We all wish to maintain our brain health throughout our lives, but sadly cognitive decline is all too common.

Decline in brain function can include forgetfulness, poor concentration and difficulty making decisions, which can all lead to dementia. The most common types of dementia are Alzheimer’s Disease and vascular dementia.

The Lancet Commission on dementia brought together leaders in the field to consolidate knowledge and make recommendations for prevention and management of the condition ⁽¹. It called dementia “the greatest global challenge for health and social care in the 21st century”.

Currently, more than 55 million people live with dementia worldwide and there are nearly 10 million new cases every year ⁽². In 2019, the estimated total global societal cost of dementia was US$ 1.3 trillion, and these costs are expected to surpass US$ 2.8 trillion by 2030 as both the number of people living with dementia and care costs increase. Nearly 85% of costs are related to family and social care rather than medical treatment.

Despite these depressing statistics, the good news is that up to 40% of cases could be prevented or delayed by adopting healthy lifestyle habits, in addition to addressing socio-economic determinants of health ⁽³.

Preventing dementia by addressing chronic health conditions

The development of dementia is driven by the same mechanisms as other chronic conditions, namely inflammation, dyslipidaemia, oxidative stress, insulin resistance and an unhealthy gut microbiome. Healthy lifestyle habits are therefore able to address these root causes and thus help prevent or delay the condition ⁽⁴.

Dementia shares similar risk factors to cardiovascular disease, that is heart attacks and strokes. Those who suffer with high blood pressure, cholesterol, type 2 diabetes and obesity are at significantly increased risk of developing dementia. In fact, dementia has been termed ‘type 3 diabetes’ because of the association with insulin resistance.

Addressing cardiovascular risk factors through a healthy lifestyle is an effective way to prevent dementia and boost brain health. An analysis from the Whitehall study of UK British civil servants included data from 7,899 participants, and reported the association of cardiovascular health at age 50 with the incidence of dementia, using the Life Simple 7 cardiovascular health score devised by the American Heart Association ⁽⁵⁾.

After a median follow-up of 25 years, the results demonstrated that the better the cardiovascular health score at age 50 years, the lower the risk of dementia. For each one-point increment in the score (14 points in total) there was a 11% reduction in the risk of dementia, demonstrating that control of cardiovascular risk factors provides a powerful tool for preventing dementia.

Further analysis from the Whitehall study cohort assessed the association between underlying chronic conditions, termed multi-morbidity, and the risk of dementia after 32 years of follow up ⁽⁶. The presence of two or more chronic conditions was associated with a 2.4-fold increase in risk of dementia. The younger the onset of the chronic conditions the higher the risk of dementia, with the strongest association at age 55 years.

The most common chronic conditions impacting risk were hypertension, depression, coronary heart disease and diabetes. Unsurprisingly, people with two or more of these chronic conditions also had a higher risk of death during the follow-up period, up to 4.8 times the risk of those without chronic conditions.

Healthy lifestyle - couple exercising

Keep physically active

Both aerobic and strength exercises benefit brain health and dementia risk by supporting metabolic and vascular health, while also reducing the risk of anxiety and depression.

General guidance on physical activity includes 150 minutes per week of moderately intense activity such as brisk walking, jogging, biking, swimming, dancing, and also strength building activities at least twice a week.

A meta-analysis of 15 prospective studies, including 33,816 participants, showed that a greater level of physical activity was associated with a 38% reduction in the risk of cognitive decline, with even low to moderate activity showing a benefit ⁽⁷ .

Sedentary behaviour has been associated with lower cognitive function, suggesting the more movement that can be incorporated the better ⁽⁸.

Resistance training over a six-month period in participants with mild cognitive impairment demonstrated improvement back to normal levels in 47% of individuals, with a greater impact of improving lower body strength and benefits maintained for 18 months ⁽⁹.

Healthy lifestyle - person going to sleep

The importance of sleep

Restorative sleep of seven to nine hours a night is essential for maintaining brain health and function, allowing the brain to detoxify, organise thoughts and lay down memories.

