Increasing your daily intake of magnesium may protect against age-related brain shrinkage, white-matter lesions and the risk of dementia.
This is according to new research from the Neuro-imaging and Brain Lab at Australian National University (ANU).
The protective benefits, gained from eating magnesium-rich foods such as nuts and spinach, were particularly marked in women.
Dementia and deficiency
Previous studies found that people with Alzheimer’s disease commonly have lower levels of magnesium in their brains. They also have less magnesium in their hair, indicating magnesium deficiency.
Further, the ANU authors point to studies that suggests dietary magnesium is associated with better cognitive function and may reduce the risk of developing dementia.
However, they note that it’s unclear when dietary magnesium intake “starts contributing to brain health and in what way”.
Overall, research exploring the link between magnesium and dementia is relatively new.
What is magnesium?
Magnesium is a metal found in every cell in your body.
Without magnesium you wouldn’t function.
Magnesium is what’s known as a co-factor, or helper molecule. It plays a role in more than 600 biochemical reactions performed by enzymes.
Some examples: Magnesium helps converts food to energy; creates new proteins from amino acids, and helps in genetic maintenance.
Also, and relevant to brain research, it regulates neuro-transmitters.
People with magnesium deficiencies are at greater risk of developing high blood pressure, heart disease, stroke, type 2 diabetes, osteoporosis and migraines.
Magnesium is obtained from food or supplements.
The foods rich in magnesium are the kind of healthy foods most people don’t get enough of: green leafy vegetables, legumes, nuts and seeds, and whole grains.
How much do you need?
According to the federal Department of Health, men aged under 30 need 400 milligrams (mg) of magnesium per day. Men over 31 need 420mg a day, women under 30 need 310mg each day and those over 31 need 320mg a day.
Pregnant and breastfeeding women need 350 to 360mg a day.
To get the benefits suggested in the ANU study, you would need to consume significantly more than what is recommended in the guidelines.
The study
The study involved more than 6000 cognitively healthy participants in the United Kingdom. The participants were aged 40 to 73.
They were asked to complete an online questionnaire five times over a period of 16 months.
The responses were used to calculate the daily magnesium intake of participants and were based on 200 different foods with varying portion sizes.
The ANU team focused on magnesium-rich foods such as leafy green vegetables, legumes, nuts, seeds and whole grains to provide an average estimation of magnesium intake from the participants’ diets.
The participants had their brains scanned by MRI. These scans revealed brain shrinkage and white lesions.
The results
Participants who consumed more than 550 milligrams of magnesium each day “had a brain age that was approximately one year younger by the time they reached 55”.
This was compared with someone with a normal magnesium intake of about 350 milligrams a day.
“Our study shows a 41 per cent increase in magnesium intake could lead to less age-related brain shrinkage, which is associated with better cognitive function and lower risk or delayed onset of dementia in later life,” said lead author and PhD researcher Khawlah Alateeq.
Ms Alateeq said the neuro-protective effects of more dietary magnesium “appears to benefit women more than men and more so in post-menopausal than pre-menopausal women, although this may be due to the anti-inflammatory effect of magnesium”.
Bottom line: More nuts, beans, leafy greens, seeds and whole grains.
Magnesium is great for all your body, not just your brain.
