How your friends reduce your risk of dementia.

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“The days are long, but the years are short.”

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

Two things saved me from true loneliness when my boys were tiny: my mother’s group and a local playgroup. Going to those groups every 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 a true blessing that comes along with having kids.

It turns out science has some very compelling evidence for the power of friendship too.

A 2010 meta-analysis of 148 studies that tracked 300,000 people 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 terrible for your health.

The influence of social relationships on the risk of death is comparable with well-established risk factors for mortality, such as smoking and alcohol consumption. It exceeds the influence of other risk factors, such as physical inactivity and obesity. 🌱

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

The negative impacts of social isolation were found to be equivalent to,

  • smoking 15 cigarettes a day
  • being an alcoholic
  • or worse than not exercising
  • or more harmful than obesity.

In contrast, people with well-established supportive social networks show,

  • 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’ or ‘supportive networks’ included,

  • marriage or partnership  status
  • household status (single or two more housemates or family members)
  • contact less than once a month (including face-to-face, telephone, or written/e-mail contact) with their children or other family members or friends,
  • social club, resident groups, religious groups or committee participation.

The authors of the 2010 meta-analysis said,

“Humans are naturally social. Yet, the modern way of life in industrialised countries greatly reduces the quantity and quality of social relationships. Many people in these countries no longer live in extended families or 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.”

Holt-Lunstad, Smith, Layton 2010

I don’t know about you, but this finding makes me sad.

Being socially connected maintains brain health. 🌱

Research has shown that,

  • People who participate in many different leisure activities have a lower risk of developing dementia (activities include going to clubs, visiting friends or being visited, playing cards and doing 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 or socialising impact the brain on improving health?

There are a few theories:

  • Being socially connected to other people may reduce the harmful effects of stress.
  • Friends may encourage healthy behaviours such as eating properly, taking medications, and practising hygiene.
  • 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 brain damage or deterioration. 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 well-being: socialising! 🌱

I know from experience it takes courage to get out there, put on a smile and brave rejection when you feel alone and isolated. But remember that the benefits to your mental and physical well-being are as good for you as giving up smoking!!

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

  • Join (or start-up) a Walking Book Club. A walking book club combines social activity with exercise and cognitive challenge as you walk and talk about the book with your friends!
  • 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.

2023 Research Updates

🌟 Important New Research 🌟

The most extensive longitudinal study to date investigating the influence of loneliness on dementia risk was published in 2022 and encompassed over 460,000 participants from the UK BioBank. The study discovered a 26% increased dementia risk associated with social isolation.

This outcome was present despite the researchers statistically controlling for the influence of other known risk factors, such as physical inactivity, poor heart health, depression, level of education and genetic vulnerability.

True feelings of loneliness were also associated with increased dementia risk. However, that relationship was no longer significant once the researchers controlled for depression, with 75% of the association attributable to depressive symptoms.

This finding suggests there is a subtle difference between being socially isolated and feeling lonely. This is a small but important point: Being “alone” is a physical state where you are physically alone. Being “lonely” is an emotional state where you feel alone or disconnected from others.

Brain imaging studies have now shown that loneliness can affect the structure and function of key brain regions involved in executive functioning, emotional regulation, memory, self-awareness, motivation, and social perception. This means that your degree of social connectedness can fundamentally change your neural wiring and alter how your brain functions.

🌱 New Research 🌱

  • Feelings of loneliness increase overall mortality risk by 22%, with men experiencing a greater risk than women. However, the relative contribution of societal and biological factors to the increased mortality risk for lonely men is still yet to be determined.
  • The effect of loneliness on our health and well-being became especially evident during the COVID-19 pandemic. The social isolation associated with quarantine has been linked mainly to increases in anxiety disorders and other physical and mental health conditions.
  • Researchers have now shown that people with stronger social connections have a decreased risk of stroke, similar to their lower rates of heart disease.
  • People who report being lonely show increased biological hallmarks of Alzheimer’s disease compared to people who aren’t lonely. These brain changes include a more significant accumulation of toxic proteins, altered gene expression and lesions in their white matter.
  • Feeling socially connected also plays a critical role in protecting against mental health disorders. One recent review found that loneliness has a greater impact on mental health and well-being than any other health outcome. Strong social connections and frequent interactions with others are protective against depression and anxiety.
  • This prescribed socialising doesn’t always have to be in person, either! New research has shown that older adults who regularly use technology for social interactions have a 31% lower chance of being classified as socially isolated over four years!

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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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