Some of our understanding comes from studying the health of shift workers, which shows that long-term shift work adversely affects cognitive function ⁽¹⁰. Various disorders of sleep, such as sleep apnoea, are associated with an increased risk of dementia and there is a bidirectional relationship such that individuals with dementia can develop sleep disorders ⁽¹¹.

Industrialised, western societies do not prioritise sleep enough due to an increasing 24-7 culture. Yet the consequences may well be serious later in life.

To help ensure good quality sleep, the following can help:

  • Maintain a regular sleep schedule
  • Avoid daytime naps — if you do, keep them to less than 30 minutes
  • Keep your bedroom at a cool temperature, around 15–19ºC
  • Ensure the room is dark and quiet
  • Avoid bright lights in the evening and sunlight in the morning
  • Avoid heavy, carbohydrate-loaded meals a few hours before bedtime
  • Minimise screen-time on electronic devices in the evenings and avoid after 9pm
  • Avoid caffeinated drinks and alcohol after 3pm.

Managing stress

Chronic psychological stress is associated with decline in cognitive function and a small brain, with prolonged elevations in the stress hormone cortisol associated with impaired learning and memory ⁽¹².

Addressing stress through interventions such as mindful meditation not only results in clinical improvement, but brain imaging studies show changes in brain connectivity ⁽¹³. Maintaining stimulating cognitive activity through life, including older age, supports better brain health and lowers the risk of dementia ⁽¹⁴.

Lifestyle medicine interventions

Combining healthy lifestyle habits is an effective way to protect brain health and prevent dementia. This was demonstrated in the Finnish Geriatric Intervention Study to Prevent Cognitive Impairment and Disability (FINGER), which examined the effects of a two-year comprehensive lifestyle intervention in 1,269 adults (60-77 years old) at risk of developing dementia.

One group received the following intervention: a diet intervention based on the Finnish Nutrition Recommendations (emphasises whole plant foods and minimises animal-derived and processed foods), regular aerobic exercise and resistance training, cognitively challenging computer programmes, and intensive management of metabolic and vascular risk factors. The second group received standard care (simply advice to eat healthily and exercise).

After two years, the intervention group had a significantly higher score in overall cognitive performance.

Healthy lifestyle - person refusing alcohol

Avoiding exposure to toxins

We are all aware of the health dangers of smoking, including an increased risk of dementia. While alcohol is a toxin and a carcinogen, we seem to be more lenient in our messaging about the risks, especially in cultures where drinking alcohol is a social activity.

Heavy consumption of alcohol is certainly detrimental to brain health, whereas low or moderate consumption may not cause harm, but does not provide any particular benefits either ⁽¹⁵/¹⁶. Any perceived benefits of alcohol, mainly wine, are from the polyphenols from the grapes, and are best consumed from natural food sources.

Exposure to environment toxics may also play a role in the risk of dementia. The most well-known is exposure to aluminium from water or through cookware ⁽¹⁷/¹⁸. Minimising exposure is recommended.

Conclusions

We have enough evidence to support the important role of a healthy plant-based diet alongside other health lifestyle habits for promoting brain health and preventing dementia. Lifestyle interventions not only reduce the risk of common chronic health conditions known to increase the risk of dementia, but also address the underlying pathogenic mechanisms at play in the development of dementia.

Here are my top seven tips:

  1. Focus your diet on healthy plant foods and try and incorporate as many different plants in your diet every week as you can
  2. Limit or avoid alcohol
  3. Prioritise sleep, aiming to get seven to nine hours every night
  4. Keep active during the day and break up long periods of sitting
  5. Build in a regular exercise
  6. Surround yourself with people who have a positive impact on your health and wellbeing
  7. Find an activity which brings you peace (e.g. meditation, writing, dancing, listening to music), anything that allows you to relax.

About the author

Dr Laura Freeman is a GP and lifestyle medicine physician. She is co-founder of Plant Based Health Online, an online lifestyle medicine healthcare service that supports patients to adopt healthy lifestyle habits for prevention and treatment of chronic illness.

You can find out more about Plant Based Health Online here.

Written By
Dr Laura Freeman, March 2022

References

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