How your friends reduce your risk of dementia.

Friends and socialising

The days are long, but the years are short.

I repeated that mantra to myself many afternoons when my boys were small. Now they’re both at school it seems even more poignant. Because the years were short. They flew by. It just didn’t seem like it at the time, especially when I’d had given anything for adult company. Often the feelings of isolation and loneliness would leave me in a weeping heap (I’m sure many parents at home with small children can relate, or remember!).

Two particular things saved me from true loneliness when my boys were tiny — my mother’s group and a local playgroup. Going along to those groups every single week gave me something to look forward to. But more importantly, they gave me a sense of community, belonging, and connectedness. Some of the women I met became very dear friends, and the shared experience of motherhood turned out to be one of the greatest blessings that come along with having kids.

My life experiences have taught me that friendships are a very good thing for my wellbeing. And it turns out science has some very compelling evidence for the power of friendship too.

A 2010 meta-analysis of 148 studies including 300,000 people who were tracked for 7 1/2 years after completing surveys of their social connectedness found that,

Having friends and social connections means you’ll live longer.

The converse is also true. Social isolation is very bad for your health. The influence of social relationships on the risk of death are comparable with well-established risk factors for mortality such as smoking and alcohol consumption and exceed the influence of other risk factors such as physical inactivity and obesity.

Did you read that?!

The impact of socialising on survival is comparable with quitting smoking!

The negative impacts of social isolation were found to be:

  • Equivalent to smoking 15 cigarettes a day
  • Equivalent to being an alcoholic
  • More harmful than not exercising
  • Twice as harmful as obesity.

Contrast the impact of social isolation to the health of people with stronger social connections. They exhibited:

  • Lower rates of heart disease
  • Less infectious illness because of a stronger immune system
  • Lower blood pressure
  • Less abnormal inflammatory responses to stress
  • Lower rates of dementia.

In this study, measures of ‘social connection’ included whether someone was married or not, lived with other people, had less than monthly contact (including face-to-face, telephone, or written/e-mail contact) with their children or other family members or friends, and if they participated in social clubs or residents’ groups, religious groups, or committees.

The authors of the meta-analysis said,

Humans are naturally social. Yet, the modern way of life in industrialised countries is greatly reducing the quantity and quality of social relationships. Many people in these countries no longer live in extended families or even near each other. Instead, they often live on the other side of the country or even across the world from their relatives. Many also delay getting married and having children. Likewise, more and more people of all ages in developed countries are living alone, and loneliness is becoming increasingly common.

I don’t know about you but this finding makes me feel a bit sad.

Being socially connected maintains brain health.

Neuroscience research has shown that:

  • People who participate in high numbers of different leisure activities have a lower risk of developing dementia (activities include going to clubs, visiting friends or being visited, playing cards and community or volunteer work).
  • People with large social networks have a lower risk of dementia.
  • Loneliness is associated with more than double the risk of developing late-life dementia.

How do friends impact your brain health?

There are a number of theories:

  • Being socially connected to other people may reduce the harmful effects of stress (and I’ve written about the negative effects of stress on the brain in another blog post).
  • Friends may encourage healthy behaviours such as eating properly, taking medications, and practicing hygiene (no one wants a stinky mate!).
  • Interacting with other people may contribute to ‘cognitive reserve’. Cognitive reserve is a bit of a vague term, but it means how resistant the mind is to damage or deterioration of the brain. Socialising involves many cognitive functions such as thinking, feeling, sensing, reasoning and intuition. Mentally stimulating activities build up a reserve of healthy brain cells and promote the formation of new synapses (connections between brain cells) which may protect against dementia.

Your prescription for brain wellbeing: socialising!

I know from experience it takes courage to get out there, put on a smile and brave rejection when you are feeling alone and isolated. But keep in mind the benefits to your mental and physical wellbeing are as good for you as giving up smoking!!

I’m involved in two great initiatives that include connecting socially for brain health:

  • Join (or start up) a Walking Book Club. This combines social activity, with exercise and cognitive challenge as you walk and talk about the book with your friends. If you haven’t checked out the benefits to your brain health you can read about The Walking Book Club here.
  • Organise a Neural Knitworks event. These events combine social activity with mindfulness, and cognitive challenge as you craft/knit/weave woolly neurons and natter about neuroscience. Check out Neural Knitworks here.

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  1. Justi on June 7, 2013 at 4:41 pm

    Well I couldn’t sleep after our Tuesday night meeting 🙂 it was a great healthy brain social event 🙂

  2. Hasse Karlgreen on April 8, 2016 at 11:16 pm

    Hey, nice blog. I would like to share a story with you. One of my friends has been doing smoke and now he is facing a very big trouble. Now I have decided to help my friend to get rid of smoking habit. I know he will definitely stop this bad habit.

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About Dr Sarah

I’m an Oxford University-educated neuroscientist, presenter of ABC Catalyst, director of The Neuroscience Academy, and author of The Women's Brain Book. The neuroscience of health, hormones and happiness.

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