Niki Bezzant: The diet for a healthy brain

Every three seconds around the world someone develops dementia, according to Alzheimers NZ. Photo / 123RF

COMMENT: A lot of things about getting older are great. We gain experience and insight, we get wiser. We often become more comfortable in our skins — research has consistently shown people to be happiest when in their late 60s and older.

The theory is that we become more accepting of ageing and become more content with our financial situation, physical appearance and general wellbeing.

One of the less great things about getting older is the risk of losing our cognitive function: The spectre of dementia.

This is probably the main thing that scares me when I think about the prospect of living a long time. If I'm lucky enough to get to be an old lady, I want to be one who knows what's going on around me.

Dementia, though, is something which will affect most of us at some stage. Every three seconds around the world someone develops dementia, according to Alzheimers NZ.

Here in New Zealand, four out of five Kiwis are affected — and the current figure of 60,000 people living with dementia is expected to triple by 2050. In World Alzheimer's Month, the organisation says it's time to get our heads around dementia, and lessen the stigma associated with the disease.

Dementia is a catch-all term for a range of symptoms relating to how well our brains work. Alzheimer's disease is the most well-known and most common form of dementia. Once we have dementia, it can be managed, but it's progressive.

In terms of prevention, though, some interesting research is emerging that's worth thinking about.

There's an association between inflammation and dementia. It's thought that low-level inflammation affects brain function over time. Inflammation is related to diet and lifestyle: High-sugar, bad-fat processed foods, lack of exercise, smoking and drinking ramp it up.

By contrast, there's an association between the whole-food Mediterranean diet — high in vegetables, whole grains, nuts and seeds, olive oil and fish — and a lower risk of cognitive decline. Eating less sugar and red meat is also associated with a lower risk. And the old foes, alcohol and smoking, also increase our risk.

Although red wine has been promoted as health-boosting, that's overstating its benefit, according to experts. The UK Alzheimer's Society says that regularly drinking more than recommended amounts of alcohol can cause brain damage and increase our risk of dementia.

If you're looking to reduce dementia risk, they say, starting drinking is not the way to do it.

At the frontiers of dementia research, probiotics are showing some promise. A 2016 trial found improved cognition in Alzheimer's patients who were given probiotics. More recent work has also highlighted the "gut-heart-brain axis", raising the fascinating possibility that altering the bacteria in the gut might affect not only our risk of developing dementia, but may also be able to reverse some of its effects.

For now, though, for those of us looking to future-proof our brains we're wise to look to the longest-lived people in the world who eat according to the old wisdom: Food, not too much, mostly plants.

• Niki Bezzant is editor-at-large for Healthy Food Guide www.healthyfood.co.nz