GBN Health Check: What are the best supplements for your brain as you get older? Scientists give their verdict
Scientists explain the latest evidence on supplementation and brain health
Getty Images
Your brain is your most powerful organ. The complex network of neurons governs everything you care about, from thinking to behaviour.
And yet, it's constantly under threat from age, genetics and lifestyle.
Thankfully, there's growing evidence that the brain maintains the ability to change and adapt.
This is where supplements come in. Studies suggest you can supplement your way to better brain health.
Identifying the pool of candidates has become psychologist and author Patrick Holford's abiding mission.
He is the founder of Food for the Brain, a non-profit made up of more than 20 scientists who are dedicated to exploring the science behind diet and cognitive health.
B vitamins
According to Mr Holford, the single most effective evidence-based intervention is lowering homocysteine with B vitamins.
Homocysteine is a toxic amino acid that accumulates when there is a lack of B vitamins in your body. It damages your brain as well as your arteries.
A high homocysteine level is a biomarker for over 100 diseases, especially those of the central nervous system.
For example, it's a biomarker of impaired cognitive abilities in children and in adults and is a risk marker for stroke and for dementia and Alzheimer’s, but also possibly for depression, anxiety, bipolar, schizophrenia, obsessive-compulsive disorder, Parkinson’s and multiple sclerosis.
A raised homocysteine level therefore means something is going wrong with a vital process that controls how we think, feel and perceive.
And it's entirely dependent on B vitamins.
Some people absorb B12 less well. Others just need more of the B vitamin than others and that biochemical individuality, especially if their diet is already deficient, "can tip them into a mental or neurological illness", warns Mr Holford.
Indeed, "it is very much the forgotten factor, and is easily corrected", explained pharmacology professor David Smith FMedSci, formerly Deputy Head of the Faculty of Medical Sciences at the University of Oxford.
The best evidence of the cognitive benefits of B vitamins comes from a meta-analysis published in the British Medical Journal.
The systematic review and meta-analysis of 243 observational prospective studies and 153 randomised controlled trials concluded that lowering homocysteine with B vitamins is the most promising intervention preventing Alzheimer's disease.
Vitamin B helps lower homocysteine - a toxic amino acid that's a biomarker for over 100 diseases
Getty Images
Enhance with omega-3
The combined effect of omega-3 and B vitamins is greater than either nutrient on its own, research suggests.
Oxford University researchers recently revisited a study on people with pre-dementia and looked at the blood levels of omega-3 at the start of the study.
They were not given omega-3. They were given B vitamins or a placebo, and they found something unique. Those with low omega-3 status have no benefit from the B vitamins.
Yet those with high omega-3 status had 73 percent less brain shrinkage.
In fact, it may be possible to prevent up to 80 percent of dementia cases if all known risk factors, including homocysteine-lowering B vitamins and omega-3, found in oily fish, were targeted, reckons Professor Yu of Fudan Univeristy in Shanghai.
Another meta-analysis of 14 studies published in the British Journal of Nutrition found those aged 60-70 who supplemented with a combination of B vitamins and omega-3 fats had less cognitive decline than those who did not.
The research, which included a total of 4913 people who were followed up between six months and four years concluded: “Increasing intake of both nutrients benefits cognition in older adults compared to placebo."
How does supplementing with omega-3 help?
The three main omega-3 fatty acids are alpha-linolenic acid (ALA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA).
"Adequate levels of DHA in particular are crucial for maintaining optimal brain function, including learning and memory processes," explained Amy Reichelt, Chief Innovation Officer at PurMinds Neuropharma.
According to Ms Reichelt, DHA is a major structural component of neuronal membranes which maintains their fluidity and flexibility, which is essential for neuronal communication via neurotransmitter receptors that are expressed on the cell membrane.
EPA and DHA have been shown to affect the levels of neurotransmitters such as serotonin and dopamine, which play key roles in mood regulation, cognition, and behaviour.
"Omega-3s also have anti-inflammatory and neuroprotective properties, helping to reduce inflammation in the brain," explained the Chief Innovation officer.
Chronic inflammation in the brain has been linked to various neurological conditions, including Alzheimer's disease.
By reducing inflammation and protecting neurons from oxidative stress, it's thought omega-3s may help protect against age-related cognitive decline and neurodegenerative diseases and support overall brain health.
LATEST DEVELOPMENTS
Omega-3s may help protect against age-related cognitive decline
Other promising supplements
Increasing evidence suggests that vitamin D may also play a role in maintaining cognitive function.
A large-scale study supported by the National Institute for Health and Care Research (NIHR) Exeter Biomedical Research Centre found that taking vitamin D was associated with living dementia-free for longer, and they also found 40 percent fewer dementia diagnoses in the group who took supplements.
However, other studies have not identified this association and the mechanisms are unclear.
Likewise, vitamin C may play a protective role against Alzheimer's Disease and cognitive impairment. In a recent review of 50 studies of vitamin C levels and cognitive function, all conducted between 1980 and January 2017, Australian researchers found a striking relationship between vitamin C status and mental function,
The antioxidant protects the brain from damage and helps create neurotransmitters. And vitamin C deficiency, including scurvy, has been linked to depression and cognitive impairment.
However, more studies are needed to confirm this association.
Exercise has been linked to improvements in thinking and memory, and reduced rates of dementia
GETTY IMAGESWhat else can be done to protect brain health?
It's important to remember that there is no single pill that can improve brain health in the face of consuming a poor diet.
Supplements are there to fill any nutritional gaps in a diet, but you can’t just eat a bad diet and take supplements to feel better.
A holistic approach offers the best defence against brain decline.
Studies looking at the effect of exercise in middle-aged or older adults have reported improvements in thinking and memory, and reduced rates of dementia.
To stay healthy, the UK Chief Medical Officers' Physical Activity Guidelines state that adults should try to be active every day and aim to do at least 150 minutes of physical activity over a week, through a variety of activities.
Eating a brain-healthy diet can also help slow the advance of cognitive decline.
The Mediterranean-DASH Intervention for Neurodegenerative Delay diet was designed with this purpose in mind.
The MIND diet combines elements of the Mediterranean diet and the Dietary Approaches to Stop Hypertension (DASH) diet.
It emphasises plant-based foods (especially berries and leafy greens) and limited consumption of animal products and saturated fats.
Studies have linked greater adherence to the diet with reduced risk of dementia.
But it has also been shown to benefit heart health, diabetes, and certain cancers.