While experts don’t yet understand exactly what causes neurodegenerative diseases such as Alzheimer’s, it’s thought that there’s a link with a build-up of waste proteins in your brain. And researchers at Penn State University in the US have discovered that when you tighten your abdominal muscles, they press on blood vessels connected to your spinal cord and brain, leading to movement that encourages the flow of fluid in and around your brain – which might help to flush out this waste.

'Smell training’ is being trialled as a way to slow down dementia. In one US study, older people who were exposed to new scents each night saw a 226% improvement in memory tests after six months. ‘Smell has a direct relationship with the brain,’ says cognitive strategist Natalie Mackenzie. 
 

‘The olfactory nerve connects directly to the hippocampus and amygdala – the brain regions most central to memory formation. This direct connection has significant implications for cognitive health.’ So, exercise your nose like you do your muscles: sniff fruit and vegetables when buying them, practise identifying notes in perfume, and seek out new smells every day.

Shingles is a painful condition caused by the chickenpox virus being reactivated after lying dormant in your body. The virus can damage neurons in your brain, which could raise the risk of dementia – but a Welsh study found vaccinated people were 20% less likely to get dementia over the next seven years. ‘To anyone over 50, I would say: get the shingles vaccine now,’ says Professor John Todd, who’s researching the link at the University of Oxford. ‘You want to reset your immune system as soon as possible.’ If you’re 65-79, you can usually get the vaccine on the NHS.

A study in the US found that people who followed an anti-inflammatory, Mediterranean-style eating plan had fewer signs of Alzheimer’s in their brains. ‘It involves primarily choosing oily fish, lentils and pulses as protein sources,’ says Rebecca McManamon, spokesperson for the British Dietetic Association. ‘Daily green leafy vegetables and berries are prioritised, and wholegrain carbohydrates should be picked over more processed ones.’ For more details, see The Official MIND Diet by Dr Martha Clare Morris 
(Little, Brown, £25). You can also explore our fish recipes and pulses and grains recipes.

High blood pressure is a risk factor for cognitive decline. ‘Over time, it makes blood vessels thicker, stiffer and narrower, reducing blood flow to the brain,’ explains Dr Pauline Swift, chair of Blood Pressure UK. ‘It can also increase the risk of strokes and the build-up of small vessel damage in the brain, which may affect memory and thinking.’ Very low blood pressure has also been linked to an increased risk of Alzheimer’s. ‘A reading around 120/80mmHg is generally considered healthy, but discuss your own targets with your GP,’ advises Pauline.

A recent study from the US’s Rush University found older people who socialise frequently – whether that’s dining with friends, being in a book club or going to church – have a 38% lower risk of dementia. ‘Being around others engages a number of cognitive systems,’ says Natalie. ‘Conversation requires listening, processing, retrieving vocabulary, formulating responses and reading social cues. Even the warmth and laughter of a good social gathering is doing something important neurologically.’

Not only can carrying extra pounds raise your blood pressure, but recent research also suggests that obesity increases the rate at which potentially harmful proteins collect in your brain and may independently raise the risk of Alzheimer’s. In the study, people with obesity saw Alzheimer’s markers in their blood increase up to 95% faster than people without obesity. They developed waste build-up more quickly, too.

One study found 70-year-olds who’d had gum disease for more than 10 years were 70% more likely to get dementia than those who hadn’t. It’s suspected that the condition causes inflammation that affects the brain. ‘Spend two minutes brushing and one extra minute cleaning between your teeth with products such as interdental brushes,’ says Miranda Pascucci, dental hygiene therapist and head of clinical education at TePe. ‘Most gum disease starts between the teeth.’

In a large-scale US study, people aged under 75 who drank two to three cups of coffee a day saw their dementia risk drop by 35%. Don’t go overboard, though – if the caffeine impacts your sleep, it could have the opposite effect. ‘Sleep is when the brain consolidates memory, clears metabolic waste and restores the cognitive system you depend on every day,’ says Natalie.

ur levels start to fall from October, but a recent study found that people with high levels of vitamin D in midlife had lower levels of tau protein (one of the proteins that can build up in the brain) in later life. The results need further investigation, but they ‘suggest that higher vitamin D levels in midlife may offer protection against developing these tau deposits’, says researcher Dr Martin David Mulligan at the University of Galway.