physical checks and brain scans to examine 107 people between the ages of 61 and 87.
When the volunteers were retested five years later the medics found those with the lowest levels of vitamin B12 were also the most likely to have brain shrinkage. It confirms earlier research showing a link between brain atrophy and low levels of B12.
GO EASY ON THE BOOZE
Brain scans of more than 1,800 people found that people who downed 14 drinks or more a week had 1.6 per cent more brain shrinkage than teetotallers.
Women in their seventies were the most at risk.
Beer does less damage than wine according to a study in Alcohol and Alcoholism.
Researchers found that the hippocampus - the part of the brain that stores memories -- was 10 per cent smaller in beer drinkers than those who stuck to wine.
And don't inhale, cannabis has been shown to have the same brain-rotting effect.
Being overweight or obese is linked to brain loss, Swedish researchers discovered.
Scans of around 300 women found that those with brain shrink had an average body mass index of 27
And for every one point increase in their BMI the loss rose by 13 to 16 per cent.
A BMI 25 to 30 is classed as overweight, above 30 is clinically obese. Calculate your BMI
Dr Deborah Gustafson of University Hospital in Göteborg says obesity increases the risk of high blood pressure and cardiovascular disease, which are both thought to contribute to brain drain.
She adds: "Obesity may also increase the secretion of cortisol, which could lead to atrophy."
The omega-3 oils found in fish reduce the risk of dementia and other mental disorders says Fernando Gómez-Pinilla of the University of California, Los Angeles.
He says they increase flexibility in synapses in the brain - the bits that transmit information - and boost memory and learning.
Vitamin B12 status and rate of brain volume loss in community-dwelling elderly
From OPTIMA (A.V., H.R., C.J., K.M.B., C.d.J., M.M.B., A.D.S.), Department of Physiology, Anatomy and Genetics, University of Oxford, UK; Institute of Basic Medical Sciences (A.V., H.R.), Department of Nutrition, University of Oslo, Norway; Oxford University Centre for Functional MRI of the Brain (S.M.S.), UK; and Department of Geriatric Medicine (M.M.B.), The Canberra Hospital and Australian National University Medical School, Australia.
Address correspondence and reprint requests to Anna Vogiatzoglou, Department of Physiology, Anatomy and Genetics, University of Oxford, Le Gros Clark Building, South Parks Rd., Oxford OX1 3QX, UK email@example.com
Objectives: To investigate the relationship between markers of vitamin B12 status and brain volume loss per year over a 5-year period in an elderly population.
Methods: A prospective study of 107 community-dwelling volunteers aged 61 to 87 years without cognitive impairment at enrollment. Volunteers were assessed yearly by clinical examination, MRI scans, and cognitive tests. Blood was collected at baseline for measurement of plasma vitamin B12, transcobalamin (TC), holotranscobalamin (holoTC), methylmalonic acid (MMA), total homocysteine (tHcy), and serum folate.
Results: The decrease in brain volume was greater among those with lower vitamin B12 and holoTC levels and higher plasma tHcy and MMA levels at baseline. Linear regression analysis showed that associations with vitamin B12 and holoTC remained significant after adjustment for age, sex, creatinine, education, initial brain volume, cognitive test scores, systolic blood pressure, ApoE 4 status, tHcy, and folate. Using the upper (for the vitamins) or lower tertile (for the metabolites) as reference in logistic regression analysis and adjusting for the above covariates, vitamin B12 in the bottom tertile (<308 pmol/L) was associated with increased rate of brain volume loss (odds ratio 6.17, 95% CI 1.25-30.47). The association was similar for low levels of holoTC (<54 pmol/L) (odds ratio 5.99, 95% CI 1.21-29.81) and for low TC saturation. High levels of MMA or tHcy or low levels of folate were not associated with brain volume loss.
Conclusion: Low vitamin B12 status should be further investigated as a modifiable cause of brain atrophy and of likely subsequent cognitive impairment in the elderly.
Abbreviations: AD = Alzheimer disease; CAMCOG = Cambridge Mental Disorders of the Elderly Examination; CV = coefficient of variation; holoTC = holotranscobalamin; MMA = methylmalonic acid; NS = not significant; OPTIMA = Oxford Project to Investigate Memory and Aging; OR = odds ratio; PBVL = percentage of brain volume loss; SIENA = structural image evaluation using normalization of atrophy; TC = transcobalamin; tHcy = total homocysteine.
Supplemental data at www.neurology.org
Supported by Alzheimer's Research Trust (UK), the Medical Research Council, the Charles Wolfson Charitable Trust, the Norwegian Foundation for Health and Rehabilitation through the Norwegian Health Association, Axis-Shield plc, and the Johan Throne Holst Foundation for Nutrition Research.
Disclosure: The authors report no disclosures.Received December 12, 2007. Accepted in final form June 4, 2008.